,transcriber's ,notes ,italics1 bold face and small capitals in the source document have been transcribed between underscores1 between equal signs and as ,,all ,,capitals1 respectively4 ,more ,transcriber's ,notes and an overview of changes made may be found at the end of this text4 ,illustration3 ,frontispiece ,welding ,school1 ,ordnance ,department1 ,united ,states ,army1 ,peoria1 ,ill4 ,,wiley ,,engineering ,,series ,,oxy-,,acetylene ,,welding ,,manual ,,by ,,lieut4 ,,lorn ,,campbell1 ,,jr41 ,u4,s4,a4 ,officer in ,charge of ,welding ,instruction1 ,ordnance ,department1 ,u4 ,s4 ,army4 ,,total ,,issue1 ,,five ,,thousand ,,new ,,york ,,john ,,wiley ,,sons1 ,inc4 ,,london3 ,,chapman ,,hall1 ,,limited #aiai ,copyright1 #aiai ,,by ,,lorn ,,campbell ,copyrighted in ,great ,britain ,,press ,,of ,,braunworth ,,co4 ,,book ,,manufacturers ,,brooklyn1 ,n4 ,y4 ,,preface 7#a7 ,the oxy-acetylene method of welding and cutting metals has of late been receiving considerable attention4 ,its tremendous power of creating1 repairing and destroying the work of man has been but recently recognized in its broadest sense1 and the demand for operators1 skilled in the manipulation of this apparatus1 which always has been far in excess of the supply1 now knows no limit4 ,many authorities have set forth their views and theories upon this subject1 in ,america and also in foreign countries4 ,these have been published from time to time in many of the leading periodicals and magazines1 as well as in book form4 ,it seems the purpose of most of these works has been to advance the operators who already have a smattering knowledge of this art1 or to present to the purchaser of apparatus a set of operating instructions4 7#b7 ,it is singular indeed that a school manual1 devoted exclusively to the instruction of the beginner1 which will serve as an aid to the instructor as well as to the student1 has not yet been put forth4 ,it cannot be said that there is not a demand for such4 ,recently there seems to have been a mushroom growth of welding classes4 ,the majority of the vocational schools1 colleges1 night schools1 and automobile schools have all entered the instruction in oxy-acetylene welding on their rolls and each is attempting to instruct in an entirely different manner from the other4 ,there can be no question as to the expediency of affording the educational institutions a systematic as well as a standardized method of instructing4 ,but the books and articles of the nature mentioned are not suited to this purpose1 and were not designed for it4 ,a school-book is wanted2 something to be used in the classroom1 to be employed as a reference in the shop practice1 to be studied for what it contains1 and to indicate further lines of research1 where such are required4 7#c7 ,to meet this demand1 the present 8,manual0 has been written to serve the instructor as well as the student4 ,in its preparation many books1 both well-known and obscure1 have been examined and the methods of shop instruction have been carefully studied by the author4 7#d7 ,it has been found that regardless of how fast the ground may be covered in the lecture room1 the average student's power of assimilation is limited and considerable time has been spent in determining this ratio and applying it between the lecture subjects and shop work4 7#e7 ,it must be remembered that while the chapters comprising the theoretical part of this welding manual follow in the order given1 the actual shop practice1 as previously mentioned1 is the most important4 7#f7 ,kindly aid has been received from many sources4 ,granjon ,rosemberg1 ,kautney1 ,m4 ,keith ,dunham1 ,s4 ,w4 ,miller1 ,henry ,cave1 ,c4 ,j4 ,nyquist1 ,p4 ,f4 ,willis1 ,ben ,k4 ,smith1 and others have embodied in their writings many excellent ideas1 which have assisted the author in bringing out certain points advantageously4 ,the following manufacturers are to be given credit for many of the illustrations3 ,the ,oxweld ,acetylene ,co41 ,newark1 ,n4 ,j4 ,the ,united ,states ,welding ,co41 ,minneapolis1 ,minn4 ,the ,bastian ,blessing ,co41 ,chicago1 ,ill4 ,the ,linde ,air ,products ,co41 ,new ,york ,city4 ,the ,general ,welding ,equipment ,co41 ,boston1 ,mass4 ,the ,messer ,manufacturing ,co41 ,philadelphia1 ,pa4 ,the ,alexander ,milburn ,co41 ,baltimore1 ,maryland4 ,the ,torchweld ,equipment ,co41 ,chicago1 ,ill4 ,the ,davis-,bournonville ,co41 ,jersey ,city1 ,n4 ,j4 ,the ,k4 ,g4 ,welding ,co41 ,new ,york ,city4 ,the ,chicago ,eye ,shield ,co41 ,chicago1 ,ill4 ,the ,commercial ,acetylene ,supply ,co41 ,new ,york ,city4 ,the ,welding ,engineer1 ,chicago1 ,ill4 ,the ,journal of ,acetylene ,welding1 ,chicago1 ,ill4 ,,note4--,lieut4 ,campbell offers his services without charge to anyone interested in this method of welding and may be addressed care of ,,john ,,wiley ,,sons1 ,,inc41 ,publishers1 #dcb ,fourth ,avenue1 ,new ,york ,city4 ,,wiley ,,engineering ,,series ,the ,wiley ,engineering ,series will embrace books devoted to single subjects4 ,the object of the ,series is to place in the hands of the reader all the essential information regarding the particular subject in which he may be interested4 ,extraneous topics are excluded1 and the contents of each book are confined to the field indicated by its title4 ,it has been considered advisable to make these books manuals of practice1 rather than theoretical discussions of the subjects treated4 ,the theory is fully discussed in text-books1 hence the engineer who has previously mastered it there1 is1 as a rule1 more interested in the practice4 ,the ,wiley ,engineering ,series therefore will present the most approved practice1 with only such theoretical discussion as may be necessary to elucidate such practice4 ,,contents ,,page ,,introduction #a ,i4 ,,apparatus #ai ,,ii4 ,,operation #bg ,,iii4 ,,shop ,,equipment #ci ,,iv4 ,,apparatus ,,repairs #dd ,v4 ,,preheating ,,agencies #ea ,,vi4 ,,part ,,one--,,welding ,,of ,,cast ,,iron #eh ,,part ,,two--,,welding ,,of ,,cast ,,iron #fg ,,part ,,three--,,welding ,,of ,,cast ,,iron #gj ,,part ,,four--,,welding ,,of ,,cast ,,iron #ge ,,vii4 ,,part ,,one--,,steel ,,welding #ha ,,part ,,two--,,steel ,,welding #hg ,,part ,,three--,,steel ,,welding #ib ,,part ,,four--,,steel ,,welding #ig ,,viii4 ,,brass ,,welding #ajf ,,ix4 ,,part ,,one--,,aluminum ,,welding #aji ,,part ,,two--,,aluminum ,,welding #aac ,,part ,,three--,,aluminum ,,welding #aah ,x4 ,,welding ,,of ,,malleable ,,iron #abj ,,xi4 ,,oxy-,,acetylene ,,cutting #abe ,,xii4 ,,carbon ,,burning #ace ,,glossary #ade ,,lectures #adi ,,index #afg ,oxy-,acetylene ,welding ,manual ,,introduction 7#a7 ,when choosing a life vocation1 one generally views the possibilities it has to offer and delves deeply into these1 previous to making a decision4 ,it is therefore thought advisable at this time to present the student with an idea of what is meant by oxy-acetylene welding and cutting2 how it is applied2 the possibilities and advantages attached to such an art4 7#b7 ,acetylene gas1 when burned with a proper portion of oxygen gas1 produces an extremely hot flame1 in fact1 the hottest flame known4 ,its temperature is over #fjjj degrees ,fahrenheit4 ,with this flame it is possible to bring any of the so-called commercial metals1 namely3 cast iron1 steel1 copper1 and aluminum1 to a molten state and cause a fusion of two pieces of like metals in such a manner that the point of fusion will very closely approach the strength of the metal fused4 ,if more metal of like nature is added1 the union is made even stronger than the original4 ,this method is called oxy-acetylene welding and differs from what the average layman considers welding in the blacksmith's forge1 insomuch that there is no blow struck to assist fusion in this process4 ,and while the forge method is limited to wrought iron and steel which is detachable and of restricted size and shape1 the oxy-acetylene process has1 practically speaking1 no such limitations4 ,illustration3 7,courtesy of ,acetylene ,journal ,publishing ,co47 ,,fig4 #a4--,welders on an ,ordnance ,mobile ,repair ,unit in ,action4 ,illustration3 7,courtesy of the ,oxweld ,acetylene ,co47 ,,fig4 #b4--;,in ,enameled ,products for the ,kitchen the ,weld is ,fast ,replacing the ,riveting1 ,brazing1 and ,soldering of the ,light ,sheet ,metal ,seams4 7#c7 ,manufacturers in the metal-working world were very slow to grasp the real significance of this important process1 until the operators began demonstrating some of its possibilities4 ,at the present time1 however1 there is hardly a metal barrel or tank manufacturer who has not discarded the old method of producing costly leaky1 riveted drums and containers1 for this modern fusing process4 ,the manufacturers of fire-proof doors and windows1 cooking utensils1 seamless pipe and tubing1 office furniture and what not1 are now virtually dependent upon the welding torch at every turn4 7#d7 ,as a repairing agent1 the welding torch has no rival4 ,whether it is a casting of iron1 steel1 brass1 or aluminum that has broken2 a boiler or tank that has worn away in spots1 or an error on the part of engineer1 foundryman or machinist1 the part can generally be reclaimed and made stronger than originally4 ,to-day practically no manufacturing concern that is dependent upon metallic machinery could think of being deprived of its oxy-acetylene apparatus1 once having learned its worth4 ,in the not far distant past1 were a gear or some casting to break1 it probably meant closing down the entire plant until a new part could be obtained1 which1 whether the source of supply were near or at a long distance1 would mean costly delay4 ,with oxy-acetylene equipment and an efficient operator on hand1 almost every emergency is provided for4 ,illustration3 7,courtesy of the ,oxweld ,acetylene ,co47 ,,fig4 #c4--,welding ,broken ,frame of #e-ton ,automobile ,truck4 7#e7 ,if an automobile owner breaks a frame1 he does not consider replacing it with a new one1 as the labor alone for stripping his machine and setting it up again1 not to mention the cost of the new frame and the time required for this operation1 is prohibitive4 ,rather1 he has his car taken to the nearest welder or his portable apparatus to the car and the job is completed within thirty or forty minutes1 with the frame at the point of the break made stronger than ever4 ,locomotive frames are handled in much the same manner1 only more time is required and perhaps extra operators1 but the important point to be brought out is the fact that on many jobs no dismantling is required and the repair is permanently and quickly executed4 ,illustration3 ,,fig4 #d4--,staff of ,instructors at the ,ordnance ,welding ,school1 ,u4 ,s4 ,a4 7#f7 ,an interesting example of the true worth of welding was brought to the attention of the public when the ,united ,states entered the ,european ,war1 and all the interned ,german vessels1 which had been greatly damaged by the orders of their commanding officers1 were restored to working condition with the oxy-acetylene and electric welding process4 ,this was considered impossible by many engineers not familiar with the process1 insomuch as they looked upon oxy-acetylene welding as applicable only to small parts and here some of the sections which had been blown or struck out of the cast cylinders1 etc41 weighed many hundreds of pounds4 ,in many instances the ribs of these same vessels were cut most of their depth1 but these were restored to working order in a remarkably short time and the results were more convincing than any words4 7#g7 ,cutting with the oxy-acetylene process is just the opposite from that of welding4 ,the latter might be considered constructive and the former destructive4 ,in the case of welding1 two parts are brought to a molten condition along the line to be joined and both fused together4 ,whereas in cutting1 one piece of metal1 when brought to a red heat1 is cut in two by an oxidizing flame4 ,cutting has not the wide scope that welding has1 for it can only be applied successfully at the present day to wrought iron1 rolled and cast steel4 ,while it is limited in its scope1 the speed of this process in severing large masses of metal is very spectacular and appeals forcibly to the observer4 7#h7 ,probably the world's first awakening to the real meaning of oxy-acetylene cutting came when the ,u4 ,s4 battleship 8,maine10 was being taken from ,havana ,harbor4 ,all the heavy armor plate and seemingly immovable wreckage was cut into small sections which could be handled easily4 ,this was all accomplished with the cutting torch1 which seems to eat its way through metal with the same ease that a hot knife goes through butter4 ,illustration3 7,courtesy of the ,oxweld ,acetylene ,co47 ,,fig4 #e4--;,fireman ,cutting -inch ,steel ,fire ,door with ,portable ,apparatus4 7#i7 ,before and since the time of the 8,maine10 the cutting torch has been accomplishing wonderful feats4 ,in every scrap yard1 old boilers and the like are being cut into furnace size2 speeding up the production in answer to the world's cry for more metal4 ,the wreckage on railroads and buildings using steel reinforcements is being cleared in hours1 with the aid of the cutting torch1 where it required days by other methods4 ,most of the fire departments in the larger cities now carry the cutting torch as part of their equipment1 and to it has been credited the saving of many lives1 by its timely cutting away of steel doors1 bars or barriers which prevented escape4 ,much of the plate in this country's shipbuilding yards is being cut to size right on the job1 and the function of this torch in cutting off risers measuring from one to thirty-six inches in diameter in the foundry seems only to be of secondary importance in comparison with some of its other uses4 ,in order to transport some of the largest inland lake boats which were much too long to pass through the locks1 to the sea1 they were cut in parts1 transported1 and later welded together and placed in service4 ,illustration3 7,courtesy of the ,acetylene ,journal ,publishing ,co47 ,,fig4 #f4--,welders of the ,signal ,corps1 ,u4 ,s4 ,army1 in ,action4 7#aj7 ,it is not only possible to keep a cutting torch burning under water1 but it can also be made to cut4 ,contracting companies are cutting off their piling under water and it has been known that in ,european ports cutting has been successfully accomplished at a depth of thirty feet4 ,a special torch is employed by submarines to cut nets under water4 7#aa7 ,in reviewing the oxy-acetylene welding and cutting process1 we find that its growth is one of the most remarkable the world has ever witnessed4 ,about #aijg saw its industrial birth and since that time it has advanced by leaps and bounds1 rivaling the automobile industry in its progress1 despite the opposition and criticism levied at it by workers of other trades and its careless and unskilled manipulation4 ,illustration3 7,courtesy of the ,acetylene ,journal ,publishing ,co47 ,,fig4 #f;a4--,welders of the ,signal ,corps1 ,u4 ,s4 ,army1 in ,action4 7#ab7 ,it is quite impossible to present anything like a complete list of the applications of this process1 but a few of its general uses are here enumerated3 7,a7 ,airplane ,construction4--,welding of frames1 sockets1 water and gasoline tanks1 water jackets and valve cages to cylinders1 intake and exhaust manifolds and connections1 spark plug thimbles and the repair of aluminum crank cases1 etc4 ,illustration3 7,courtesy of the ,oxweld ,acetylene ,co47 ,,fig4 #g4--,welding a #b-;foot ,length of ,new ,shafting on the ,end of a ,motor ,shaft #b ,inches in ,diameter4 7,b7 ,automobile ,manufacture4--,welding of steel and aluminum bodies1 transmission and rear axle housings1 crank-shafts1 cylinders1 gears1 manifolds1 pinions1 crank cases1 valves1 rims1 mufflers1 frames1 fenders1 wind-shield tubings1 and uprights1 etc4 7,c7 ,boiler ,shops4--,welding and building up worn spots around hand-hold plates1 repairing cracks and checked portions of fire boxes1 retipping flues1 connections1 etc4 7,d7 ,brass and ,copper4--,welding kettles1 vats1 tanks1 stills1 floats1 cooking utensils1 manifolds1 water jackets1 electrical and chemical wares1 etc4 7,e7 ,commercial ,welding4--,reclamation service on all kinds of metals1 quick and permanent repairs on all broken parts of machinery4 7,f7 ,electric ,railway4--,welding air receivers on air-brake systems1 building up shafts1 bonding the rails1 motor housings1 worn boxes1 reclaiming gears and broken trucks1 steel trolley wires1 etc4 ,illustration3 7,courtesy of the ,torchweld ,equipment ,co47 ,,fig4 #h4--,this is a ,steel ,tank1 ,made of -inch ,plate1 which ,measures #cj ,feet ,long and #h ,feet in ,diameter1 ,fused into ,one ,piece by the ,welding ,torch4 7,g7 ,forge ,shop4--,welding complicated parts which can not be conveniently handled in the forge4 7,h7 ,foundries4--,welding up blowholes1 porous spots1 and reclaiming castings in general4 ,the cutting off of risers1 gates1 and heads on steel castings4 7,i7 ,lead ,burning4--,lead pipe joints1 storage battery connections and repairs1 lead linings in vats1 etc4 ,illustration3 7,courtesy of ,ben ,k4 ,smith1 ,u4 ,s4 ,welding ,co47 ,,fig4 #i4--,locomotive ,cylinder to be ,welded in ,place4 7,j7 ,lumber ,mills4--,building up worn shafts1 repairing gears1 chains1 and broken parts4 7,k7 ,machine ,shops4--,rectifying errors on part of machinists and engineers4 ,a 8putting-on0 tool in every respect4 7,l7 ,manufacturers4--,welding spouts and handles on cooking utensils1 fire-proof doors and window sashes1 office files and furniture1 chains1 etc4 7,m7 ,mines4--,repairing pipe lines1 boilers1 broken shafts1 gears1 and building up worn parts on dippers1 etc4 ,the cutting torch is used for clearing away wreckage in case of accidents4 7,n7 ,pipe ,work4--,welding of water1 gas1 and oil1 steam and air lines4 ,high-pressure refrigeration systems are cut and welded in place4 ,illustration3 7,courtesy of the ,oxweld ,acetylene ,co47 ,,fig4 #aj4--,steel ,roll ,top ,desk--all ,joints and ,seams ,welded4 ,an ,excellent ,example of ,high-grade ,welded ,metal ,furniture4 7,o7 ,plate ,welding4--,tanks for oil1 steam driers1 digesters1 vats1 chemical receivers1 generators1 etc4 7,p7 ,power ,plants4--,welding of steam1 air1 and water-lines1 of pump castings1 cylinders1 pistons1 worn or broken parts1 etc4 7,q7 ,railroad ,work4--,reclaiming bolsters1 couplings1 slotting forged engine rods1 building metal cars1 repairing fire-boxes1 patching and replacing side sheets1 flue welding1 building up frogs and crossings1 cutting off rails1 mud rings1 welding cracked cylinders1 cross-heads1 steam-chests1 building up worn spots on wheels1 rims and pins1 welding spokes and locomotive frames1 etc4 ,illustration3 7,courtesy of the ,oxweld ,acetylene ,co47 ,,fig4 #aa4--,office ,chair4 ,welded at all ,joints4 7,r7 ,rolling ,mills4--,fabricating 8open-hearth10 water jacket doors1 cutting up 8lost heats10 scrap plates and bar stock billets4 ,general repairs of furnace equipment1 hot beds1 rolls1 gears1 engines1 plates1 etc4 7,s7 ,sheet ,metal4--,manufacture of tubing1 oil-storage barrels1 metallic furniture1 range boilers1 etc4 7,t7 ,shipyards4--,cutting off plates and irregular shapes of steel1 channels1 special sections4 ,building up of worn shocks1 building and patching hulls1 stringers and the reclamation of propellers1 posts and broken parts of machinery1 etc4 7,u7 ,structural ,steel4--,cutting holes for rivets1 gussets and splice plates1 and wrecking4 ,welding up misdrilled holes and machinist's errors4 ,cutting channels1 ,i beams1 and other shapes for coping1 splicing and fitting rails1 welding reinforcing rods for concrete work of any desired length and structural parts where bolting and riveting is difficult or impossible4 ,illustration3 7,courtesy of the ,british ,oxygen ,co47 ,,fig4 #ab4--;,cutting ,armor ,plate by the ,oxy-acetylene ,process4 7,v7 ,scrap ,yards4--,cutting up scrap boilers1 tanks and other large work to mill size1 wrecking structural buildings1 and reducing to small size1 reservoirs1 tanks and boilers1 which are housed in buildings to remove them without damage to the structures4 7,w7 ,tractor ,industry4--,cutting and welding frames1 track and wheel guards1 water1 gasoline1 and oil tanks2 welding up of blowholes1 porous spots and misdrilled holes in castings of all kinds4 ,illustration3 7,courtesy of the ,davis-,bournonville ,co47 ,,fig4 #ac4--;,here is ,illustrated an ,oxy-acetylene ,machine for ,cutting ,holes in the ,web of ,rails1 or in ,structural ,iron1 of not more than ,inch in ,thickness4 ,it can be ,quickly ,attached and ,accurately ,adjusted to ,pierce through the ,iron ,instantly1 without any ,previous ,drilling1 and it will ,cut ,smooth ,round ,holes1 from to #b ,inches in ,diameter in from #cj to #fj ,seconds4 ,it is ,particularly ,adapted for ,railroad ,work1 and ,enlarging or ,cutting ,holes in ,building and ,bridge ,work4 7#ac7 ,the foregoing1 as previously stated1 is but a partial list of some of the applications of the oxy-acetylene welding and cutting process to various industries4 ,what has the future in store for it8 ,almost daily1 some new application is found for it and at the present time experiments are under way in boiler construction1 the results of which are not difficult to foresee4 ,giant hulls of seagoing vessels are being fused together by welding and the limits of this wonderful process which is now practically in its infancy are difficult to forecast4 7#ad7 ,during the ,world ,war many manufacturers of non-essentials shut down and others turned their entire production over to the government1 changing their machinery and in most instances their entire plant4 ,what1 then1 are those who are operating machines and apparatus1 produced by these firms before the war1 going to do for replacements8 ,there is but one answer1 have their broken or worn out parts welded4 7#ae7 ,oxy-acetylene operators have always numbered far less than the demand1 a point which was clearly brought out by the government when its immense ,army and ,navy were being formed4 ,there were so few men familiar with the oxy-acetylene process that it at once took measures to establish its own schools where men could be trained1 a thing that the commercial world had been ,,thinking of doing for some years4 ,as the demand for operators continues to increase1 it behooves a man1 even though he is not a metal worker1 to think and apply himself1 in order that he may 8carry on10 to the best advantage when opportunity knocks4 7#af7 ,the methods of instruction herein set forth are very simple and while differing in many respects from those used by the trade1 have been most successfully employed in producing efficient operators4 ,certain principles are instilled in the beginner and some of the exceptions which are of minor importance are overlooked to avoid confusion4 ,criticism is expected from those who have never engaged in instruction of this kind on a large scale4 ,there are many differences to be expected on account of this very fact1 for there are few who have gone further than the instruction of very small classes where individual attention may be given4 7#ag7 ,all history of the process1 gas manufacture and the like have been omitted in order to give greater detail to the actual shop practice and to have the operator become familiar with his apparatus and thereby operate it with all due respect and intelligence4 7#ah7 ,oxy-acetylene welding cannot be learned by watching others work1 although observation may at times assist the beginner4 ,actual torch practice1 brain work and a power of 8,i will10 produce the most efficient operators4 ,for those who earnestly apply themselves to the instructions which follow1 there is every reason to believe that success will be theirs4 ,,chapter ,i ,,apparatus 7#ai7 ,welding apparatus in general consists of two regulators equipped with pressure gauges1 two lengths of hose1 and a welding torch4 ,the regulators are attached to cylinders of acetylene and oxygen and are used to reduce and maintain a uniform pressure of these gases for use at the torch4 ,the gases at reduced pressure are conveyed to the torch by the hoses4 ,the regulators should each have a high-pressure gauge to indicate the contents of the cylinder1 and also a line or working-pressure gauge to show the gas pressure on each hose4 ,when the gases reach the torch they are there mixed and combustion takes place at the welding tip1 which is fitted to the torch4 ,such an apparatus is called portable1 on account of its movability4 ,there are other equipments wherein one or both of the gases are generated1 but these will not be discussed here4 ,illustration3 ,,fig4 #ad4--;,a ,portable ,welding ,unit4 7#bj7 ,for convenience oxy-acetylene welding apparatus may be divided into three classes1 depending upon the principles used in securing the fuel gas or acetylene for the flame4 ,low-pressure1 medium-pressure and high-pressure apparatus generally use about the same pressure of oxygen and it will be called a constant4 ,the acetylene gas is a variable and in the low-pressure type only enough pressure is required to overcome the friction of the line until it reaches the oxygen injector1 located in the torch1 which acts as a syphon1 drawing the acetylene gas to the point of ignition4 ,in a medium-pressure type about three-fourths as much pressure is required on the acetylene line as on the oxygen4 ,this type is apt to verge on the injector type1 as it depends to some extent upon the oxygen under pressure carrying acetylene gas to the point of ignition4 ,in the high-pressure type equal pressure on each line is used4 ,to further make this classification clear1 a certain sized tip using1 perhaps1 #ab pounds of oxygen pressure can be used as an example4 ,in a low-pressure type perhaps #b pounds pressure or less will be needed on the acetylene line4 ,on the medium-pressure approximately #i pounds will be required1 while on the high-pressure an equal amount1 or #ab pounds will be needed4 ,illustration3 ,,fig4 #ae4--,location of ,mixing ,chambers in ,welding ,torches4 7#a7 ,shows gases mixing in the handle4 7#b7 ,has the mixing chamber in the middle of the torch4 7#c7 ,illustrates how the gases are kept separate until the head of the torch is reached4 ,ox4 represents oxygen gas2 ,ac4 acetylene gas2 and m mixing chamber4 7#ba7 ,the mixing chambers for the gases may be located in the head2 in the middle of the torch1 or in the handle4 ,by mixing chambers reference is made to that portion of the torch where the two gases are brought together and mixed4 ,as can be seen with three different types of welding torches and three different locations for the mixing of the gases1 the manufacturers can find a large range for producing oxy-acetylene apparatus4 ,some undoubtedly will fill certain requirements better than others4 ,much1 too1 will depend upon the ability of the operator in handling a torch4 7#bb7 ,flashbacks are caused by the improper mixture of the gases1 which increases the rate of flame propagation to such an extent that the flame will flash back to the mixing chamber4 ,acetylene in a pure state will burn very much slower than when mixed with equal parts of oxygen4 ,when more oxygen is introduced the flame propagation is much greater1 so that when an excess of oxygen is used1 there is bound to be considerable trouble from backflashing4 ,when sufficient acetylene is introduced to the mixing chamber1 there is absolutely no chance for this lean mixture to occur4 ,if the flame flashes back to the mixing chamber1 both gases should be closed off immediately1 at the torch1 the oxygen first1 and then the acetylene gas4 7#bc7 ,in some torches the heating of the mixing chamber will cause a flashback and with these it is necessary to shut off the acetylene and leave the oxygen valve just cracked and immerse the torch head in water1 dipping it slowly1 so as not to cause too great a strain4 ,the oxygen will bubble out and prevent the water backing up in the tip4 ,if the flashback deposits enough soot on the inside of the tip and the head to impair the working quality of the torch1 the soot should be removed by using a soft wire1 preferably of copper1 or some other material which will not mar the tip4 ,illustration3 ,,fig4 #af4--;,cross-section of ,regulator4 ,a1 chamber2 ,b1 nozzle2 ,c1 seat2 ,d1 seat arm2 ,e1 diaphragm2 ,f1 cross-bar1 or adjusting screw2 ,g1 diaphragm springs2 ,h1 gas outlet2 ,i1 gas inlet4 7#bd7 ,it is interesting to note the action of a regulator1 used to reduce the cylinder pressure on both gases4 ,the gas from the cylinder1 at high pressure1 comes directly into the body of the regulator or chamber 7,a71 ,fig4 #af1 through a fine nozzle 7,b74 ,a seat of gallilith1 casenite1 or fiber 7,c71 attached to an arm 7,d71 presses against this nozzle4 ,arm 7,d71 in turn1 is attached to a very sensitive diaphragm 7,e7 and is moved every time there is a pressure exerted on the latter4 ,the movement of this diaphragm is controlled by a handle or a screw1 with a 8cross-bar0 attached to its end as is shown at 7,f74 ,this screw bears upon the diaphragm through the medium of the springs 7,g74 ,as this screw is forced inward the springs force the diaphragm in1 and thereby move the seat away from the nozzle of the regulator4 ,the gas1 entering under high pressure1 exerts an equal force on all parts of the chamber and the diaphragm receives its share4 ,now the chamber walls are made of a solid material1 usually a bronze or brass1 and cannot be changed1 but this diaphragm can be moved and as this pressure is increased1 the diaphragm is forced out and the nozzle 7,b7 is automatically closed by having the seat 7,c7 brought in contact with it4 ,when gas is drawn off through the line 7,h71 the pressure within the chamber will naturally drop and as it does so1 the springs will force the diaphragm inward1 permitting a replacement of the gas drawn off4 ,although not noticeable1 there is a continual movement of this diaphragm whenever the gas is being used4 ,it can be readily seen that the amount of pressure within the regulator can be accurately set by the tension of the spring against the diaphragm which is controlled by the screw carrying the 8cross-bar40 7#be7 ,there are two types of regulators manufactured for the reduction of gases under high pressure1 depending upon the nature of work to be done4 ,the high-pressure regulator is employed for heavy work where a great deal of gas is used and the regulator must pass it without much effort1 to prevent its freezing4 ,this type of regulator is used on cutting or on large welding work4 ,it differs from the low-pressure or ordinary type in four distinct features4 ,generally it contains a much heavier diaphragm which is smaller in diameter1 making it stiffer in every respect4 ,the tension springs which act upon this diaphragm are much heavier4 ,the nozzle which presses against the seat is much larger1 to permit the passage of a greater amount of gas4 ,then1 too1 a larger working pressure gauge must be used1 in order to read this high pressure4 ,in the welding of metals1 especially in steel1 the adjustment of the flame is a very important matter1 and absolutely dependable regulation must be had4 ,this is not possible with a high-pressure regulator and is not intended to be so4 ,the larger the diaphragm1 the more sensitive the regulator1 and this point should be borne in mind1 and no small welding work attempted with the high-pressure regulator4 ,the reverse form of reasoning may be applied to low-pressure regulators which have been used in cutting4 ,they are very likely to be strained and satisfactory results cannot be expected1 for they are not made for that purpose4 ,acetylene regulators are constructed much more sensitively than the oxygen regulators1 to take care of the lower pressure of gas and in a sense might be called weaker1 insomuch that the larger nozzle which passes the gas is closed or regulated by springs which are not nearly as strong as in the oxygen regulator4 ,for this reason acetylene regulators cannot be interchanged with oxygen regulators for they will not stand the pressure demanded in the first place1 and in the second place1 were a small quantity of acetylene gas left in the regulator and oxygen introduced1 an inflammable mixture would be formed which is not advisable to have present1 on account of its explosiveness4 ,in many instances oxygen regulators are put out with the copper diaphragms1 whereas another metal must be used on the acetylene regulators1 because acetylene gas attacks copper and usually a ,german silver or rubber diaphragm is used4 ,on account of the lower pressures used in charging the acetylene cylinders1 lower pressure gauges are used than on oxygen regulators4 7#bf7 ,all tension should be removed from the diaphragm springs by screwing out on the 8cross-bar0 7that is1 to the left71 before admitting gas under pressure to the regulator to avoid abusing the seat4 ,if a matter of #ahjj pounds pressure were admitted suddenly into any regulator that had the seat removed from the nozzle1 there would be a sudden exertion upon the diaphragm1 which would draw the regulator seat up very violently against the nozzle1 and if it did not crack the seat it would undoubtedly groove it to such an extent that it would leak and a trouble known as 8creeping regulator0 would result4 ,if this occurs1 good work cannot be expected because the flame will not remain steady1 and it is therefore necessary to take steps to rectify this abuse4 ,if there is a welding company available1 the regulator should be sent to it for repairs1 but if the operator is in an isolated district when this occurs1 and must have some means of continuing work1 it will be possible for him to remove the seat by unscrewing the back of the regulator4 ,if the seat has become grooved1 and he thinks that this is the trouble1 many times the seat can be turned over and the machined surface on the other side used4 ,if the seat is cracked1 however1 about the quickest way of making an emergency repair is to turn out a new seat from hard rubber or fiber on a lathe4 7#bg7 ,in acetylene cylinders an absorbent called acetone is generally used1 which gives up the gas as required4 ,a full cylinder can be used for some time without any noticeable difference in the gauge reading1 and then1 as it nears the empty point1 the gauge reading will drop very perceptibly4 ,it is therefore impossible to depend upon a high-pressure acetylene gauge as an index to the contents of the cylinder4 ,the only method known to correctly check the amount of acetylene gas on hand is to weigh the cylinder4 ,there are #ad cubic feet of acetylene gas to the pound1 and when the net weight of the cylinder is given the contents can readily be figured4 ,a tag bearing the net weight or figures which will permit its computation is generally found attached to each acetylene cylinder4 ,in the case of oxygen cylinders1 there being no absorbent used1 the contents of the cylinder is indicated on the high-pressure gauge4 ,on the latest type gauge the contents will be shown by cubic feet1 by pounds pressure and by atmospheric pressure1 to facilitate the computation of costs by the operator4 7#bh7 ,occasionally a needle valve on a torch will begin to leak and it will be found necessary to grind it4 ,realizing that oil and grease are not to be used where oxygen is in evidence1 the question is often brought up as to the proper lubricant to be used in doing this kind of work4 ,glycerine is used by most manufacturers1 together with powdered glass or flour emery4 ,in doing work of this kind the finished job is thoroughly washed with ether4 ,occasionally when piping oxygen lines through the shop1 a screwed coupling will leak and there is a temptation to calk the same with white lead1 but this should never be done1 rather use lead oxide mixed with the glycerine for this purpose as it forms a paste which sets very rapidly and forms a hard1 tough compound4 ,,chapter ,,ii ,,operation 7#bi7 ,in oxy-acetylene welding there are two gases used1 as the name would indicate1 namely1 oxygen and acetylene4 ,the first is used to intensify the flame and can in nowise be likened to the inflammable nature of the second4 ,there is a great deal of oxygen present in the air we breathe4 ,it is an odorless1 tasteless1 and colorless gas1 as most of us are aware4 ,in the commercial world oxygen is manufactured by the decomposition of water into its elements1 oxygen and hydrogen1 by the electrolytic process or is taken from the air by a reduction process and is stored in steel-drawn cylinders4 ,these cylinders are drawn out of one piece of steel and are of considerable thickness throughout1 having absolutely no seams1 welded or otherwise4 ,there is no filler nor absorbent used on the inside of these cylinders1 as pure oxygen under pressure is not considered dangerous4 ,the standardized sized oxygen cylinder is one which contains #bjj cubic feet of gas fully charged4 ,oxygen is compressed in these cylinders at a pressure of #ahjj pounds1 at normal temperature1 and this pressure does not vary to any great extent with change in temperature 7as shown by table on page #bi74 ,there is attached to the tip of the steel cylinder1 or 8bottle10 as some workers call it1 a double seating valve which has one seat operate when the cylinder is closed1 and the other when the cylinder is wide open4 ,a regulator is attached to this valve when working4 ,illustration3 ,,fig4 #ag4--,sectional ,view of ,oxygen ,cylinder without ,valve4 ,illustration3 7,courtesy of the ,linde ,air ,products ,co47 ,,fig4 #ah4--;,a ,standard #bjj-;foot ,oxygen ,cylinder4 ,illustration3 ,,table ,,showing ,,the ,,different ,,pressures ,,of ,,oxygen--,,at ,,various ,,temperatures ---------------------------------------- -------- ,temp4 ,press4,temp4 ,press4,temp4 ,press4,temp4 ,press4 ,deg4,lb4 ,per ,deg4,lb4 ,per ,deg4,lb4 ,per ,deg4,lb4 ,per ,fahr4 ,deg4 ,fahr4 ,deg4 ,fahr4 ,deg4 ,fahr4 ,deg4 ---------------------------------------- -------- #j #aefh #be #afed #ej #agci #ge #ahbd #a #aegb #bf #afeg #ea #agdc #gf #ahbh #b #aege #bg #affj #eb #agdf #gg #ahca #c #aegi #bh #affd #ec #agdi #gh #ahce #d #aehb #bi #affg #ed #agec #gi #ahch #e #aehe #cj #afga #ee #agef #hj #ahdb #f #aehi #ca #afgd #ef #agfj #ha #ahde #g #aeib #cb #afgh #eg #agfc #hb #ahdh #h #aeif #cc #afha #eh #agff #hc #aheb #i #aeii #cd #afhd #ei #aggj #hd #ahee #aj #afjc #ce #afhh #fj #aggc #he #ahei #aa #afjf #cf #afia #fa #aggg #hf #ahfb #ab #afji #cg #afie #fb #aghj #hg #ahfe #ac #afac #ch #afih #fc #aghd #hh #ahfi #ad #afaf #ci #agja #fd #aghg #hi #ahgb #ae #afbj #dj #agje #fe #agij #ij #ahgf #af #afbc #da #agjh #ff #agid #ia #ahgi #ag #afbf #db #agab #fg #agig #ib #ahhc #ah #afcj #dc #agae #fh #ahjj #ic #ahhf #ai #afcc #dd #agai #fi #ahjc #id #ahhi #bj #afcg #de #agbb #gj #ahjg #ie #ahic #ba #afdj #df #agbe #ga #ahaa #if #ahie #bb #afdc #dg #agbi #gb #ahad #ig #aijj #bc #afdg #dh #agcb #gc #ahah #ih #aijc #bd #afej #di #agcf #gd #ahba #ii #aijf #ajj #aiaj ---------------------------------------- -------- ,,fig4 #ai4 7#cj7 ,acetylene is the fuel gas1 and is one of the greatest containers of heat known4 ,burning in a free state1 its carbon content is so rich that complete combustion is impossible1 and stringy black particles will be noticed floating through the air4 ,in order to fully combust this gas1 oxygen is introduced under pressure and a temperature of over #fjjj degrees ,fahrenheit is obtained4 7,acetylene contains about five times as many ,b4 ,t4 ,u4's 7,british ,thermal ,units7 as hydrogen47 ,this gas1 unlike oxygen1 becomes very dangerous when in a free state it is subjected to an excessive pressure4 ,the slightest jar may cause its disintegration and a violent explosion follows4 ,on account of this danger1 acetylene is not stored in a free state2 neither is it subjected to very high pressures4 ,its cylinders are put out by various manufacturers to comply with the laws and regulations of the ,interstate ,commerce ,commission4 ,some of these cylinders have been welded1 but the most modern method is to make them of one piece of drawn steel4 ,they are then filled with an absorbent of some kind to take up the gas and prevent any portion of it being left in a free state4 ,acetone is the popular absorbent1 and is a liquid capable of absorbing twenty-five times its own volume of acetylene gas at normal pressure4 ,the filling material varies with each of the manufacturers1 but charcoal1 asbestos and mineral wool are in very common use4 ,acetylene is obtained from calcium carbide brought in contact with water1 or vice versa1 and is compressed and then stored in the cylinders at a pressure varying from #aej to #bej pounds4 ,when fully charged this pressure will vary almost directly with any change of temperature4 ,acetylene cylinders for welding are available in #ajj1 #bjj1 #bbe1 and #cjj cubic foot sizes4 ,illustration3 ,,fig4 #bj4--;,a ,generator for ,producing ,acetylene under ,pressure4 7#ca7 ,in setting up apparatus for the first time1 the regulator containing the #cjjj-pound gauge is attached to the taller of the cylinders1 which holds the oxygen gas1 and the other regulator is fastened to the shorter cylinder4 ,the hoses1 which should be cleared of all powder or scale on their interior1 are then added4 ,the black hose should connect the oxygen regulator to the torch valve1 marked 8,,ox0 and the red hose1 the acetylene regulator to the torch valve stamped 8,,ac40 ,in attaching regulators to full cylinders the 8cross-bar0 on the regulator should always be turned out1 that is to the left1 until it turns freely1 to insure all pressure being released from the diaphragm1 before the cylinder pressure is turned on4 ,another precaution that should be observed is the 8cracking0 of the cylinder valves1 before attaching the regulator1 in order to blow out any dirt or foreign particles that may be lodged there1 otherwise they will be carried into the regulator seat1 or lodged in some small passage1 which will impair the working of the apparatus4 ,then too1 if no truck or clamping device has been provided1 both the oxygen and acetylene cylinders should be securely clamped or wired together1 a rule which should be insisted upon at all times1 whether in a job shop1 manufacturing concern1 or training school1 or any place where top-heavy oxygen cylinders are being used4 ,no particular harm results if these cylinders are turned over1 which is very easily done on account of their rounded base1 if no regulator is attached1 but very frequently regulators are attached and the hose connecting the same to torch is found in the operator's way4 ,the slightest pull or tripping on this hose will upset the cylinder1 usually demolishing the regulator and expensive gauges and at times causing much confusion among the workmen1 on account of the loud hissing noise given off by the escaping gas4 ,always secure the drums or the cylinders in a safe manner4 7#cb7 ,in turning on the gas1 the oxygen valve is opened wide until seated and the acetylene valve is only partially opened4 ,often the question is raised as to where the operator should stand1 especially when dealing with high-pressure oxygen4 ,it is recommended that the operator should stand at the side and towards the rear when performing this operation1 for sometimes an unreliable gauge may be attached1 which if bursting1 would send the glass into the operator's face4 ,illustration3 ,,fig4 #ba4--;,acetylene ,flame ,blowing away from ,tip4 ,illustration3 ,,fig4 #bb4--;,addition of ,oxygen to ,acetylene ,flame4 ,illustration3 ,,fig4 #bc4--,more ,oxygen ,pressure ,applied4 ,flame ,contains ,slight ,excess of ,acetylene1 and is ,known as 8,carbonizing40 ,illustration3 ,,fig4 #bd4--8,neutral0 ,flame4 ,correct ,proportions of ,oxygen and ,acetylene ,gases4 ,illustration3 ,,fig4 #be4--8,oxidizing0 ,flame4 ,too much ,oxygen ,present4 7#cc7 ,as soon as an operator has gas pressure in his regulators1 he begins wondering how much pressure should be placed on his line1 that is1 the portion between the regulator and the torch4 ,of course1 this depends upon the size of the tip1 but the operator should have some means of approximating this pressure without going to his manufacturer's chart every time4 ,a neutral flame1 that is1 theoretically equal parts of oxygen and acetylene1 is desired for welding4 ,now in lighting1 the flame should stand away from the tip a slight distance1 in torches other than the low-pressure type1 while in these there will only be a good full flame issue from the tip4 ,enough oxygen must be in evidence to bring this acetylene flame down to the neutral point4 ,if not enough pressure is used1 this result cannot be obtained1 and of course1 more pressure must be introduced4 ,it is better to have too much pressure than not enough on the line1 for the operator may use his torch valve to again regulate this pressure and is always sure of enough gas4 ,theoretically1 all adjustments should be made at the regulator1 but in practice this is very seldom carried out4 ,the accompanying cuts will illustrate the five conditions which every welder should be familiar with1 in the flame adjustment4 ,fig4 #ba shows the acetylene turned on full2 no oxygen has as yet been introduced4 ,the flame has a yellow appearance and is very rich in carbon1 as can be seen by the soot given off4 ,in ,fig4 #bb we see the oxygen being turned on2 the yellow flame 7,a7 is gradually giving way to a white part at 7,b74 ,in this condition we say that a feather flame exists4 ,fig4 #bc shows slightly more oxygen pressure4 ,in ,fig4 #bd we have the neutral flame1 which can be readily recognized on account of its bluish white color and well-defined outline1 appearing like the end of an unused piece of chalk1 only1 of course1 much smaller4 ,in ,fig4 #be can be seen an excess or too much pressure of oxygen4 ,it will be noticed that the neutral flame assumes a more bluish color1 is a little pointed1 and a very noticeable hissing sound is in evidence4 ,this is what is called an oxidizing flame and will be again referred to4 ,too much oxygen is used4 ,operators who attempt to turn on the oxygen first and then light it1 will find that it does not burn1 and their efforts will be useless4 ,in picking up a torch for the first time1 any operator can turn on one valve and detect by the odor of the gas1 whether it is oxygen or the fuel gas1 and can light it in accordance4 ,some operators1 however1 attempt to turn on a little of each gas and light4 ,this is not to be recommended1 for flashbacks may occur4 ,when the welder accustoms himself to turning on enough pressure to accommodate whatever sized tip he may have1 he will find that there is no great need for paying attention to the pressure gauges on his regulators except to check up on the full drums of oxygen1 and to tell whether he has enough gas left to complete a certain piece of work4 7#cd7 ,a neutral flame is theoretically composed of equal parts of oxygen and acetylene ignited1 but this ratio is very seldom worked out in practice4 ,there is usually an excess of oxygen in evidence4 ,a neutral flame is generally spoken of as being over #fjjj degrees ,fahrenheit1 and this does not vary with the different sized tips as most welders think4 ,of course there are different quantities of heat between a very small tip and a large sized one1 but the temperature of the flame is the same4 7#ce7 ,if too much acetylene gas is used1 a feather flame such as was seen in ,fig4 #bc will appear4 ,this has a carbonizing effect on the weld1 for it introduces carbon and causes the weld to become very brittle4 7#cf7 ,if too much oxygen gas is used1 the effect shown in ,fig4 #be will take place1 and the weld will have oxygen introduced1 which is a very detrimental feature1 and is particularly noticeable in working on steel1 for it raises a white foam over the surface of the melted metal1 which sometimes is worked right into the weld itself4 ,an experienced welder will always know just what kind of a flame action he is obtaining on his weld1 not because he takes the flame away every time he wishes to look at it1 but he can tell by the action of his metal exactly the nature of his flame4 7#cg7 ,infra-red 7heat7 and ultra-violet 7light7 rays present to a small extent in the neutral flame are injurious to the naked eye4 ,colored glasses or goggles are used to shield the eyes when working with this flame4 ,too dark a glass should not be used1 as it will cause a strain upon the eyes more injurious than the flame4 ,exposed metal frames should be avoided too1 as they hold the heat and burn the operator4 ,illustration3 7,courtesy of the ,chicago ,eye ,shield ,co47 ,,fig4 #bf4--;,a ,spectacle ,made for ,welders1 having a ,frame of ,fiber and ,arranged so that ,lenses may be ,replaced4 ,illustration3 7,courtesy of the ,chicago ,eye ,shield ,co47 ,,fig4 #bg4--,showing ,cover ,glass which ,protects the ,colored ,lens and the ,replaceable ,features of a ,modern ,goggle4 7#ch7 ,to shut off the apparatus for several hours or so1 it is best to relieve all pressure from the lines1 such as hose and so forth1 and to do this close both tank valves2 open the torch valves2 release the tension on the regulator1 by screwing the 8cross-bar0 to the left1 and finally1 close the torch valves4 ,it is quite necessary that these torch valves closed1 for quite frequently1 if a small tip is in the torch and an excess of oxygen pressure comes through the line1 when both torch valves are open1 much of the oxygen may back up the acetylene line and cause a serious flashback when lighting up4 ,this can be avoided by keeping both torch valves closed when not in use4 7#ci7 ,if a valve on an empty acetylene cylinder is left open the acetylene gas will escape1 and mixing with the air1 which is a supporter of combustion1 a very inflammable mixture will be formed4 ,if any fire is present1 such as might be smouldering in a forge1 possibly not used for several hours or so1 or a match lighted1 or a flame started in any way1 an explosion is likely to occur4 ,when an acetylene cylinder is exhausted1 as far as possible1 in a moderately high atmospheric temperature1 then shut off for a while and the temperature drops1 air will be drawn into the vacuum thus formed when the valve is again opened4 ,in this manner an explosive mixture forms in an empty acetylene cylinder and is certainly to be avoided4 ,care should be taken1 especially in winter1 to guard against such occurrences1 as in some outlying shops a decided change in temperature takes place between closing time and starting up time the following morning4 ,acetylene tanks should always be securely closed when empty1 not only for the above reasons but insomuch that each contains acetone1 which is likely to escape if the tank is thrown around4 ,acetone is very costly and used extensively in the manufacture of smokeless powder1 so that at times it is hard to replenish4 7#dj7 ,oxygen has an affinity for oils and greases1 and should not be allowed to come in contact with them1 especially in confined places1 as a spontaneous combustion may result4 ,oils and greases should never be used around oxy-acetylene welding apparatus and on nearly every apparatus on the market the words 8,use no oil10 will be found4 ,despite this precaution1 however1 many times ignorant operators will be found squirting oil into the holes around the regulator cap1 and through the gauges1 in order1 as they say1 to allow them to work easier4 ,this use of oil should be discouraged1 and the sooner the better4 ,,chapter ,,iii ,,shop ,,equipment 7#da7 ,in equipping a shop for welding1 in addition to the welding apparatus1 the operators are many times undecided whether it is advisable to have a planed metal or a brick top table to use for welding purposes2 each has its advantages1 but were there a choice of one or the other1 it is suggested that the brick-top table be used4 ,the theory of having a planed metal top for lining up work does not prove as satisfactory in actual practice as might be expected1 for the simple reason that the average welder generally places his metal in direct contact with this cold top1 and much of the heat which is supposed to go into the weld is conducted away by the table top1 producing a hard1 brittle weld4 ,in the case of cast iron1 these welds are generally porous4 ,then too1 the operator to a large extent depends upon the table top for lining up his work and does not study his contraction and expansion as thoroughly as he might4 ,the result is that many of his pieces warp in cooling4 ,to rectify the first objection it is advisable to cover the table top with asbestos paper as shown in ,fig4 #bh4 ,in the second place1 sometimes clamps are used to hold the work in position4 ,preheating without a layer of bricks on a metal-topped table is not to be recommended4 ,illustration3 ,,fig4 #bh4--,method of ,holding ,heat when ,welding on ,metal ,top ,tables4 ,asbestos paper1 ,p1 is laid upon the metal top1 ,m1 and the pieces1 ,a and ,b1 placed upon ,p in such a manner that the weld can be made at ,c4 ,the asbestos paper prevents too much heat escaping from the bottom of the weld4 ,illustration3 ,,fig4 #bi4--;,a ,fire-brick ,table for ,welding4 ,angle iron measuring #b by #b by inches is welded together in the manner shown and covered with fire-bricks which measure #b by #d by #i inches4 7#db7 ,a fire-brick table1 made up along the lines shown in ,fig4 #bi1 is very easily constructed and can be used for all sorts of jobs4 ,it is well to have everything clear around the legs and have no braces to cut the operator on the shins or to interfere in any way with his work4 ,the best fire bricks obtainable should be used4 ,a large number of extra bricks should always be on hand for they come in very handy in most of the welding operations1 and in fact to conduct a welding shop without fire bricks could almost be likened to a blacksmith's shop without an anvil4 ,besides being used for table tops1 preheating furnaces of a temporary nature may be built and the bricks used to jack up and align many jobs which could not be handled otherwise4 7#dc7 ,an emery wheel plays a very important part in a commercial welding shop1 insomuch that rust1 scale1 and unnecessary metal can be removed in a very short time by its use4 ,a flexible shaft attachment should be on hand1 if possible1 or a portable grinder of some kind1 for in many cases where the casting1 or the piece being worked upon is too heavy to bring to the emery wheel1 the wheel can be brought to it and many places ground down by its use that would be impossible with a stationary grinder4 ,illustration3 ,,fig4 #cj4--,one ,shop in which ,instruction in ,steel is being ,given1 at the ,ordnance ,welding ,school4 ,note the construction of the welding tables4 ,two or more may be placed together1 to give as large a surface as desired4 7#dd7 ,many times when working near a hole which may be threaded1 the welder has much difficulty in keeping his metal from entering the hole4 ,at other times it is necessary to back up preheated work such as aluminum1 to prevent its collapsing4 ,ordinary clay or putty cannot be used for this purpose4 ,the simple reason being that when metal is heated it expands and the clay or putty in giving off its moisture contracts1 showing two opposite reactions4 ,retort cement is a name given furnace cement mixed with shredded asbestos1 this1 as well as carbon flour1 has been found to be very satisfactory for filling in holes and backing up pre-heated work4 ,retort cement is purchased in airtight containers1 hardening very quickly when brought in contact with the air1 so at all times it should be kept in containers similar to those in which it is purchased4 ,it cannot be reclaimed once it is hardened4 7#de7 ,a blacksmith forge will be the medium of saving much valuable gas and time in a welding shop4 ,it will heat up parts to be welded in very short order and while in this condition they may be welded and then thrown back into the forge and allowed to cool very slowly4 7#df7 ,several pails of water should always be located where welding is being done to prevent fire from flying sparks2 to cool the torch tips and filler-rods1 when working on large jobs2 to keep certain parts of work being welded cool1 and to harden or temper other parts4 7#dg7 ,a simple and efficient manner of handling flux in the welding shop has puzzled many welders1 on account of the flux containers being easily upset1 their inaccessibility and the action of the air upon large quantities of flux4 ,a simple method of overcoming this is to cut in two1 a two and one-half or three-inch pipe coupling and mount it by welding on a square piece of one-eighth inch plate1 as shown in ,fig4 #ca4 ,this type of container is very hard to upset2 may be used when working on preheated jobs2 is easy to get at on account of its shallow nature1 and1 as it only holds a small amount of flux1 it can be cleaned out frequently and a fresh flux will always be available4 ,illustration3 ,,fig4 #ca4--;,a ,good ,flux ,container for the ,welding ,table4 7#dh7 ,additional equipment beneficial to the welder will be a quantity of various sized carbon rods and blocks2 asbestos paper2 goggles2 ,v-blocks for lining up shafts and an assortment of mechanics' tools1 such as wrenches1 hammers1 chisels1 hack-saws1 and other things which might be used in dissembling or assembling various kinds of machinery4 7#di7 ,another important item which is generally overlooked in the average welding shop is the question of ventilation4 ,although the welding flame itself contains no objectionable gases1 those from fresh charcoal preheating fires1 those given off when some of the alloys of the filler-rods are melted when brass1 copper1 and other metals are being worked on1 and from gas engine exhausts are not desirable4 ,at times they will give the operators violent headaches unless means are taken to carry them off4 ,the ventilation should be such that it will not directly affect the work4 ,drafts are to be avoided as much as possible1 for many times they will warp pieces being preheated if allowed to come in direct contact with them4 ,it is a good thing to remember that indirect ventilation and plenty of it is a prime requisite in a good welding shop4 ,,chapter ,,iv ,,apparatus ,,repairs 7#ej7 ,occasionally in setting up a welding apparatus1 a leak may be noticed along the lines1 some time after the plant is in operation4 ,leaks on either the oxygen or acetylene lines are to be considered dangerous as well as costly and therefore to be avoided at all times4 ,when the cylinder valves are closed on the drums containing the gases1 and the hands on the low-pressure gauges of each regulator are seen to drop or reduce their pressure when the torch valves are shut off and allowed to remain so1 this is an indication that there is a leak between the regulator and the torch4 ,it is not desirable to use a match or a flame of any kind in testing for leaks4 ,there are various methods employed by the cautious welder1 but about the best of these is a soapy solution of water1 which is kept in a can at all times and is applied with a paint brush4 ,if this solution is applied to any leaky part1 bubbles will form immediately and the leak will be located4 7#ea7 ,at times1 when working in isolated places1 where repairs cannot be had1 and no means have previously presented themselves for testing out the cylinders or the apparatus as a whole1 it may be found that the threads or ground seat on the cylinder valve of the regulator which is connected will be in such a condition that a leak is in evidence4 ,or it may be that the threads will not permit the seat being drawn up sufficiently to make it airtight4 ,in cases of this kind1 the welder must find some means of proceeding with his work1 and while it will be impossible for him to use white lead or any oily substance with safety1 he may stop the leak with litharge or lead oxide mixed with a small quantity of glycerine4 ,a string soaked in this solution may be wound around the main connection and the swivel nut screwed up to the seat as far as it will go4 ,if allowed to harden for a short time1 the litharge will set and a very satisfactory temporary repair will be effected4 ,illustration3 ,,fig4 #cb4--,method of ,attaching ,hose to ,connection so it cannot ,pull or ,blow off4 7#eb7 ,the method shown in ,fig4 #cb of attaching connections to hoses so that they will not blow off when pressure is applied is a very simple and effective means of overcoming this difficulty4 ,undoubtedly it will assist some operators in solving the trouble that has been occasioned by the ordinary hose clamps1 especially when doing cutting or heavy welding work where the gas pressure is considerably higher than usual4 ,the wire used should be large enough to prevent cutting the fabric in the hose4 7#ec7 ,an injured hose which may leak should never be used after the leak is noticed unless some means are taken to repair it4 ,the use of tape in trying to repair hose on an oxy-acetylene welding outfit should never be permitted4 ,the most efficient way of overcoming an injury of this kind is to cut the hose at this part and insert a piece of pipe4 ,the ends of the hose are then wired to this pipe and a union is thereby effected which will generally outlast the life of the hose4 ,special connections for this purpose are put out by most welding companies1 so that a supply may be on hand if hose trouble is expected4 7#ed7 ,when transporting welding apparatus1 occasionally the 8cross-bar0 on the regulator is lost and many times the operators do not know what is to be done4 ,the purpose of the 8cross-bar10 as we have already seen1 is only to apply pressure on the diaphragm springs1 so that if a set screw of the same diameter and same thread as those of the 8cross-bar0 can be found and screwed into its place with a wrench1 a section of filler-rod can be welded across the top of it and the use of the regulator will not be impaired4 ,if a special thread is used by any particular company1 a piece of brass or iron can be turned down in a lathe to fit4 ,illustration3 7,courtesy of the ,bastian-,blessing ,co47 ,,fig4 #cc4--,various ,types of ,adaptors ,used to ,connect ,regulators to ,cylinders having ,different ,connection4 7#ee7 ,the manufacturers of practically all regulators use the quarter-inch tapered pipe thread in attaching the cylinder connections to the regulator and do not depend upon the threads being gas-tight1 so they solder them in4 ,there are various types of cylinder connections put out by different manufacturers of the gases and occasionally it may be necessary to use a cylinder of gas which contains a different connection than is supplied on the regulator4 ,various adapters1 such as shown in ,fig4 #cc1 are supplied to overcome this difficulty1 but at times the operator is confronted with the very embarrassing situation1 of having a cylinder of gas and his regulator of different connections1 but no adapter suitable4 ,this predicament is usually found when some very important work is to be done and sometimes far from a supply depot4 ,at times the operator may have an adapter which will fit the cylinder but not the regulator4 ,if this is the case1 his difficulty can be very easily overcome1 for generally all adapters are made of two parts1 8sweated0 together1 and have the same quarter-inch tapered thread as used in the cylinder connections on the regulator4 ,the adapter can be separated1 the tank connection removed and the correct connection 8sweated0 into the regulator4 ,illustration3 7,courtesy of the ,u4,s4 ,gauge ,co47 ,,fig4 #cd4--,showing ,solid-front and ,hinged-back ,features of a 8,safety-first0 ,high-pressure ,oxygen ,gauge4 7#ef7 ,most gauges used in the oxy-acetylene industry to indicate gas pressure are of the ,bourbon type4 ,the most recent types of the oxygen high-pressure gauges are constructed with a hinged back and a solid front1 which means that should an oil or foreign matter enter the gauge from any source whatsoever and tend to burst it1 the back would be blown off and there would be no glass that could possibly fly around4 ,this is a safety device which has been welcomed with much enthusiasm on the part of the oxy-acetylene industry4 ,when leaks occur in gauges1 it is always best to remove the gauge from the regulator1 stopping the hole temporarily with a pipe plug and return the gauge to the manufacturers for repair4 ,these gauges are very delicately constructed and can be rendered useless if handled by the inexperienced4 ,a great many times after the case of the gauge has been jarred or loosened1 the screws connecting this case to the inside working mechanism are tightened up1 breaking the soldered connection holding the spring tube on the inside of the gauge4 ,this causes a leak which can be repaired quite easily if the operator is able to solder it4 ,it must be remembered1 however1 that if the flame is brought in contact with any of the springs that their tension will be lost and that the gauge may not operate correctly after this repair is made unless great care is exercised4 ,illustration3 ,,fig4 #ce4--;,a #cjjj-pound ,high-pressure ,oxygen ,gauge4 7#eg7 ,undoubtedly there are many welders who in beginning to operate their welding apparatus conclude that their gauges must be at fault when they show a reading after apparently all pressure has been released in closing down the apparatus4 ,it is to avoid the impression that the gauge is at fault that time is here taken to show that even though the cylinder valve is closed and the 8cross-bar0 on the regulator screwed out that when the torch valves are opened to drain the lines there will still be a reading on the high-pressure gauge if the regulator seat is in good working order4 ,it is simply a case of gas being trapped between the regulator and the cylinder valve4 ,to reduce this reading it is only necessary to screw in the 8cross-bar10 thus opening the regulator seat4 ,this could be avoided if the cylinder valve were closed first and the torch valves opened while the regulator 8cross-bar0 were still screwed in1 then as soon as the gas had left the line1 the torch valves could be closed and the 8cross-bar0 on the regulator could be screwed out until free4 ,,chapter ,v ,,preheating ,,agencies ,illustration3 7,courtesy of the ,messer ,mfg4 ,co47 ,,fig4 #cf4--;,a ,large ,job ,prepared for ,welding4 7#eh7 ,,preheating1 as applied to oxy-acetylene welding1 means the application of heat to the article to be welded in some manner which is usually different than by the welding flame itself4 ,charcoal1 coke1 kerosene1 crude oil1 coal and natural gas are used for this purpose4 ,the principal reasons for pre-heating parts to be welded are3 ,to take care of the effects of contraction and expansion on the confined ends2 to save time1 gas1 and material2 and to make a better weld by making it quicker and with less chance of burning up the metal4 ,illustration3 7,courtesy of the ,messer ,mfg4 ,co47 ,,fig4 #cg4--,showing how ,large ,work can be ,covered with ,asbestos ,paper when ,preheating4 7#ei7 ,on account of the ductile qualities of steel1 there is not quite as much heat used in preheating1 to take care of the contraction and expansion1 as in cast iron4 ,on brass work a very dull red heat is considered sufficient1 or otherwise the alloys might burn out4 ,when preheating aluminum1 there will be no change in color as the heat is introduced1 so other methods are used to determine the correct temperature4 ,three methods are used for this purpose by most welders4 8,half-and-half0 soldering wire will usually melt when applied to the surface of aluminum which is preheated to the proper state2 the puddle stick when drawn smartly across the heated surface should scrape off the oxide and leave a clear blue streak if the work is in condition to be welded2 and if a medium-sized tip is brought down so that the neutral flame just touches the surface for a second or two1 the metal will sweat1 if at the proper temperature1 and small globules which have the appearance of mercury will stand out on the surface4 7#fj7 ,the beginner must study contraction and expansion in order that he may know when and where to apply it in figuring out his work4 ,many welding jobs have turned out to be failures through lack of knowledge in this respect4 ,take1 for example1 a water-cooled cylinder block of the ordinary gas engine2 the water jacket may be broken when the water is allowed to freeze in it4 ,this problem has certainly confined ends1 but some welders have attempted to weld such jobs cold1 that is1 without preheating1 and possibly have succeeded in executing what they thought was a very fine weld1 but upon examination1 have discovered that the cylinder walls1 which are very accurately machined1 have been warped to such an extent that the block is rendered useless4 ,this is strictly a 8preheating0 job1 and the cylinder should be brought to a dull red heat if the best results are to follow4 ,as has been stated elsewhere in this volume1 the weld should not be considered successful unless the piece worked upon can be returned to a usable state4 7#fa7 ,several different fuels have been mentioned1 all of which can be used for preheating purposes4 ,charcoal is considered the best agent for general welding1 as it gives off a very steady heat which will gradually be absorbed by the article worked upon1 bringing it to the heat desired and holding it there throughout the welding operation4 ,it will then permit very gradual cooling1 as this sort of fire takes a long time in dying--a desirable asset in work of this kind4 ,on account of the scarcity of charcoal and its high price1 other agencies are used and chief among them are torches using kerosene1 crude oil1 or city gas1 as a fuel4 ,these usually heat up the work more quickly1 but care in their manipulation is necessary4 ,a preheating torch to be used in conjunction with city gas can be very easily constructed1 if the details of ,fig4 #ch are observed4 ,this proves to be a very efficient and cheaply constructed apparatus4 ,illustration3 ,,fig4 #ch4--,preheating ,torch1 ,constructed of ,black ,iron ,pipe1 for ,burning ,city ,gas4 7#fb7 ,when work is being preheated1 it is best to have it protected from all drafts1 to prevent warping4 ,possibly the most extensively used material for building up temporary ovens to hold the heat and protect the work from the air currents is fire brick and with it asbestos paper4 ,when setting up an ordinary casting for preheating1 these bricks are built up in builder's fashion1 about four inches away from the piece itself1 as shown in ,fig4 #ci1 and practically level with the top of the piece4 ,if charcoal is to be used1 draft spaces are left in the first row of bricks as shown1 and the charcoal ignited through the openings with the welding torch4 ,the work to be welded should have the line of weld at the top if possible and be set up from the floor1 or the surface upon which the oven is resting1 on one or two fire bricks1 in order that the full benefit of the heat will be received4 ,asbestos paper is then laid across the top1 and the oven will appear as in ,fig4 #dj4 ,when starting the fire1 a layer of charcoal1 a matter of two or three inches thick1 is at first used1 but as the chill is taken off the piece the oven can be filled to the top1 and usually this is enough to complete the work4 ,illustration3 ,,fig4 #ci4--,temporary ,preheating ,oven1 ,built of ,fire ,brick4 ,illustration3 ,,fig4 #dj4--,temporary ,preheating ,oven of ,fire ,bricks ,covered with ,asbestos ,paper4 7#fc7 ,in order to protect the operator1 when working over hot fires1 it is recommended that the asbestos covering be left on1 and that only a small section immediately in the vicinity of the weld be removed1 which can be accomplished by cutting a 8,u0 in the paper as shown by the dotted lines in ,fig4 #dj4 ,this can be turned back1 exposing the place which is to be welded1 and at the same time protecting the operator1 to a large extent1 from the unnecessary heat4 ,when the weld is finished1 this lap can be turned back and the piece allowed to cool4 ,on pieces which require turning and must be welded in several different positions1 the preheating oven1 as it is called1 should be built considerably larger1 to provide for handling the work4 ,it must be remembered that during the entire operation1 the piece should be left inside the oven and should not be removed to a welding table4 ,some beginners make the mistake of doing this4 ,when welding with the charcoal in closed rooms1 during the winter months1 the fumes will be found to be very disagreeable and means should be taken to provide indirect ventilation1 otherwise the welders will be troubled with headaches and smarting eyes4 ,illustration3 ,,fig4 #da4--,showing ,how ,oven is ,built when ,preheating ,torch is to be ,used4 ,torch is ,shown at 7,a74 7#fd7 ,when using preheating torches1 the ovens are built much closer to the work and do not have the openings along the bottom row of bricks4 ,they are made as tight as possible1 and in some cases it will be found advisable to build up the walls with two layers of bricks1 with asbestos paper between them1 in order to hold the heat and cause the work to heat up in a more uniform manner4 ,a hole is left in one end of the oven1 through which the flame of the preheating torch is introduced as shown in ,fig4 #da4 ,it is not thought best to have the torch flame come in direct contact with the work which is being preheated1 and a baffling plate of metal or brick is placed directly in front of the flame1 in order to spread it around the oven4 ,judgment will have to be used in all such work4 7#fe7 ,the setting up of the work1 when preheating1 is an important point overlooked by many welders1 especially so in the case of aluminum4 ,care should be taken to see that the work has a good solid setting and is braced at a sufficient number of points1 to prevent its sagging when in a preheated condition4 ,many times when working on rough surfaces1 a few firebricks distributed around the bottom of the oven with a dab of putty1 clay1 or retort cement1 placed upon them1 will form an excellent cushion upon which the work can rest and the operator may feel confident that no sagging will occur4 ,,chapter ,,vi ,,part ,,one4--,,welding ,,of ,,cast ,,iron 7#ff7 ,in order to know how to weld1 it is quite imperative that the operator first know the kind of metal he is to work on4 ,it is surprising to find how few welders know their metals thoroughly4 ,an incident might be cited where some welders depend upon the sparks given off by the emery wheel in determining the kind of metal they are about to weld4 ,they will approach the wheel2 grind off their work1 noting the sparks2 return to their welding table2 choose their filler rods and do their welding without any delay whatsoever1 much to the consternation of their fellow workers4 ,there are four simple ways in common use to distinguish between cast iron1 malleable iron1 and steel2 they are3 ,by the cross-section of a fresh break1 by application of the welding torch1 by the sparks given off when applied to the emery wheel and by the chisel test4 ,illustration3 ,,fig4 #db4--;,characteristic ,sparks of ,different ,irons and ,steels ,thrown off by an ,emery ,wheel4 ,wheel should be ,clean ,cutting and ,run about #gjjj ,feet per ,minute4 7#a7 ,shows cast iron4 ,no sparks unless impurities are present4 7#b7 ,is wrought iron almost free from carbon4 ,heated particles thrown from wheel follow straight line4 ,these become broader and more luminous some distance from their source of heat4 7#c7 ,illustrates mild steel action4 ,small amount of carbon present causes a division or forking of the luminous streak4 7#d7 ,shows the effect of increasing the carbon from #j4ej to #j4he per cent in mild steel4 ,the iron spark lines diminish3 the forking of the luminous streak occurs more frequently1 being subdivided by re-explosions from smaller particles4 7#e7 ,is a piece of carbon tool steel4 ,the iron lines are practically eliminated with the increase of the explosions and subdivisions1 causing display of figures4 7#f7 ,gives the spark of high-speed steel1 containing in addition to #fe per cent carbon1 other alloying elements1 chiefly tungsten and chromium4 7#g7 ,represents a manganese spark4 7,occasionally found in cast iron47 7#h7 ,shows spark thrown from old grade of 8,mushett0 steel4 7#i7 ,represents a magnet steel spark4 7#fg7 ,externally cast iron usually has some sand on its surface and its cross-section shows the grain to be fine1 even1 and to have a dull grayish color4 ,the surface of malleable iron contains no sand and its grain is very fine1 such as cast iron1 but slightly darker in color4 ,a very fine steel veneer is on all surfaces of malleable iron1 which is much lighter in color4 ,when the welding torch is applied to cast iron1 no sparks are given off1 but when applied to malleable iron a bright spark is thrown off which breaks in falling1 showing that the outside material is steel4 ,these sparks soon cease and the metal which is molten is covered by a heavy oxide or skin which recedes or draws away from the flame slightly1 showing a very porous cast-iron interior4 ,when brought in contact with the emery wheel steel sparks1 which are very luminous and break in falling1 are given off first in the case of malleable iron1 but they soon change to the dull red spark of cast iron4 ,when a chisel is applied to cast iron1 the iron chips off2 when applied to malleable iron the edge will curl up1 then chip off when the cast iron is reached4 ,the cross-section of cast steel shows a bright1 coarse1 silvery gray grain4 ,when the torch is applied a distinctively steel spark which is luminous and breaks in falling is thrown off4 ,when applied to the emery wheel steel sparks are thrown off2 when the edge is chipped by a chisel it will curl up4 ,illustration3 ,,methods ,,of ,,distinguishing ,,metals ,here are five methods1 any one or all of which may be used to learn the nature of common castings which might confuse the welder4 ---------------------------------------- -------------------------- ,no4 ,test4 ,malleable ,iron4 ,cast ,steel4 ,cast ,iron4 ---------------------------------------- -------------------------- #a ,outside ,generally smooth and,rough surface ,surface fairly ,appearance4free from all sand1 with sand in smooth but weighs about same evidence1 weighs generally shows as cast iron4 much more some sand4 than cast iron4 ---------------------------------------- -------------------------- #b ,cross- ,ring of bright steel,large1 bright1 ,fine1 uniform1 section crystals outside1 luminous1 silver dark gray1 ,test4 with darker iron crystals4 crystals4 crystals inside4 ---------------------------------------- -------------------------- #c ,emery ,wheel,few steel sparks and,bright1 luminous ,dull red sparks ,test4 then iron sparks sparks that that do not from interior4 break in falling4break4 ---------------------------------------- -------------------------- #d ,chisel ,surface will curl ,will curl before ,will chip off4 ,test4 and interior break breaking4 off4 ---------------------------------------- -------------------------- #e ,torch ,test4,gives way before ,gives forth ,gives no sparks flame and delivers bright sparks except where few sparks4 ,metal that break in there are becomes porous4 falling4 impurities4 ---------------------------------------- -------------------------- ,,fig4 #dc4 7#fh7 ,the metal in the filler-rod should be the same in practically all cases as the metal to be welded4 ,there are few exceptions to this rule1 but the principal one is that of malleable iron4 ,the cast iron in the rods is of a very good grade and generally much better than the piece to be worked upon4 ,to permit the ready flow of the rod and eliminate oxidation1 as much as possible1 three per cent of silica is generally used in the casting of filler-rods for cast iron welding4 ,piston rings and other scrap iron should not be used for filler-rods1 as they contain many impurities such as core-sand1 dirt1 grease1 etc41 which will ruin the weld4 ,it is disheartening to see some operators attempt to economize on the filler-rod4 ,it is not an uncommon sight to see several dollars' worth of gas and the same amount of the welder's time1 together with a few cents' worth of filler rods all lost1 and the operator's reputation ruined4 ,this1 because an attempt is made to save the few cents involved in the filler-rods by substituting a rod of a very poor grade4 7#fi7 ,a flux is not used1 as many suppose1 to cement the filler-rod to the metal4 ,it is used purely as a cleansing agent and may be likened to the acid used in soldering4 ,it does not act on the metal until the latter has reached the melting-point1 but then it starts to break up the oxides and clean the surface4 ,this action permits the metal to flow together more readily4 ,a cast-iron flux is always used in welding cast iron1 to break up the oxide1 because the cast iron itself will melt before the oxide and no matter how hot the metal is it will not flow together as long as this oxide is present4 7#gj7 ,to obtain the best results1 reliable fluxes should always be used4 ,occasionally an accident will happen to the flux can1 when the operator is on some isolated job and a substitute flux must be obtained at once4 ,equal parts of bicarbonate of soda 7cooking soda71 and carbonate of soda 7ordinary washing soda71 may be purchased from any grocery in the powdered form and mixed together thoroughly4 ,this will tide the welder over until he can return to the shop and replenish his supply4 ,illustration3 ,,fig4 #dd4--,whenever ,possible1 the ,beginner should 8,v0 ,his ,work1 and ,complete ,his ,weld from ,one ,side only4 ,on heavy work1 however1 it will be necessary to 8,v0 out from both sides1 as is here shown4 7#ga7 ,the flux is generally applied by means of the filler-rod4 ,one end is heated and dipped in the flux2 enough will adhere to break up part of the oxides1 on the ordinary-sized job4 ,the flux is carried to the work1 which should be at the melting-point and introduced between the flame and the metal4 ,oxides will break up immediately and the metal will flow together1 but it must be remembered that the flux has no action on cold or moderately heated metals4 ,the flux as has been explained is used to clean the metal and break up the oxides4 ,to the oft-repeated question1 how often should the flux be applied1 answer is made as follows3 ,as often as it is necessary to clean up the metal and break up the oxides4 ,all fluxes should be kept in airtight containers when not in use1 to keep their chemical contents in the very best condition and it is best to use only a small quantity of flux on the welding table at one time4 7#gb7 ,oxy-acetylene welding is purely a fusing process and the most important points to remember in executing a weld are1 to eliminate the entire crack in the fracture and to add the filler-rod without changing the character of the metal4 ,on thin pieces of metal it is possible to depend upon the force of the flame to entirely penetrate to the depth of the crack but on work three-eighths of an inch thick or over1 it is well to 8,v0 out or remove some of the surface metal around the crack in order to get down to the bottom4 ,by 8,v-ing0 we mean to chip or grind off each edge at an angle of approximately #de degrees1 so that the opening will form an angle of #ij degrees where the two pieces come together1 with the crack at the bottom portion of the 8,v40 ,this should ,,not be ground down to a knife edge1 for it will readily burn up4 ,it is preferable to leave about one-eighth inch along the line in order that the pieces will fit together and the proper alignment may be obtained4 ,if two pieces of cast iron have been prepared in this manner the neutral flame of the welding torch is brought down in such a manner that the tip of the cone just licks the metal4 ,the heat is not applied directly to the line of weld to start with1 but rather to the surrounding part4 ,this is done in order to get the entire locality in a condition which will not withdraw too much of the heat from the line of the weld1 once the fusing is begun4 ,if it is found that the tip will not produce enough heat to bring the metal to a red heat in a fairly short time1 a larger tip should be used4 ,illustration3 ,,fig4 #de4--,starting a ,cast-iron ,weld4 ,illustration3 ,,fig4 #df4--,reinforcing a ,cast-iron ,weld4 7#gc7 ,no set rule can be given as to the sized tip to be used on various kinds of metal4 ,it will largely depend upon the welder's ability and judgment4 ,when the metal is brought to red-heat1 the neutral flame or cone is brought into contact with the lowest portion of the 8,v0 and held there until it is seen that the metal is melted on both sides4 ,the filler-rod1 which has previously been heated at one end and dipped into the flux so that an amount adheres to the end of the rod1 then carries this flux to that portion of the weld which is under way4 ,enough flux is blown off the rod into the weld to clean up the surface and permit the metal flowing together4 ,the crack should be melted together all along before any additional metal is added1 for the elimination of the crack is extremely important4 ,it might be noted that as soon as the metal begins to flow freely the neutral flame should be raised a short distance from the work in order to better control the molten metal4 ,in order to build up the metal to the original state along the line of weld or perhaps reinforce it1 the sides and bottom of this 8,v-ed0 out part are then brought to a molten state and held there while the filler-rod which brings up more flux is stirred into this metal and the end melted off4 ,in this way the flame does not come in direct contact with the filler-rod and is used only to keep the metal in a molten condition4 ,as much of the filler-rod can be melted off as is thought necessary to bring the weld to the normal condition of the metal or an additional reinforcement can be built up1 if it is thought advisable4 ,if care is taken in the above procedure1 many of the blow holes and hard spots in the weld will be eliminated1 for any impurities that might gather will be displaced by the melted metal and will float to the top4 ,in cooling a weld of this kind1 care should be taken not to permit any sudden chilling for this will tend to harden the weld4 ,it is best to cool it slowly by burying it in slack lime1 ashes1 or wrap it with asbestos paper to keep the air from it as much as possible4 ,illustration3 ,,fig4 #dg4--,this ,problem does not ,require ,preheating to ,care for ,contraction1 as the ,ends of ,a and ,b are not ,confined4 7#gd7 ,there may be a great many causes for blow holes and hard spots in the weld1 but probably they can all be traced directly to the lack of heat4 ,it must be remembered that welding is a fusing process and heat is absolutely essential4 ,therefore it should not be used sparingly4 ,the application of heat always causes expansion4 ,there are no exceptions to this rule1 likewise upon cooling the metal there will be a contraction4 ,outside of the actual welding1 that is1 the fusing of the metal into a homogeneous mass1 perhaps the greatest problem that the welder has to confront is the expansion and contraction of his metals4 ,whenever the ends of two pieces of metal which are to be welded are free to move1 or even one end1 there will be no difficulty encountered with contraction and expansion1 but if these ends are confined1 it is an entirely different problem4 ,illustration3 ,,fig4 #dh4--,preheating ,problem4 ,ends of ,bars ,a and ,b are ,confined4 7#ge7 ,to illustrate this point more clearly1 the following very simple example will be given4 ,in ,fig4 #dg we have two bars of metal ,a and ,b which have been beveled off or 8,v-ed0 out as shown at the point ,c4 ,now as soon as the heat is introduced at ,c there is bound to be an expansion of the metal at that point4 ,naturally if the pieces were heated slowly and for a considerable distance1 the cool ends of these bars would be forced outward4 ,we will assume that the heat is introduced very rapidly and the metal is brought to a molten state2 that instead of the contraction forcing the cool ends outward1 whatever expansion there is1 is taken care of1 at the weld1 for the metal when melted will readily push together4 ,it is also assumed that the bars are heavy enough to overcome what slight force might be in evidence from the expansion4 ,a weld is then made and allowed to cool4 ,as it cools1 there is bound to be a contraction along the line of the weld and the welded piece will be slightly shorter than the work before the weld1 for it will draw in the pieces ,a and ,b4 ,as can be seen1 there is no particular force preventing the contraction of such a weld for the ends are free to move4 ,however1 let us turn to ,fig4 #dh1 which constitutes an entirely different problem4 ,it might seem that the ends ,a and ,b appear the same as ,a and ,b in ,fig4 #dg1 but such is not the case4 ,the ends farthest from the weld are confined1 held in place by a heavy frame which does not permit their free movement4 ,when heat is introduced at the point of welding ,c1 about the same action takes place as in the previous problem1 but as soon as the weld commences to cool let us see what happens4 ,the bar ,a,b must be shortened so there is an inward pull on the bars ,d and ,e4 ,if this work were cast iron or aluminum it would certainly be broken by the strains set to working and would naturally break at ,c1 where the metal is still hot4 ,if it were steel or one of the ductile metals1 it might twist and warp in its endeavor to overcome these internal strains4 ,this illustrates in a very simple manner the difference between what is known as a 8cold0 and a 8preheating0 job4 ,in the first no provision is made for expansion and contraction4 ,in the second means are taken to overcome these important factors4 ,in order to provide for the successful welding of the second problem1 it is only necessary to heat up the bars ,x and ,y about the same distance as the center will be heated1 and keep them in that condition while executing the weld at ,c1 then allowing the whole to cool gradually4 ,,part ,,two4--,,welding ,,of ,,cast ,,iron 7#gf7 ,before commencing to weld1 or even turning on the gas1 it is well to see that all preparations have been made and all materials on hand to bring the weld or whatever job it may be1 to a finished state4 ,illustration3 7,courtesy of ,ben ,k4 ,smith1 ,u4 ,s4 ,welding ,co47 ,,fig4 #di4--,this ,locomotive ,cylinder was ,welded at the ,saddle1 near the ,frame4 7#gg7 ,as a specific example of a simple welding operation let us consider that two cast-iron bars1 measuring one by six inches and twenty-four inches long are to be welded end to end4 ,to start with it would be necessary to 8,v0 off the ends that were to be joined at an angle of about #de degrees1 leaving about one-eighth inch along the bottom edge to line the metals up with and to see whether they are in proper position4 ,if the bar were to measure exactly forty-eight inches when finished it would be necessary to move these bars apart about one-sixteenth of an inch in order to provide for their contraction4 ,it is assumed that the weight of the bars would be sufficient to prevent their pushing apart when the line of the weld is brought to a molten state and that the expansion will be taken care of within the weld4 ,the bars after being lined up are ready for welding1 but there are such things as filler-rods1 flux and goggles that are necessary to have on hand before starting to work4 ,it is well to have a few fire bricks1 a little asbestos paper and a bucket of water convenient1 in case these things are needed4 ,the acetylene gas should then be turned on and ignited4 ,a sufficient pressure should be passing through the regulator1 when using a medium1 or high-pressure apparatus1 to cause the flame to leave the torch tip about twice the distance of the diameter of the orifice of that particular tip4 ,then turn on the oxygen until a neutral flame is obtained4 ,on some torches it is necessary to make a second adjustment by turning on a little more acetylene gas and still more oxygen1 until a goodly sized neutral flame results4 ,apply the flame to the pieces1 so that the neutral flame will just lick the surface of the metal4 ,move the torch slowly forward and backward on each side of the 8,v0 until the two edges are a dull red color1 or better still a bright cherry red1 then hold the torch stationary until the metal in the 8,v0 nearest to the operator commences to melt4 ,then bring the filler-rod end in contact with the flame to get it heated and plunge it into the flux which should be near at hand4 ,enough flux will adhere to break up the oxides and by placing the rod between the flame and the metal1 enough flux will be introduced to allow fusing of the metal4 ,proceed in this manner until the metal in the bottom of the 8,v0 is properly fused throughout its length4 ,do not add the filler-rod1 up to this point unless necessary4 ,in holding the flame1 see that the preheating flame will heat the parts yet to be welded4 ,the weld should be made away from the operator4 ,after the metals along the bottom have united and a good foundation has been obtained1 then start the weld at the beginning once more1 working the flame across the piece1 in the same manner as before2 bringing the metal to the molten state and stirring the filler-rod in it4 ,as the filler-rod melts1 the amount of molten metal naturally increases and the flame is moved along the weld as fast as the metal is added4 ,it is important that the metal is in a molten condition4 ,it is almost impossible to get too much heat on this type of work4 ,build up the weld slightly higher than the original piece4 ,it may be found in finishing up the corners that the velocity of the gases or the force of the flame will be sufficient to blow the melted metal away4 ,this may be overcome by directing the flame at a different angle1 and will cause no difficulty after a little practice4 ,trouble1 too1 may be experienced on thin cast-iron sections by having the metal collapse through the force of the flame1 but this can be remedied in the same manner4 ,while the weld is still in a heated condition1 it is possible to finish it by scraping the surplus metal off with the side of the filler-rod1 the chill of which has been taken off before it is allowed to come in contact with the molten metal4 ,another popular method that will produce even better results is to use a very heavy rasp file to bring the weld down to the measurements desired4 ,during all of the previous operations the flame never leaves the line of weld4 ,when the weld is completed1 the torch is shut down by turning off the oxygen first1 and then the acetylene1 and the welded bar is covered up to prevent its cooling too rapidly4 ,,part ,,three4--,,welding ,,of ,,cast ,,iron 7#gh7 ,problems in expansion and contraction should not be difficult1 if it is remembered that heat causes expansion and the withdrawal of heat1 or cooling causes contraction4 ,as previously stated1 when the ends of the pieces which are being welded are free to move1 there is not much danger of having contraction strains set up4 ,where the ends are confined1 measures must be taken to overcome this4 ,in welding large pulley wheels1 for example1 it may be advisable to do the job without taking time to preheat4 ,breaks may be in evidence at any part of the wheel and generally the ends are confined1 such as in the case of a spoke4 ,if it is borne in mind that the expansion will take care of itself1 the contraction is the only consideration1 in a case of this kind4 ,the welder will see that if he can spring the edges apart a sufficient amount to provide for the spoke coming back to normal when welded1 he will have no difficulty4 ,the way to proceed in a case of this kind would be to open the rim by sawing it and then introduce a jack or some sort of a wedge between the hub and the rim4 ,this will open the crack in the spoke the amount desired4 ,as soon as the weld is executed and while still hot1 the jack is removed to permit the rim being drawn in4 ,later the rim can be welded1 by introducing jacks between the spokes and the same procedure followed4 ,it always must be remembered that provision must be made for the contraction1 even though it be only one thirty-second or one-sixteenth of an inch4 ,the distance will depend entirely upon the welder1 as some operators use small tips and cover a small area1 while others employ larger tips and cover twice the area4 ,it is therefore impossible to set any specific distance and each welder should try to figure this out for himself4 ,illustration3 7,courtesy of ,torchweld ,equipment ,co47 ,,fig4 #ej4--,large ,cast-iron ,gear ,wheels4 ,although the ,face on ,these ,gears ,measured #aj ,inches1 ,new ,teeth were ,added by ,blanking ,in1 as ,shown in the ,right-hand ,view1 and ,later ,machined4 7#gi7 ,there are many jobs not of a preheating nature that at times cause perplexity on the part of the welder4 ,a good example of this is a cast-iron gear wheel4 ,a number of its teeth have been broken out4 ,now there are three very common ways of building up or repairing such castings4 ,first by aid of carbon blocks1 cut to form and the teeth cast in by the use of the torch2 second1 by blanking in the space between the teeth and then sawing out the individual tooth or cutting it out with a milling machine or shaper2 third1 by building up each tooth with the welding rod and torch1 and later dressing it down with a file4 ,one very important point must be uppermost1 when dental work on gears is being done1 a good foundation is necessary1 for regardless of how well the tooth may be shaped1 if it is not firmly secured to the wheel itself1 it will be of very little value4 ,another very important point is in the finishing of such gears1 to see that the teeth which have been added correspond in the pitch and mesh exactly as the others do4 ,the importance of seeing that things of this nature are machined correctly should not require mention1 but it has often been found that machinists are very careless about finishing this kind of work and if anything goes wrong1 the welder is naturally at fault4 ,therefore it is always well to put the gears which have been welded back into place and turn them over slowly by hand to see that they are in good condition before the power is turned on4 ,in allowing this kind of work to cool after it has been welded1 some operators permit it to be hurried1 with the result that there may be hard spots to confront the machinist when finishing4 ,if he ruins one or two of his cutters he will naturally frown upon all welding work4 ,it is therefore desirable for this and many other reasons to have the weld come out as soft as possible1 and great care should be exercised in cooling4 ,any weld that is subjected to machining1 allow it to cool slowly in slack lime1 in ashes1 or cover it securely with asbestos paper4 ,occasionally it may be found difficult to find sections of carbon blocks which will take care of a job of this kind4 ,many welders who have had to run around the country1 and do jobs in isolated places1 have found that the carbon centers1 from the ordinary dry cell batteries1 which may be found practically everywhere in a discarded condition1 can be shaped on an emery wheel and patched together in a manner that will permit their use4 ,however1 when such are used1 it is quite necessary that they be heated a little with a torch beforehand1 in order to drive out any chemicals or acids that may be contained in them4 ,unless these chemicals are removed1 the molten metal coming in direct contact with them might be injured to a considerable extent4 ,illustration3 7,courtesy of the ,oxweld ,acetylene ,co47 ,,fig4 #ea4--,this ,view ,shows new ,teeth being ,welded in an #h-;ft4 ,cast-iron ,gear1 ,weighing over #e ,tons4 ,note the ,improvised ,preheating ,oven4 7#hj7 ,ofttimes there are castings upon which parts wear off in a very short time4 ,there may be very little strain upon these parts1 yet the constant wear will weaken them in time4 ,it is well to remember the action of a carbonizing flame when executing work of this kind4 ,introduce an excess of acetylene when finishing up the work4 ,it will be found that with a strongly carbonizing flame1 carbon will be taken up by the molten metal and the finished weld will be considerably harder and will wear longer than if it were executed by a neutral flame4 ,an abrupt cooling will chill the metal on the surface and make it wear longer than it would otherwise4 ,,part ,,four4--,,welding ,,of ,,cast ,,iron ,illustration3 7,courtesy of ,ben ,k4 ,smith1 ,u4 ,s4 ,welding ,co47 ,,fig4 #eb4--,view of ,locomotive ,cylinder with ,three ,jackets #c ,inches ,thick4 ,this job weighed over #af ,tons and ,required ,fifty-six ,hours of ,welding4 ,illustration3 7,courtesy of ,torchweld ,equipment ,co47 ,,fig4 #ec4--,various ,types of ,cylinders before and after ,welding4 7#ha7 ,the true index as to the success of a weld will depend entirely upon the finished job4 ,if it is usable1 i4e41 if it can be put back into service again and give satisfaction1 it may be considered a successful weld4 ,if a piece were to be warped1 distorted1 contain hard spots which could not be machined1 or have internal strains1 which would not make it safe for use 7such as fly-wheels71 it could not then be considered satisfactory and it would be only wasted energy4 ,perhaps one of the most common jobs in the ordinary commercial shop1 and one which is the most abused1 is the common cast-iron cylinder block found on the gasoline engine4 ,this is so constructed that there are two walls of metal1 very thinly cast2 the innermost being the cylinder wall1 and the outermost a water-jacket4 ,the cylinder wall is machined very accurately to accommodate pistons moving at a very rapid rate1 up and down and yet holding compression4 ,the upper part of the cylinder is called the head1 and generally has two or more valve seats which must be in alignment with the valve guides to make an airtight seat for the valves4 ,now this water-jacket is usually very thin1 perhaps three-sixteenths to one-quarter inch in thickness1 and when there are two1 three1 four1 or more cylinders cast in one block1 there are bound to be internal strains set up in casting within the piece itself4 ,these strains are removed to a large extent by baking the rough casting before machining4 ,generally there are some strains left in every cylinder block of this nature4 ,if the water in the water-jacket freezes or some other force comes in contact with the thin castings which constitute a block1 the metal will give way at its weakest point1 and the welder is usually called upon to repair it4 ,at times these cracks are exceedingly small and the temptation is to braze or attempt to weld the small portions4 ,however1 as soon as there is heat introduced into the water-jacket and not into the cylinder wall1 there are certain to be strains set up which1 if sufficient1 will distort the cylinder and make it useless unless it is rebored4 ,the sooner welders realize that work of this nature must be preheated throughout1 to a point as near melting as they can approach without causing the metal to scale1 before any welding is attempted1 the better success will be obtained in these lines4 ,it is quite necessary to line up the work well1 so that it will not sag when heated4 ,it is best to heat very slowly and cool in the same manner to insure the best results4 ,there are many preheating agencies1 such as oil-ovens1 preheating torches and the like1 but about the best and most reliable agent known is charcoal1 which heats up very gradually1 makes a good even fire and dies down slowly which is the manner desired4 ,occasionally cracks will be found in the combustion head of the cylinder4 ,it is very difficult to get the torch down inside the cylinder to execute this weld unless the operator has a special torch for this purpose4 ,even then it is difficult to keep the torch lighted when working over a newly made charcoal fire4 ,for this reason1 other means must be used when working on a job of this kind4 ,first the crack is accurately located1 then a piece is cut out of the water-jacket just over the crack by means of a chisel1 hack-saw or drill press4 ,never attempt to remove a piece of this nature with the flame1 for the introduction of heat may distort the piece at this time4 8,v0 out the crack in the combustion head and scrape off as much of the brown oxide and dirt formation as possible4 ,it is well to clean off more than needed and to even 8,v0 out the crack a greater distance than is thought necessary4 ,this will insure a good weld being made in one operation4 ,the cylinder is then preheated with the crack uppermost so that welding can be executed with the least possible difficulty4 ,while preheating is taking place it is well to tack the small section of the water-jacket which has been removed1 to the end of the filler-rod1 and place it too1 in the preheating oven1 with the end of the filler-rod projecting so that it will be available whenever needed4 ,when the cylinder is red hot the weld should be executed2 particular attention being given to see that each part of the metal is actually fused to prevent any leaks occurring later4 ,as a rule the welder can tell when he has made a successful weld by observing the flow of his metal1 and it will not be necessary for him to test out this cylinder weld before adding the water-jacket4 ,the piece of the water-jacket is then replaced2 it can be very easily handled by means of the filler-rod which has been tacked on4 ,weld this section securely in place and cover the piece of work with asbestos paper and permit it to cool with the dying fire4 ,when cold1 all port holes in the water-jacket should be closed and the cylinder tested for leaks4 ,this can be done by introducing water into the water-jacket and applying about fifteen pounds of air pressure4 ,wet spots will appear if there are any leaks4 ,if the cylinder is found tight it should be polished1 then oiled1 and the outside given a coat of filler or painted to make it presentable4 ,work is generally very much discolored when coming out of the fire4 ,a simple device for polishing the cylinder bore may be made by turning out a hardwood block about three inches long and a little less in diameter than the size of the piston4 ,this should be split as shown in ,fig4 #ed1 and wrapped with very fine emery cloth1 then put into the cylinder and a wedge placed between the two halves4 ,spread them apart so they will come in contact with the cylinder wall on all sides4 ,a screwdriver may be used for this purpose if necessary4 ,by screwing this into the cylinder its full depth1 with the aid of a little oil1 a very highly polished surface may be obtained4 ,illustration3 ,,fig4 #ed4--,suggested ,method of ,polishing ,cylinder ,walls of ,cast-iron ,cylinder ,block after it has been ,preheated4 ,illustration3 ,,fig4 #ee4--;,cast-iron ,cylinder ,block with ,part ,broken ,off4 ,illustration3 ,,fig4 #ef4--,showing how ,broken ,part on ,cast-iron ,block should be ,lined up before ,welding4 ,position ,greatly ,exaggerated4 7#hb7 ,another cylinder block job that generally causes more confusion than is necessary is brought about when welding on small lugs1 such as shown in ,fig4 #ee4 ,when welding these lugs on from the outside only1 they generally warp upwards in cooling and it is either necessary to build up the bottom side of this lug or to machine off the entire face in order to have the end square4 ,this can easily be overcome by permitting the lug to sag before welding and then dress off the small portion that continues to sag1 after it is welded1 rather than face off the whole surface4 ,see ,fig4 #ef4 ,,chapter ,,vii ,,part ,,one4--,,steel ,,welding 7#hc7 ,the term 8steel10 as used in the following pages1 unless otherwise specified1 will be the term applied to wrought-iron and low-carbon steels4 ,high-carbon and alloyed steels are to be considered only in advanced work and will therefore not be deemed a topic of interest to the beginner in laying his foundation4 7#hd7 ,the welding of steel is much more difficult than cast iron on account of the many points which must be observed4 ,in cast iron the metal is brought to a molten state and may be worked in that condition for some time without any apparent change in the characteristics of the metal4 ,a flux is used to break up the oxide or scale and the metal will flow very easily4 ,the flux is necessary because the oxide has a higher melting-point than the iron itself4 ,when working on steel1 it will be observed that just the reverse is true1 that its oxide has a lower melting-point than the steel and consequently no flux or cleaning powder is necessary when working upon it4 7#he7 ,a large quantity of steel kept in a molten condition by the flame acting upon it is very easily influenced4 ,the same area is not kept in a molten condition as with cast iron4 ,the heat does not hold to the vicinity of the weld nearly so much as in cast iron because of the greater conductivity of the metal4 ,if the flame is removed1 the molten metal will set almost immediately4 ,this means that the flame must be in contact with the metal at all times4 ,it must be a strictly neutral flame or else one of the two gases will be introduced into the weld and its strength will be materially affected4 ,the size of this flame must be such that too great an area will not be covered1 yet enough must be covered to keep the metal along the line of the weld in a molten condition4 ,if a carbonizing flame is used1 one which has an excess of acetylene1 such as was shown in ,fig4 #bc1 much carbon will be taken up by the metal1 producing a brittle weld4 ,if the flame is oxidizing1 that is1 contains an excess of oxygen which is noticed by the shortening of the flame and an accompanying hissing sound1 ,fig4 #be1 the metal will burn and a white foam will appear on the weld like a milky white glue4 ,this tends to weaken the weld4 ,this same effect will be in evidence if too large a tip is used4 ,on the other hand if the tip is too small not enough heat is obtained and the oxides and other impurities which may be present will not be allowed to float to the surface but will be trapped in the weld4 7#hf7 ,the filler-rod used on steel should be as near the same grade1 if not better than the metal to be welded and should be very low in its carbon content4 ,a pure grade of soft iron wire or mild steel will make a very good filler-rod for ordinary purposes4 ,the size of this filler-rod is very important1 for it should fuse at the same time as the metal being worked upon1 and unless it does this the weld will not be satisfactory4 ,if the filler-rod is too large it will not be at the fusion point when the work is1 and will not fuse with it4 ,if the rod is brought to a melting-point the work will have too much heat and will burn4 ,on the other hand1 if the filler-rod is too small1 it will burn up before the work is at the fusion point1 or in other words1 the work will still be too cold when the rod is melted4 7#hg7 ,there are many different methods of executing a steel weld1 and it has been noted that very few experienced welders handle their steel in the same manner4 ,most of these methods are very difficult to learn and can be perfected only after years of practice4 ,however1 a simple method which will produce results is thought the most advisable for the beginner4 ,a careful examination and study of this point has brought out the following method1 which is very easily picked up and which dispenses with most of the torch movements that are generally advocated by the old time welders4 ,illustration3 ,,fig4 #eg4--,preparing and ,heating ,steel before ,welding4 7#hh7 ,when welding two pieces of steel bars1 the cross-section of which will measure one-half inch by three inches1 they are beveled off and prepared in the manner illustrated in ,fig4 #eg1 either by means of a chisel1 file1 or by the use of a grinding wheel4 ,about an eighth of an inch of the original stock is left on the bottom side and the angle formed from these two places when brought together1 should be #ij degrees4 ,when the pieces have been prepared and placed in the position shown in the illustration1 the neutral flame is then brought down at right angles to the plane of the metal1 so that the end of the cone will just lick the surface4 ,it is moved up and down upon each side of the part to be welded until each piece is brought to a red heat1 for a distance of at least one inch back4 ,the position of the torch during this operation can be seen in ,fig4 #eg4 ,from this time on1 the operator should work as rapidly as possible1 for the quicker the fusion of the metal is brought about1 the less oxide or scale will appear and a better weld will result4 ,the description of this process may take some length but the actual fusion not nearly so long4 ,illustration3 ,,fig4 #eh4--;,in ,welding ,steel1 the ,beginner ,should ,fuse ,his ,pieces together along the ,bottom with the ,torch ,flame1 ,adding no ,new ,metal4 ,the ,metal on ,both ,sides of the ,torch ,flame is ,melted together until a ,small ,pool of ,molten ,metal ,appears1 then the ,torch is ,twisted ,smartly away1 as ,shown by the ,arrow1 and the ,metal ,allowed to 8,set0 for an ,instant before ,proceeding along the ,line of ,weld4 ,illustration3 ,,fig4 #ei4--,method of ,adding 8,filler-rod0 in ,welding ,steel4 ,note that the ,rod is ,worked behind the ,flame4 7#hi7 ,when the red-hot stage is reached1 the neutral flame is brought down to the very lowest part of the 8,v0 at the side nearest the operator and held there until the metal has melted and is about to collapse4 ,the flame is then quickly twisted away for just a second to let the metal set4 ,perhaps this operation will fuse about one-half inch or less along the bottom of the 8,v40 ,this same operation is repeated along the line of weld until the whole piece is fused along the bottom4 ,it will be noted that no filler-rod has as yet been used4 ,after the last portion has been fused1 the flame is brought back to the starting-point and played not only on the bottom1 which has already been fused1 but on the sides of the 8,v0 as well1 bringing an area of about one inch in diameter to a molten condition4 ,the tip of the welding torch is held in a vertical position all this time to introduce as much heat into the weld as possible4 ,during this operation the filler-rod1 which should measure three-sixteenths or one-quarter inch in diameter1 is picked up by the operator's free hand and its end brought near the heat of the flame so that it may be warmed and will not chill the metal when introduced into the weld4 ,when the melted metal is running freely1 the tip of the welding torch is slowly inclined in the direction of the part to be welded and is advanced along the 8,v-ed0 out portion at this angle as rapidly as the metal can be made to melt4 ,this position is shown in ,fig4 #ei4 ,it will be noted that as the flame advances along the line of the weld the molten metal will mount up behind it of its own accord1 providing the metal is in a molten condition1 when the flame passes over it4 ,during this period the filler-rod is stirred into the molten metal in a circular movement which should be in back of the torch as much as possible4 ,this means that the torch comes in contact with the filler-rod but very little and the rod is melted1 not by the flame1 but by the molten metal of the piece being welded4 ,it will be noticed at times1 when too much metal has been welded and the torch is not advancing rapidly enough1 that some of the molten metal will run ahead of the flame1 into that part of the 8,v0 yet to be fused1 and to the unwary student this will be looked upon as a safe place to add his filler-rod4 ,however1 when the piece is broken and the cross-section of the weld examined1 it will be found that in this part of the weld1 the metal has only been laid on and not fused4 ,the beginner should watch this operation and see to it that this molten metal is not permitted to run ahead of his torch1 an act which he can overcome by the proper manipulation of his filler-rod1 which really governs all the melted metal behind the flame4 ,if not enough metal has been added to fill in the 8,v0 to the proper thickness1 this operation can be repeated until enough metal has been added4 ,by practicing this method the student can be taught to execute a very successful weld and reinforce it all in one operation without any chance of burning his filler-rod or lapping his metal4 ,more practice is required to successfully weld steel than most other metals and the beginner should not be discouraged if it takes him some time to conquer this metal4 ,it should be forcibly impressed on the student that the metal must be in a molten condition before the filler-rod is added1 or else it will stick and prevent his working readily and in addition will produce a very faulty weld4 ,fusion is the thing to bear in mind for without it success cannot be expected4 ,illustration3 ,,fig4 #fj4--,this ,method of ,adding the 8,filler-rod0 when ,welding is not ,recommended for the ,beginner4 7#ij7 ,while outside appearances should not be considered as a prime requisite1 when beginning it is always well to add more metal than is really necessary in order to reinforce the weld as much as possible4 ,it cannot be expected1 however1 that a steel with the same cross-section as the original will possess the same properties and be as strong1 for a weld is only a casting unless treated otherwise and the steel or wrought iron used in the specimens is of rolled stock4 ,if too much metal has been added and dressing down is necessary1 the student will find that by using a slightly oxidizing flame the surplus metal can be burnt away very rapidly and a very good-looking job can be executed much more rapidly than if a neutral flame were used4 ,it is well to remember1 however1 that this is used only in dressing off pieces and in places where the strength of the weld is not to be jeopardized4 7#ia7 ,when advancing in steel work1 it will be noticed that the same provision for contraction and expansion is not considered in as great proportions as on cast iron1 and the reason is quite evident4 ,in cast iron we find the metal is very brittle and will not give without breaking1 whereas on steel it is more ductile and will twist and bend before breaking4 ,this does not mean1 however1 that the important points of expansion and contraction are to be neglected in steel work1 for they are very important1 as we shall see later on4 ,,part ,,two4--,,steel ,,welding 7#ib7 ,it is still supposed that the beginner knows very little about the various kinds of metals1 or methods of distinguishing between them4 ,this is of great importance and should at once be overcome1 as he will not at all times have someone over him to diagnose his case and tell him the proper procedure4 ,for instance1 were he to be given a piece of cast steel to weld1 thinking that it was cast iron1 he would use a cast-iron filler-rod in executing his weld4 ,the results of such a weld would not be very favorable1 and the same would hold true if a steel filler-rod were used on cast iron4 ,an occasional glance at the table in paragraph #fg will acquaint him with the various tests to make when deciding upon the nature of the piece to be worked upon4 ,the tests should be applied in every doubtful instance4 ,when working on cast steel1 a student may think that he must have a cast-steel filler-rod1 but this is an exception to the general rule and he can use the same style filler-rod as he would employ on ordinary steel work4 ,it might be mentioned here that when working on alloyed and high-carbon steels1 the filler-rod generally contains some of the alloy or carbon which will tend to replace that destroyed by the action of the flame in the original metal4 7#ic7 ,in welding cast steel the same procedure takes place as previously described for steel1 and it should present no real difficulties after that process is understood4 ,there may be more sand1 oxide and other impurities present on account of the nature of the metal1 but these can all be worked out if plenty of heat is applied4 ,at times1 when working in steel1 it will be found that there may be a small hole develop in the center of the weld and as the torch is worked into this hole it is found that it goes down a short distance and seemingly refuses to be worked out4 ,this is what most welders call a 8crater10 and is caused by the metal at the bottom not being hot enough for the surrounding melted metal to fuse it4 ,when found they should be removed before adding any more metal4 ,by playing the torch flame around and around it1 so that the heat may be transmitted to the bottom of the 8crater0 and it brought to the melting-point like the surrounding metal and suddenly jerking the torch away1 it will disappear4 8,craters0 are generally formed during the first part of the weld1 especially if the 8,v0 is narrow1 and they are hard to handle when deep4 ,under no circumstances should the filler-rod be melted into them in trying to make them disappear1 as this will only mean covering them over4 7#id7 ,some welders find that hard spots develop in their welds which they have difficulty in overcoming1 and it is a very serious handicap when the weld is to be machined1 for ofttimes it will break very expensive tools and leave a portion of a drill or die broken off in the metal4 ,it is probably safe to say that the principal cause of hard spots in steel welds is due to lack of heat4 ,this1 if given careful thought and consideration1 will be brought home forcibly to the welder as he proceeds in his work1 for the lapping of metals1 trapping of oxides1 8craters10 too rapid cooling1 etc41 may all be directly attributed to a lack of sufficient heat4 ,if the metal is in a molten state1 all impurities will be brought to the surface1 for they are bound to be displaced by the weight of the metal1 the same as corks in a barrel will float to the top if water is introduced4 ,the water in this case has a greater specific gravity than the corks4 ,illustration3 ,,fig4 #fa4--,the ,open ,ends on long ,steel ,welds will ,overlap as the ,welding ,progresses if ,improperly ,started4 ,illustration3 ,,fig4 #fb4--,showing how ,open ,ends of ,steel pieces are ,spread ,slightly to ,overcome ,lapping of ,ends in ,making ,weld4 7#ie7 ,in welding on sheet iron and steel1 many operators will find that they have more difficulty in executing a successful weld than on slightly heavier work4 ,this is no doubt due to the thin nature of the work and the ease with which it may be burned or carbonized if the operator is not alert4 ,when working on such material a very small filler-rod is used if thought necessary but this rod must be as free from impurities as possible4 ,when working on a long seam such as may be encountered on a steel tank1 it will be noticed that in welding from one end along the seam that the metal ahead of the flame will tend to overlap as shown in ,fig4 #fa4 ,this may be overcome by tacking 7that is1 fusing the metals together71 at various points before starting the weld1 or the parts ahead of the torch can be separated as is shown in ,fig4 #fb and held this way by using a wedge4 ,this is moved along as the weld advances and permits the edges to close together4 ,another method used by manufacturers who make a specialty of this work is to construct a jig which clamps the ends rigidly and they are welded while in this position4 ,this phenomenon in steel welding will appear rather strange to the welder who has had some experience on thin cast-iron work1 such as oven doors and the like4 ,in these he found that as his weld advanced1 the welded portion before him would separate1 and when he had welded about four inches or so it would be necessary for him to jump his flame back to the beginning of his weld and heat up that portion1 in order to close up the cracks before him previous to his continuing the work4 ,this is illustrated in ,fig4 #fc4 ,this may be explained by the fact that steel is a very ductile metal and when it is fused1 the expansion is taken care of internally by the two edges combining4 ,then1 in cooling1 the metal contracts1 an action much more rapid in steel than in cast iron1 and draws the edges of the steel plates past each other so that they overlap4 ,in cast iron1 which is rigid1 the edges are expanded by the fusion of the metal and this space is then filled up with new metal1 holding the edges apart4 ,as the weld progresses the metal ahead of the torch is pushing out1 and that behind is cooling off1 which acts as a lever on each side to open up the unwelded ends4 ,illustration3 ,,fig4 #fc4--,this ,illustration ,shows how the ,open ,ends of ,thin ,cast-iron ,pieces ,spread apart as the ,weld ,progresses4 ,to ,close the ,edges together1 ,jump the ,torch ,flame from ,b to ,a2 as ,a heats up1 ,b ,cools and the ,lever-like ,action ,closes the ,opening4 7#if7 ,to weld a broken automobile frame successfully the body of the car should be raised if necessary1 to keep it from burning and all pipes1 wires and gasoline leads protected with a covering of asbestos paper4 ,plenty of room should be allowed1 so that the welder may have easy access to the break1 and the frame should be jacked up on both sides of the break until the frame is in proper alignment4 ,then weld the crack from the outside1 working across the top1 then down the side and across the bottom1 reinforcing a little if necessary on all sides but the bottom4 ,then repeat this operation on the inside1 reinforcing at all points4 ,then take a strip of steel about one-eighth or one-quarter inch thick and six or eight inches long and as wide as the bottom of the frame4 ,this piece should be welded securely to the bottom of the frame with the former break in the middle of the strip4 ,a cut representing this job is shown in ,fig4 #fd4 ,by this method the frame can be made stronger than originally4 ,illustration3 ,,fig4 #fd4--;,a ,good ,method of ,reinforcing a ,weld on an ,automobile ,frame is ,here ,shown4 ,the ,patch as ,pictured ,here is only 8,tacked ,on40 ,it ,should be ,welded ,securely to the ,bottom of the ,frame on all ,four of its ,edges4 ,,part ,,three4--,,steel ,,welding 7#ig7 ,aside from the difficulties already mentioned in steel welding1 there are many others4 ,a few of these will be taken up in order to let the beginner know how to approach the various problems which may confront him4 ,but in no wise is this to be considered to be a treatise on advanced work4 ,ofttimes the question arises1 ,can springs be successfully welded8 ,now1 while springs have been welded1 and they have been tested out thoroughly1 yet the practice of spring welding with the oxy-acetylene flame is not to be recommended4 ,there are those who will weld leaf springs1 such as are found on automobiles1 and will apply rapid blows with the hammer1 while their weld is still in a heated condition and then plunge the spring in water or oil to harden it and the weld4 ,a close observer will readily see why this procedure is not correct4 ,springs of this nature are made up of metal which takes a uniform hardening1 and were it not so they could not be considered springs4 ,now1 if there is a fracture and a foreign metal1 which under no circumstances can be expected to take the same hardening as the rest of the spring1 is introduced into the weld1 it can easily be seen why a fusion of this kind is not to be relied upon4 ,if it were possible to diagnose or take an analysis of the metal in the spring and use a filler-rod which1 after being acted upon by the flame1 would come out the same as the metal in the spring1 then some success might be expected1 but until that time1 welding of springs will not be encouraged4 ,unless perchance the break is of such a nature that it can be reinforced readily and is in such a position that a resilient quality is not necessary4 ,illustration3 ,,fig4 #fe4--;,building ,up ,worn ,shafts4 7#ih7 ,work on crank-shafts often causes perplexity on the part of the beginner1 for he usually hears this matter discussed pro and con4 ,crank-shafts of four inches in diameter can be successfully welded with the oxy-acetylene flame1 and even larger1 if correct methods are employed4 ,there are many points which the welder considers before deciding whether a weld of this nature is advisable4 ,of course the usability of the piece after it has been welded is the main issue when executing any kind of a repair job4 ,now1 a crank-shaft will generally break in either of two ways2 by some external force1 such as a connecting rod breaking loose1 or by crystallization1 which is usually due to fatigue4 ,now1 in the latter case1 ofttimes the shaft will break in the cheek of the 8offset10 and possibly no part of the shaft is thrown out of alignment4 ,when such is the case1 welding is usually recommended and the shaft may be brought back to a useful state in very quick order4 ,however1 in the former case1 the shaft is apt to be sprung1 and while it could be welded1 the machine work necessary to restore it to normal requires much time1 and it has been known1 where after spending a matter of days in trying to get proper alignments1 work was scrapped as useless4 ,so it is entirely up to the welder in work of this kind to determine whether the job is worth while or not4 ,there are certain parts of a crank-shaft upon which welding work can be done with a marked degree of success1 such as building up worn bearings and the like4 ,in doing work of this kind it is recommended that the welder fuse his metal in a line parallel to the center line of the bearing1 seeing to it that he has a perfect fusion between the surface of the bearing and the metal he is fusing and adding plenty of metal1 to insure enough being used1 so that no low spots will show up when it is machined4 ,it is considered that by adding the metal as suggested the welder will hold his heat much better than if he attempted revolving the shaft continually4 ,fig4 #fe will show the method here outlined in a very clear way4 ,illustration3 ,,fig4 #ff4--,shaft ,broken at ,end of ,square ,shank1 its ,weakest ,point4 ,illustration3 ,,fig4 #fg4--;,broken ,part of ,shaft ,removed and ,new ,piece ,added1 thereby ,moving the ,weld away from the ,weak ,part4 7#ii7 ,when working on shafts the welder will encounter such articles as automobile propeller shafts and rear axles1 which generally break adjoining the square ends4 ,he will no doubt wonder whether it is advisable to weld this square end back on1 or whether to try and build up the shaft the desired length4 ,undoubtedly the point of fracture is the weakest portion of the entire shaft1 else it would not break there4 ,the execution of a weld at this point where no additional metal can be added or any means of reinforcing used is not to be recommended4 ,fig4 #ff will show the problem which confronts the welder1 and ,fig4 #fg the suggested means of overcoming the difficulty4 ,by removing about four inches from the broken end of the shaft and adding a new piece1 about ten inches long1 of the same diameter1 the weld will be removed from the weak point2 a heavier weld can be made1 and the end can be machined off to the desired size4 ,this procedure is recommended on all jobs of like nature4 7#ajj7 ,occasionally case-hardened ring gears are brought to the welder to have teeth built up or new ones added1 and although the welder must realize that the hardening is destroyed by the action of the flame1 yet he does not understand why it is necessary to reharden the gear4 ,a little thought on this subject will make him appreciate the fact that if he destroys certain properties in metal which have been introduced for a reason1 these must be replaced if he would bring the job back to normal4 ,it would be like heating up a tempered lathe tool1 or cold chisel for that matter1 and trying to use it before it had been retempered4 ,therefore if hardening or temper is destroyed by the flame it must be restored4 ,illustration3 ,,fig4 #fh4--,when ,welding a ,small ,section to a ,larger ,one1 the ,flame of the ,torch is ,directed toward the ,heavier of the ,two4 7#aja7 ,if a weld were to break1 it would be necessary for the welder to remove all metal added in the first weld before attempting to reweld4 ,this is true of his own work as well as that of others which he may be called upon to do4 ,for no matter how good the surface may appear1 without a solid foundation no weld is of any value1 and unless he clears out all of the old metal he cannot be sure of the work4 ,this will apply not only to steel work1 but to all metals1 and it is a point which should be borne in mind4 7#ajb7 ,at times there are jobs come up in which one piece of work is to be fused to another which is much larger1 and will absorb much more heat during the weld4 ,when handling such work1 it will be necessary to play the torch upon the larger piece most of the time1 as shown in ,fig4 #fh1 in order to bring both pieces to a fusion point at the same time and keep them in that condition4 7#ajc7 ,once in a while it will be necessary for a welder to fuse cast iron to steel or vice versa1 and the question will arise as to which filler-rod he will use4 ,it has been found that a cast-iron filler-rod can be used with success and of course when using a cast-iron filler-rod1 a cast-iron flux will be necessary4 ,work of this nature is not very frequent4 ,,part ,,four4--,,steel ,,welding 7#ajd7 ,when steel is in a melted condition1 it seems to be in a very susceptible state4 ,it appears to absorb gases1 and with constant working an oxidation is in evidence which materially effects the strength of the metal4 ,when working on vanadium and other alloyed steels1 if kept in a molten condition too long1 many of their principal characteristics are destroyed4 ,for this reason it is advisable to execute steel welds just as rapidly as possible4 ,while this is true of most work1 it is especially to be emphasized on steel4 ,to assist the welder in executing welds on large steel castings1 the pieces are generally preheated1 so that the work will take less time1 be more successful1 and save both oxygen and acetylene4 ,when working on preheated jobs1 in order to get the desired angle on the filler-rod so the welder may use it without discomfort1 a light heat is played on the filler-rod1 a matter of six or eight inches from the end being fused and then bent to an angle of #ij degrees1 so that the operator may hold the rod at some distance from his work and still introduce it in the manner he desires4 ,some operators weld their cast-iron filler-rods together1 to get the desired angle as shown in ,fig4 #fi1 but this is not as common as the steel method1 probably because cast iron will not bend and it requires some time to weld the rods together in this manner4 ,illustration3 ,,fig4 #fi4--,kinks for ,handling 8,filler-rod0 on ,large ,work to ,remove ,welder's ,hand away from ,heat of ,flame4 7a7 shows how the steel 8,filler-rod0 is heated by the torch flame about #f inches from the end and bent to the angle desired4 7b7 illustrates how cast 8,filler-rods0 are handled4 ,since they will not bend1 they are welded in the ,t shape shown4 ,first one side is used in fusing1 and then the other4 7#aje7 ,in some parts of the country boiler flues are acted upon and eaten away by the impure water used1 and when high prices prevail1 retipping is generally resorted to4 ,a simple method in which they can be satisfactorily and cheaply done is as follows3 ,cut off the poor end until solid metal is reached1 with a pipe cutter1 which will tend to 8,v0 the work as it cuts and at the same time will squeeze the edge of the pipe in4 ,after cutting1 this end of the flue is placed on the horn of an anvil and the burr on the inside1 which has been made by the cutter1 is flattened out4 ,it is very important that the flue be of the same size throughout in order to permit its being cleaned4 ,it is then placed in 8,v0 blocks or a trough1 made of angle iron1 such as shown in ,fig4 #gj1 and the new end which has been prepared in much the same way is placed in the position shown in ,a in the same figure4 ,the piece is tacked on at two or more spots and then laid aside until the whole set of flues has been prepared in this manner4 ,then they are replaced in the trough and welded1 one after another1 being turned at one end by a helper1 thus allowing the welder to do continuous work4 ,care must be taken at all times that perfect fusion takes place between the flue proper and the piece being added1 yet at no time should the metal be allowed to run on the inside of the pipe4 ,more metal can be added than is really necessary and can later be dressed down on a grinding wheel to the desired size1 which must be such that replacement of the flue can be made4 ,various-sized pipes can be welded in much the same way where no reducers are obtainable1 the only change being that there must be a step made in the trough which will permit the various-sized pipes being lined up correctly4 ,jigs for the speeding up of manufactured articles which are to be welded are always being brought out by the ingenious workman and are to be encouraged whenever possible4 ,illustration3 ,,fig4 #gj4--,showing a ,simple ,way to 8,line-up0 ,flues when ,retipping4 ,b ,represents the old ,flue1 and ,a the ,new ,piece to be ,added4 ,illustration3 7,courtesy of the ,oxweld ,acetylene ,co47 ,,fig4 #ga4--,welded ,cracks between ,staybolts4 7#ajf7 ,in the repair of boilers many a feasible job has been given up as impossible by the unthinking welder4 ,cracks have been found in fire-box sheets around the staybolts which1 as soon as they are touched with the flame1 seem to run and keep running4 ,they really discourage those who are not familiar with this class of work4 ,many such welds have been executed and are apparently all right until tested1 when they give way and make the job worse than it was previously4 ,the trouble is in these instances that the welder has made no provision for contraction and while the job might appear to be successful1 yet the internal strains exerted will not show themselves at the test4 ,many boiler shops have found that the flat patch is not to be relied upon and when a crack is found between two stay-bolt holes1 such as shown in ,fig4 #gb1 a round hole is cut as shown by the dotted line4 ,a circular plate is then cut slightly larger than this hole and after being brought to a red heat1 it is bellied by the use of a hammer or a set of dies1 so that it assumes the shape of a saucer and is called by many a 8dished0 patch4 ,some idea may be had of such a patch from ,fig4 #gc4 ,illustration3 ,,fig4 #gb4--;,a ,crack between the ,staybolts in a ,boiler should be ,cut ,out as ,shown by the ,dotted ,line1 to ,prepare it for a 8,dished0 ,patch4 ,illustration3 ,,fig4 #gc4--;,a 8,dished0 ,patch4 7#ajg7 ,the patch is placed in the sheet with the concave side toward the operator and should be securely welded in place1 adding as little metal for reinforcement as possible1 but seeing to it that a perfect fusion is made between the patch and the sheet all the way through4 ,as soon as the weld is complete the torch is played upon the high part of the patch1 which is protruding1 and as the weld cools off1 sharp quick blows can be applied to the center of the patch1 which should be kept in a heated condition until it is nearly flat4 ,this will take care of any contraction that might set up and is a very good way of handling patches which do not exceed six or eight inches in diameter4 ,illustration3 ,,fig4 #gd4--;,a 8,corrugated0 ,patch4 7#ajh7 ,a 8corrugated0 patch has been brought out more recently than the 8dished0 patch1 and as its name would indicate1 it has corrugations around at least three of its sides4 ,while a 8dished0 patch is limited in its scope and cannot be applied to square holes unless the square holes be cut round1 the 8corrugated0 patch knows absolutely no limits as to size or shape4 ,while its preparation is probably more difficult1 yet its purpose is the same1 that is1 to take care of the contraction which takes place in sheets of metal where heat has been introduced4 ,to prepare a 8corrugated0 patch1 a piece of metal which is somewhat larger than the hole is taken and the corrugation is made by placing two rods on one side and somewhat separated and between them on the other side another rod4 ,with this section of the patch heated to a red heat1 a drop hammer is played upon it and a corrugation effected4 ,or an easier method is by the use of specially prepared dies1 which will turn out a patch in quick order4 ,it must be remembered that while the patch shown in ,fig4 #gd is only for a very simple job1 which is rectangular in shape1 yet 8,l0 shaped patches can be prepared and handled in the same manner4 ,when the corrugation has been introduced into the patch1 the latter is cut so that it will fit the hole1 and it is tacked in position with the bellied sides out4 ,the method used in applying a patch of this kind is to weld the uncorrugated side1 then start up the corrugated side and weld for two or three inches1 then play the torch upon the corrugation1 adjoining the part welded1 and slightly hammer to assist in the expansion of the same2 then return to the weld1 continuing it until the corrugation can again be played upon4 ,by doing this1 when finished the patch will be flat and no signs of the corrugations will be shown4 ,while many patches of this nature are in use giving the very best service1 the welder who looks upon the finished job cannot tell how it has been accomplished4 7#aji7 ,while the methods here given seem only to apply to boiler work1 they are not so restricted and can be applied to tanks and various vessels with success4 ,however1 when welding on tanks which have contained inflammable gases or gasoline the welder is cautioned to take every measure to safeguard himself1 and while it is known that much work is being done on such jobs1 it is not recommended and in fact quite the contrary4 ,it is true that there are such methods as filling the containers with water2 cleansing with live steam1 and so forth1 but the cautious man will refrain from working on these vessels even though such measures have been taken4 ,gasoline has a faculty of penetrating the pores of metallic surfaces1 and although these vessels have been emptied and have remained so a matter of a year1 the gasoline is still present to some extent1 as is evidenced by the fact that as soon as heat is applied and the molecules of the metal are expanded1 the gas is released in sufficient quantities to cause an explosion4 ,this is not in one instance only1 but in many1 so it has been thought best to discourage any welding work on vessels which have contained gasoline at any time4 ,illustration3 ,,fig4 #ge4--,working a ,vertical ,weld on ,steel1 from the ,top ,down4 7#aaj7 ,while it is possible to weld cast iron on the vertical1 by the use of carbon blocks and so forth1 the same kind of work can be accomplished on steel with much ease1 without the use of any blocks1 or materials other than the filler-rod and the welding torch4 ,there are two methods of handling vertical welds2 welding from the top down1 or starting from the bottom and working up4 ,the former seems to be condemned by those who have never tried it1 on account of the carelessness which is apt to be used on work of this kind4 ,however1 for the beginner1 it is thought advisable to teach this method1 as there are many places where it can be used advantageously4 ,the metal at the top of the seam1 such as a broken automobile frame1 or the like1 is brought to a molten state and held there1 not only by the velocity of the flame1 but also by the filler-rod1 as is shown in ,fig4 #ge4 ,with the choosing of a tip of the correct size1 the melted metal can be held under control with much ease1 after a little practice1 and it is allowed to descend as soon as the metal below it is in the proper shape for fusion4 ,the filler-rod is added continually1 for it is never lifted out of the molten metal1 merely stirred a little from side to side as it descends4 ,none of the melted metal is allowed to precede the flame1 and at all times the operator can see whether the edges to be fused are at the right heat4 ,as soon as the bottom is reached1 the weld can again be gone over if it is not thought strong enough1 and reinforced as much as desired4 ,as soon as the operator is familiar with this method1 he will find that much more speed can be developed1 less filler-rod lost and less lapping done than by building up from the bottom4 7#aaa7 ,in welding over head there is a tendency on the part of most welders to avoid the use of enough heat to bring their metal to a molten state1 for fear that it will drop upon them4 ,it must be remembered that lack of heat means poor welds and that the metal must be in a molten condition whenever the weld is to be made4 ,as soon as a little practice is given to this kind of work1 the welder will see that the melted metal can assume some proportions without dropping off1 despite its weight4 ,it has probably been noticed that on 8sweating0 water tanks drops of water accumulate on the bottom of the tank and do not fall off4 ,it is the same sort of problem in the case of melted steel4 ,the adhesion of the molecules and the surface tension are the forces that keep the metal from dropping4 ,,chapter ,,viii ,,brass ,,welding 7#aab7 ,it is difficult for the beginner to accustom himself to brass welding1 especially on large work4 ,while he has been taught to believe that brass has a much lower melting-point than iron or steel1 yet when he comes face to face with the actual problem of melting it1 he will find that it is necessary to hold his flame in contact with his piece much longer1 on brass work than on either of the other two1 before the melting point is reached4 ,this can be accounted for by the great conductivity of brass4 ,on cast iron and steel the heat was rather local1 but on brass work it is transmitted to all parts of the piece as rapidly as it is introduced1 and this absorbing process continues until practically the entire piece is near the melting point4 7#aac7 ,brass has for its base1 copper to which an alloy of zinc has been added4 ,now the most difficult part of fusing brass work1 is to add more metal from the filler-rod to the parts which are to be fused1 without burning up any more of the alloy1 than is absolutely necessary4 ,seeing that the copper and zinc have different melting points1 it is a very difficult feat and requires considerable practice4 ,much of this trouble can be eliminated by the use of a filler-rod which has the correct proportion of alloy added1 so that it may take care of and replace any that has been destroyed by the flame4 7#aad7 ,brass work is 8,v-ed0 out when welding is to be done1 in practically the same way as cast iron4 ,only under no circumstances should the ends of the parts be burned off1 when 8,v-ing10 as the heavy oxide which is deposited on the remaining metal is very hard to combat with the welding flame4 ,the ends of the work are brought to a red heat with the flame that is slightly carbonizing4 ,this is held directly in contact with the work during the preheating stages1 in much the same manner as on cast iron1 and a small layer of carbon may be seen to accumulate around the weld4 ,now1 in theory1 this would seem the worst thing possible to have present1 but in practice a small quantity of this soot acts as an aid in making the weld1 besides making the flame less intense1 which saves much of the alloy1 from being burned when the fusion occurs4 ,when the ends have become red hot1 the same procedure is used as in working steel1 except that the torch is given a slightly greater angle and a brass flux is used4 7#aae7 ,contrary to most authorities we find that an abundance of good flux is desirable on brass work and that it is almost impossible to use too much4 ,it is desirable to use only the best welding fluxes1 for the best welds are to be insured only under ideal conditions4 ,if a welder were to run short of flux1 however1 he might use powdered borax of the #bj ,mule ,team variety1 to tide him over until he could get a new supply4 ,the flux is added in the same way as the cast-iron flux1 that is1 by dipping the heated end of the filler-rod into the flux container4 ,enough will adhere1 and when added will clear up the metal in the vicinity of the weld4 ,it should be added as often as a welder notices his metal needs cleaning and this will vary depending upon whether there is a slow or rapid worker behind the torch4 ,a man must use his own judgment in cases of this kind4 ,remember that the flux is a cleaning agent and if the surface is clean1 no additional flux is necessary1 but if the contrary is true1 that is1 if the surface is full of oxide and the filler refuses to flow easily1 flux is necessary and should be added4 7#aaf7 ,during the welding1 dense white fumes will come from the fusing brass4 ,this is the burning out of the alloy1 that is1 the zinc4 ,these fumes are injurious to the welder and should be avoided1 if possible1 by proper ventilation4 ,the use of a proper filler-rod and rapid work will largely tend to overcome the presence of these fumes1 but if the operator is very slow1 they will appear1 and are followed by a porous and brittle weld1 which if broken afterwards will show a large number of blow holes4 ,the most difficult part of brass welding as a whole is to add the filler-rod1 being certain of a fusion1 without burning out the zinc4 ,when brass is in a heated condition1 it is very fragile and will crack readily if disturbed4 ,all precautions should be taken to see that no sudden jarring is given the piece until the weld has completely set4 ,when this work is done many welders plunge their work in water1 in an effort to make it more ductile and easier to machine4 ,while this1 of course1 is condemned by theorists and rightly so1 in practice there seems to be no injury results4 ,,chapter ,,ix ,,part ,,one4--,,aluminum ,,welding 7#aag7 ,so far as the actual fusion of aluminum is concerned1 it is probably more easily learned than any other metal1 but on account of the rapid conductivity of heat and the loss of most of its strength when heated1 aluminum has caused much concern among oxy-acetylene welders4 7#aah7 ,there are two methods used in welding aluminum1 the flux method and the puddle method4 ,the puddle system gets its name from the use of a puddle stick or spoon-like rod which is used to stir the metal together1 and is very satisfactorily used on all cast aluminum4 ,the flux method is applied to both cast and sheet aluminum and it is so-called because a flux is used to break up the oxide along the line of weld4 ,the discussion to follow applies only to cast aluminum4 ,it is in this metal that most interest is centered1 as the welding of sheet aluminum1 such as is found in automobile bodies and some cooking utensils1 is not encountered in the ordinary run of work4 ,illustration3 7,courtesy of the ,torchweld ,equipment ,co47 ,,fig4 #gf4--,showing ,aluminum ,crank ,cases ,before and ,after ,welding4 7#aai7 ,when working with the flux method about the same sized tip is used as when working on cast iron4 ,this is applied to the line of weld and held there until the oxide on the surface commences to wrinkle and small globules of a mercury-like appearance form on the surface4 ,when heat is introduced in aluminum it is transmitted throughout the piece in the same manner as occurs in copper and brass1 therefore it will require much more time to heat the work than the same sized piece of cast iron or steel4 ,as soon as the weld assumes the condition mentioned1 fast work is necessary or the metal will collapse1 for it loses most of its strength when heated to this condition4 ,the end of the filler-rod bearing the flux is brought down on the metal and immediately the surfaces will clear up and run together1 like so much mercury4 ,the torch is instantly jerked away and applied farther along the weld4 ,the theory of this reaction is that the heavy aluminum oxide is the only thing which prevents the metal flowing together when heated1 and as soon as the flux is introduced this oxide will be destroyed along the line of weld and a fusion of the metal effected4 ,this actually takes place1 providing enough heat has been introduced to permit this reaction to penetrate the depth of the weld4 ,the flux contains the chemicals necessary to cause this reaction if the metal is in the right condition4 ,there are many welders who do not use sufficient heat and blame the faulty results upon the flux4 ,on the other hand1 there are many fluxes which are absolutely useless in performing a function of this kind4 ,the chemicals necessary in compounding a good flux for this class of work are expensive and therefore this flux cannot be procured at a low price4 ,when the weld is finished and cooled the surface should be scrubbed with soap and water to remove all traces of the flux1 otherwise a corrosion may occur a month or so afterwards1 and while it may not affect the weld in any degree1 the owner of the piece may not be pleased at the sight4 ,it is therefore advisable to remove all traces of flux used on aluminum work4 7#abj7 ,the puddle system differs from that of the flux1 insomuch that when the metal has been brought to the same heat1 where the flux has been applied it will be found that the metal is really in a pasty condition4 ,it can be stirred together and the break entirely eliminated by the use of a puddle stick1 either of a pointed or a flat spoon-shape design1 as shown in ,fig4 #gg4 ,during this puddling stage1 the torch is usually held in the left hand with the flame some distance away from the work1 only introducing enough heat to keep the puddle pasty4 ,the puddle stick is handled by the right hand and when extra metal is needed the puddle stick is laid aside and the aluminum filler-rod is picked up and worked into the weld4 ,when sufficient metal has been added the puddle stick again comes into play and can be used in stirring the metal together and finishing it off in the desired manner4 ,reinforcing the weld will apply to aluminum the same as every other metal1 and a very neat job can be made after a little practice with the puddle stick4 ,at times some of the aluminum may adhere to the stick1 which is made from a quarter-inch piece of steel filler-rod1 but this can be removed by scraping it upon the fire bricks which should be in the vicinity of the weld4 ,illustration3 ,,fig4 #gg4--8,puddle-sticks0 for ,welding ,aluminum4 7#aba7 ,there are two kinds of filler-rods used in aluminum welding4 ,both are aluminum1 but one is cast and the other is a drawn rod4 ,this same difference will also be noticed in bronze filler-rods1 and there has been much discussion as to which is the desirable one to use4 ,neither of them is supposed to be #ajj per cent pure aluminum1 as such a filler-rod does not give the desired results under the action of the flame4 ,a matter of from #ij to #ie per cent aluminum1 with #e per cent to #aj per cent of copper present as an alloy1 is found to make a stronger and more successful weld4 ,it is recommended1 if possible1 to use the drawn rods whenever available2 for a weld at best is only a casting1 and if this casting can be made from virgin metal1 rather than recast from metal which has been cast many times and the contents not known1 it is thought that the results will be far more satisfactory4 ,a weld made with such a filler-rod1 care being taken to work out the oxides1 will compare very favorably with the strength of the original metal and in many instances a reinforcement will make it much stronger4 7#abb7 ,to combine the two methods of welding aluminum is not recommended4 ,if the flux were stirred up inside the weld with a puddle stick an unsatisfactory weld would result1 so they are to be kept entirely separate4 ,it is not necessary to 8,v0 out aluminum for the same reason as other metals are 8,v-ed0 out4 ,when it is in workable condition it can be puddled and stirred about as desired4 ,it is well1 however1 to 8,v0 out slightly for the sake of marking the line of weld4 ,when aluminum is heated up1 the expansion which occurs may close up the crack1 which was previously quite visible1 in such a manner that it cannot be located without much loss of time4 ,ordinary chalk or soapstone1 if available1 may be used to mark any preheated work1 but the use of a chisel along the line of weld is the most reliable method4 ,,part ,,two4--,,aluminum ,,welding 7#abc7 ,it will be noticed1 when welding aluminum1 that bright surfaces will oxidize immediately when exposed to the air4 ,this action occurs perhaps faster on aluminum than on any other metal4 ,with this oxide or scale present the metal will not run together nor fuse1 no matter how much heat is applied4 ,the metal may be molten on each side of an oxidized crack and at times will cause the line of fracture to even float1 but if the oxide is not destroyed the metal will not fuse4 ,as has been noted previously1 two methods are used to destroy this oxide1 namely1 the flux method and the puddle system4 ,on account of this exceedingly rapid oxidation1 it will be found to the operator's advantage to complete his aluminum welds as quickly as possible in order that he will have less of this oxide to combat4 ,it will be found in using the puddle system that greater haste can be made by using the torch in the left hand1 leaving the right free to do the puddling and to add whatever metal is necessary4 ,in this method most of the success depends upon the operator's skill in handling his puddle stick and puddling in additional metal4 ,generally the right hand can do this more rapidly than the left4 7#abd7 ,it is well to learn how to make a successful weld from one side of the metal only1 and while this will apply to all metals1 it is especially advantageous in working aluminum4 ,where a small layer of metal has been added to one side of an aluminum job1 such as a crank case1 and it does not penetrate the entire thickness of the metal1 when the other side is turned1 and the flame applied to it1 a difference in temperature and the loss of strength in this metal when heated will cause the first side welded to crack unless the operator is extremely cautious4 ,therefore it is always well to learn how to penetrate the entire thickness of the metal from one side and make a satisfactory weld in this manner4 7#abe7 ,as previously stated1 aluminum when melted loses most of its strength1 and if not supported by some means or other the metal will collapse4 ,on account of this it is advisable to back up aluminum work1 when possible1 whether the job is to be done cold or in preheated condition4 ,the most successful manner of backing up is shown in ,fig4 #gh1 wherein ,a represents a thin sheet of copper which has been fitted to the work1 and daubs of asbestos cement shown at ,b will aid to some extent in holding the plate in position1 but this alone should not be depended upon4 ,a prop or fire brick1 upon the top of which has been placed a cushion of cement1 will serve as a good backing1 but where this cannot be accomplished filler-rods may be bent in the manner shown in ,fig4 #gh4 ,these filler-rods are not of the springy type1 but are of soft wire and the loop as shown is not for a spring effect1 but merely to take care of the contraction and expansion of the wire4 ,copper is given a preference over most of the other sheet metals1 because it can be peened with a hammer to any shape desired1 and many odd shaped additions can be formed by its use4 ,illustration3 ,,fig4 #gh4--,one ,method ,used to 8,back ,up0 ,aluminum ,work1 when ,welding4 ,a ,represents a ,sheet of ,copper2 ,b1 ,asbestos ,cement4 7#abf7 ,the use of clamps1 when working on aluminum1 is not recommended on account of the great conductivity of heat and the weakening of the metal as it approaches the melting-point4 ,pressure of any kind is not desired and the operators who attempt to use clamps will regret it sooner or later4 7#abg7 ,in aluminum work contraction and expansion take place the same as in other metals1 only to a much greater extent1 and greater allowances must be made4 ,however1 the same rules can be applied when determining whether work should be preheated or not1 for if the ends are free to move1 the work can usually be accomplished without preheating1 whereas if confined1 it will be necessary4 ,when preheating is necessary the whole piece must be treated in the same way1 regardless of the size4 ,if only part of the work were preheated and the balance left exposed1 it would be almost impossible to avoid warpage and shrinkage strains1 which would render the work useless4 ,always preheat the entire piece if any portion requires it4 7#abh7 ,great care must be exercised when setting up aluminum work for preheating4 ,its weight should be distributed equally on whatever support is used1 so that there will be no danger of any one part sagging1 thereby throwing the whole piece out of alignment4 ,a good way of accomplishing this is to lay fire bricks on their flat side1 in such a manner that the weight of the work will be fairly well distributed4 ,then put a daub of clay or asbestos cement on each brick and press the aluminum piece down on this cushion4 ,this will overcome the use of shims and other methods used for jacking up the work1 which are unreliable4 7#abi7 ,if charcoal is to be used as a preheating fuel1 an oven of fire brick should be built up with draft holes in the bottom layer of brick1 as described in the chapter on ,preheating4 ,a layer or two of charcoal is then ignited4 ,the oven is then covered with asbestos paper or a piece of sheet metal4 ,asbestos paper is preferable as the metal becomes very hot and is apt to burn the operator4 ,after the fire has received a good start1 additional charcoal is added until sufficient heat is obtained4 ,this can be determined by sprinkling a little sawdust on the surface of the aluminum1 and if it chars readily1 the work is ready to weld4 ,other methods have been outlined previously1 any or all of which may be used in learning this heat4 ,in executing the weld as little of the work is exposed to the air as possible1 in order to hold a uniform heat and not permit any part to become chilled4 ,at the completion of the weld the oven is covered over1 the openings in the bottom row of bricks are stopped up1 and the piece allowed to cool with the dying fire4 ,the charcoal process is the slow but sure method of handling preheated aluminum work1 and is always recommended4 7#acj7 ,when preheating aluminum with torches burning kerosene or gas a different kind of oven is built1 as previously described in the lecture on ,preheating4 ,no openings are left in the lower row of bricks and the oven is built very much closer to the work being preheated4 ,as the object is to confine as much heat as possible and have a uniform temperature throughout1 it is not desirable to have such ovens loosely constructed4 ,if the bricks are irregular1 a double wall can be built with a layer of asbestos between them4 ,such a procedure is always recommended if time and bricks permit4 ,a hole is left in one end of the oven for the preheating torch flame to enter4 ,on aluminum work the flame is never played directly upon the metal4 ,a baffling plate of metal or fire brick is used to distribute the flame around the sides of the piece and very satisfactory results may be obtained by preheating in this manner4 ,,part ,,three4--,,aluminum ,,welding 7#aca7 ,many times aluminum crank cases which have large holes punched in them and parts missing are brought to a welder for repairs4 ,a question arises as to whether it is best to back up these holes and fill in the missing parts with a filler-rod as the welding progresses1 or whether these parts should be cast separately or cut out of another crank case4 ,it will generally depend upon the size of the hole1 as to the desirable procedure in a case of this kind4 ,it must be remembered that if the casting and welding are to be done at one and the same time each additional layer of metal must be fused to the last layer and that in reality a great deal of welding is necessary4 ,in addition this added metal must be fused to the crank case4 ,on small holes1 perhaps two or three inches in diameter1 this method is recommended1 but if the hole is much larger1 it is best to cast a piece and then weld it in1 for in this instance there is only one line of weld to look after4 7#acb7 ,on aluminum work it is proper to weld from the closed end of a crack toward the open1 whether the piece has or has not been preheated4 ,this is true also of all other metals1 for if the weld were to be started at the open end and worked backwards there would certainly be internal strains set up1 which would be undesirable4 ,if it is not clear which end is the open one1 the operator should stop a moment and figure it out4 7#acc7 ,were a suspension arm of the ,u type on an aluminum crank case to break about three or four inches from the body of the case1 it could be welded in place without dismantling the motor1 if handled properly4 ,free access must be had to the line of break1 so that the operator can manipulate his flame at whatever angle he thinks best4 ,due to the contraction and expansion1 which may throw the piece being welded out of alignment slightly1 it is best to blank the bolt hole at the end of this suspension arm and face it off1 before the piece is welded in position4 ,later a new hole can be drilled which will line up accurately with the frame1 and the welder will not then have to worry or attempt to return it exactly to its former position4 ,in order to keep the case itself as cool as possible1 wet asbestos should be packed around it1 near the broken arm1 so that too much heat will not be absorbed by it4 ,the broken end is then tacked in position at two or three places and the weld started4 ,on such a problem the puddle system will be found best1 for both horizontal and vertical welding are to be done1 as well as some overhead4 ,as flux causes the metal to flow1 it is rather difficult for the beginner to apply it to vertical and overhead work4 ,the puddle stick should work through the metal its full thickness and eliminate every possible trace of the break1 digging out the old metal where dirt is found1 and adding new metal for reinforcing4 ,when one side has been welded and reinforced it should not be allowed to cool while the other side is being worked4 ,the torch should be played upon it every now and then1 in order that the whole line of weld will be at approximately the same temperature2 otherwise1 the weld may break in cooling4 ,the ease with which aluminum is puddled together1 which many welders have likened to the children's method of making mud pies1 seems so simple to the beginner that he cannot see where the strength comes from when cooled4 ,on account of this1 he invariably works his aluminum too long4 ,after welding a few test bars of this metal and breaking them in the line of weld1 many old welders will gain confidence upon seeing the results of their own efforts4 ,,chapter ,x ,,welding ,,of ,,malleable ,,iron 7#acd7 ,the welding of malleable iron1 so far as the actual fusion of the metal is concerned1 is not practiced except in very few instances1 where the parts are very thin and have been completely annealed4 ,this is on account of its being what might be termed a heat-treated metal4 ,to begin with1 malleable iron is cast iron1 and becomes malleable only after it has been heated to the proper condition in the presence of material which will absorb much of its carbon content1 and kept in this state until a suitable depth of its exterior has been annealed4 ,it has been changed from a brittle casting to one which will bend to some extent without breaking1 and its surface1 by the withdrawal of the carbon1 has been converted into steel4 ,the interior remains cast iron4 ,the depth of penetration will depend entirely upon the number of hours the work is treated4 ,usually it runs from one-sixty-fourth to one-eighth of an inch1 depending upon the type of work4 ,an idea may be gained of how a cross-section of this metal will appear1 by noting ,fig4 #gi4 ,illustration3 ,,fig4 #gi4--;,illustrating ,cross-section of ,malleable ,iron4 7#ace7 ,a machinist would not think of destroying the temper in his tools and then attempting to use them without retempering them4 ,so the welder will not attempt to melt malleable iron1 for he realizes that if he were to attempt fusing this metal that its character would be entirely destroyed4 ,if he should make a fusion1 the weld itself and in the vicinity thereof the metal would be very brittle and retain none of its ductile qualities4 ,when a weld of this kind is attempted1 first1 a few steel sparks are given off from the surface of the metal1 which quickly diminish and the surface seems to recede from the flame4 ,a white foam appears as the steel surface is burned and many small blow holes then make their appearance4 ,the casting resembles a steel casting which contains much sand and impurities4 ,the welding of malleable iron1 in its broadest sense1 is therefore not recommended1 although as it has been stated there are occasions when it can be successfully accomplished4 ,the best manner of bonding malleable iron is by the use of a bronze filler-rod1 and this process will hereafter be referred to1 for convenience1 as welding1 although it may resemble brazing in some respects4 7#acf7 ,the art of welding malleable iron with bronze is not very difficult to learn4 ,possibly1 the greatest trouble will be experienced by the beginner in distinguishing malleable iron from other castings4 ,by again referring to ,fig4 #dc and carefully noting the various methods outlined1 this trouble should be overcome4 ,many times1 too1 if the welder has had any mechanical experience1 he can probably determine where the casting has been used and can ofttimes satisfy himself whether it is malleable or not4 ,malleable castings are very seldom used as a wearing surface1 and are generally employed where there is strain1 to replace steel castings and forgings1 which are much more expensive4 ,if it has been determined that the metal is malleable iron1 half the battle has been won4 7#acg7 ,in preparing malleable iron1 a clean surface is necessary in the vicinity of the weld4 ,no 8,v-ing0 out is necessary unless the piece is greater than one-quarter inch in thickness1 and then the surface of the 8,v0 should be as rough as possible4 ,the ends are placed as close together as possible1 the same as in brazing1 and a welding tip which is one size smaller than would be used on the same thickness of cast iron is then used1 with a slightly carbonizing flame4 ,see ,fig4 #bc4 ,the work is heated1 the same as in cast iron and steel4 ,this flame is played directly on the work in a vertical position1 similar to that used in preheating the weld in cast iron and steel1 until heated to a cherry red1 back about one-half inch on each side of the weld4 ,as soon as this heat is obtained1 the bronze filler-rod carries a quantity of bronze flux to the weld and this further tends to clean the surface4 ,with the end of the filler-rod directly in contact with the work nearest the operator1 the neutral flame melts the end of the rod1 which immediately should run over the adjoining surface and through the crack4 ,when this occurs the flame is abruptly twisted away from that portion of the weld to avoid burning the bronze4 ,this is repeated along the line of the weld until the entire surface is covered with a thin coating of bronze4 ,with this as a foundation more bronze is added1 but during this process the torch is turned so that the neutral flame will not bear down directly on the bronze1 which has already been added4 ,it should rather strike it at an angle and radiate enough heat from the side of the neutral flame to permit a fusion between the filler-rod and the bronze already added4 ,much more surface should be covered and more of a reinforcement made than in either cast iron or steel1 in order to warrant enough strength for this class of work4 7#ach7 ,a good bronze for welding purposes should work easily under the influence of the oxy-acetylene flame and have sufficient alloys present to take care of those destroyed by the action of the flame4 ,it is not thought advisable to work over welds of bronze1 for fear of making them porous1 unless more filler-rod is added whenever the flame is brought in contact with the weld4 7#aci7 ,welds of malleable iron can be made which will be even stronger than the surrounding metal1 and at times they can be reinforced by adding small strips of steel4 ,these can be entirely covered1 to make them inconspicuous4 ,contrary to custom it is recommended that plenty of flux be used1 for best results have been found when a surplus rather than a sparing amount has been employed4 7#adj7 ,the matter of heat in malleable iron is of considerable importance4 ,if not enough heat is used there will be no fusion between the bronze and the iron1 whereas on the other hand1 if too much heat is used1 the bronze will not adhere1 but will seem to boil on the surface and form in small globules rather than spread over the whole metal4 ,in addition the character of the piece being worked on will be changed when heated too much4 ,this matter of heat should be given great attention and the beginner should learn and have emphasized the fact that the proper heat is one which will permit the bronze to run like water over the surface1 and this will form a good foundation to work upon4 7#ada7 ,in general1 malleable iron work is seldom preheated1 for this is not necessary if the pieces have been fitted together as closely as possible before the weld is started4 ,once the student has learned the flow of metal and how to reinforce his weld1 he will be in a position to handle most any kind of malleable iron properly4 ,it is well to remember1 however1 that malleable iron is allowed to cool slowly and is not immersed in water1 as has been suggested when working on brass1 for here we have one metal in the piece itself and another in the weld1 and too great a strain would set up if they were cooled abruptly4 ,,chapter ,,xi ,,oxy-,,acetylene ,,cutting 7#adb7 ,by heating a bar of wrought iron or steel to a welding heat and holding it in a stream of compressed air1 or a strong blast1 it will at once begin to melt and sizzle1 emitting an incandescent and scintillating light4 ,this light is dangerous to observe at close range without colored glasses4 ,the burning of the metal can be maintained for hours1 without any other source of heat except that caused by the combustion of the iron4 ,the oxy-acetylene cutting process is based upon this principle1 in that a neutral flame is applied in order to heat the part being cut to the desired temperature4 ,once the melting-point is reached1 pure oxygen under pressure is applied to maintain oxidation and force out the burned portion4 7#adc7 ,the apparatus used for cutting does not differ to any great extent from that of the welding class1 except that a different torch is employed4 ,there are combination regulators and torches manufactured1 but a combination tool is always regarded by most authorities as a loss in efficiency1 either on one side or another4 ,while a low-pressure welding regulator may be used on the oxygen line for cutting1 yet its use upon large work1 where the pressure is high and the regulator must pass a great deal of gas very freely without freezing up1 this low-pressure regulator will be a serious handicap and cause much trouble1 if used4 ,illustration3 ,,fig4 #hj4--,the ,cutting ,torch ,eats its ,way through ,steel of any ,size with ,remarkable ,ease1 ,leaving a ,clean-cut ,edge4 ,this ,view ,shows a ,cutting ,torch in ,operation at the ,ordnance ,welding ,school1 ,u4 ,s4 ,army4 7#add7 ,an ideal arrangement on the oxygen line for cutting is to have a double or 8twin0 regulator attached to the oxygen drum1 one side of which will do for welding and the other1 being high-pressure type1 will produce a constant flow of high-pressure gas1 suitable for the cutting jet4 ,then when cutting is done a three-hose torch should be employed4 ,one of its oxygen connections which governs the neutral flame can be connected to the low-pressure regulator1 while the oxygen jet should be controlled by the high-pressure regulator1 the third connection will furnish the acetylene gas for the preheating flame4 ,however1 in place of this three-hose arrangement1 most cutting is accomplished by means of a two-hose apparatus1 wherein only one hose is used to convey the oxygen from a single regulator to the torch4 ,on such apparatus much trouble is usually experienced in cutting old metals where a great deal of scale is present or in a close place where the torch is apt to get hot4 7#ade7 ,many times part of the scale or metal will pop up against the tip and cause the oxygen jet to flicker4 ,this slight variation may cause an excessive pressure of oxygen to be introduced into the preheating flame momentarily1 by backing up the oxygen in the cutting jet4 ,this lean mixture of gas will generally flash back instantaneously and will deposit a layer of carbon on the inside of the tip1 which causes much annoyance to the operator4 ,this condition is to be found where there is but one oxygen line4 ,in the two-hose arrangement this is entirely overcome1 due to the independence of the pressure on each line4 7#adf7 ,the high-pressure regulator differs from the low-pressure regulator in these respects3 ,the diaphragm1 see ,fig4 #af1 is much smaller in diameter1 which makes it less sensitive1 and of course much stronger4 ,the diaphragm springs are usually much heavier2 the nozzle contains a larger opening for passing gas freely without freezing2 and to take care of the increased pressure on the line1 usually a higher pressure working gauge is added to the regulator4 ,such a regulator is capable of passing much more gas than the low-pressure type1 but as far as being as sensitive and maintaining a constant1 absolute flow of gas1 its design will not permit it to do so4 ,in cutting1 these requisites are not necessary4 ,in welding1 however1 the delicate adjustment of the flame demands a very sensitive regulator and usually the larger the diameter of the diaphragm the more sensitive the adjustment4 ,illustration3 ,,fig4 #ha4--;,end ,views of ,cutting ,tips1 ,showing ,possible ,arrangements of ,preheating ,flames in ,regard to ,oxygen ,jet4 ,the ,black ,circles ,represent the ,preheating ,flames1 which ,vary in ,number and ,arrangement ,according to the ,nature of the ,work1 the ,possible ,limit being a ,continuous ,circle1 as ,shown4 ,the ,white ,circles ,illustrates the ,oxygen ,jet1 which1 too1 ,varies in ,size ,according to the ,work4 7#adg7 ,the cutting torch differs from the welding torch in many respects4 ,the tip itself1 when looking at its end1 may resemble any one of the views shown in ,fig4 #ha4 ,in the welding torch1 but one hole is to be found in the tip2 in the cutting tips1 two or more holes are to be found4 ,in all cases the center hole passes pure oxygen1 whereas in the surrounding holes1 both oxygen and acetylene mix and when lighted give a neutral flame4 ,this will hereafter be called the preheating flame4 ,the gases issuing from these openings are controlled by three valves1 one of which may have a trigger or lever arrangement for quick action1 and it will control the center jet of oxygen which really does the cutting4 ,this is under much higher pressure than the preheating flame4 ,the other two valves will control the oxygen and acetylene gases used for the preheating flame4 ,in lighting such a torch1 the acetylene is turned on in the same manner as has been taught when welding1 until it just leaves the end of the tip4 ,then the oxygen valve is opened1 which controls the preheating flame1 and enough is permitted to pass to produce a neutral flame4 ,as soon as this has been accomplished1 the third valve should be quickly opened and held so a moment1 to see if the neutral flame has been changed4 ,generally this operation will deprive the neutral flame of some of its oxygen1 and a feather flame1 showing too much acetylene and not enough oxygen gas1 can be noticed4 ,this will necessitate turning on slightly more oxygen at the torch valve4 ,the third valve is then shut off and the torch is ready to start cutting4 ,illustration3 7,courtesy of the ,general ,welding ,equipment ,co47 ,,fig4 #hb4--;,cutting a ,heavy ,shaft4 ,illustration3 ,,fig4 #hc4--,position to ,hold ,torch in when ,cutting ,metal4 7#adh7 ,on small cutting jobs1 about as much acetylene pressure is used on the line as there would be if it were a welding job4 ,the oxygen pressure1 however1 is generally much greater1 and a pressure anywhere from ten to two hundred pounds should be used1 depending upon the thickness of the metal and the conditions which must be met4 ,in extreme cases where very heavy cuts are to be made1 a much higher pressure than has been mentioned should be used1 but the limitations given will cover a wide range of work4 ,to start a cut it is necessary to bring the preheating flame in contact with one edge of the metal to be cut and play it there until the metal is red hot4 ,as soon as this condition is reached the torch is held steady--the neutral flame just touching the metal2 then the third valve controlling the cutting jet of oxygen is opened4 ,this oxygen1 under high pressure1 quickly acts upon the hot metal and severs it instantaneously1 melting and oxidizing the metal so that it will not flow together1 in one and the same operation4 ,as soon as this occurs the torch should be advanced as rapidly as possible in the direction the metal is to be cut4 ,the more rapid the advancement and the steadier the torch is held the cleaner the cut will be2 and incidentally1 less gas consumed in the execution of the job4 ,in cutting1 as in welding1 it is always well to give the torch a chance1 and when the operator sees much molten metal splashing directly back on the torch1 he should change the angle slightly to avoid his apparatus becoming overheated4 ,it has been found that if the cutting torch is held at the angle shown in ,fig4 #hc1 the most satisfactory results can be expected4 7#adi7 ,at the present time only such metals as steel and wrought iron can be successfully cut4 ,when it comes to cast iron no method has yet been discovered to cut it with any degree of success by the oxy-acetylene flame1 on account of the high melting-point of the oxide and various other matters4 ,the day is looked forward to1 however1 when after sufficient time and study has been devoted to this subject1 that cast iron can be as successfully cut as any other metal1 by introducing another gas or agent to destroy some of the reactions which retard its application at the present time4 7#aej7 ,the use of the cutting torch in preparing steel work1 for welding of large size1 plays an important part1 in quickly and efficiently 8,v-ing0 out and getting it ready for use4 ,care should be taken1 after its use1 to see that the heavy oxide which it leaves is largely destroyed1 before any more metal is added4 ,illustration3 ,,fig4 #hd4--,method of ,cutting with ,two ,welding ,torches4 ,torch ,a is ,adjusted so that a ,neutral ,flame will do the ,preheating1 while a ,fork in the ,oxygen ,line ,supplies ,oxygen only to ,torch ,b1 and it does the ,cutting4 7#aea7 ,frequently the welder has a call for a cutting torch1 where none is available1 yet an extra welding torch or two may be on hand4 ,if this is the case1 two welding torches may be fastened together in such a manner that a temporary job of cutting may be handled4 ,the arrangement shown in ,fig4 #hd illustrates this point4 ,if no extra welding torch is available1 a carbon burning torch or any piece of copper tubing which has a valve in one end1 suitable for taking a hose connection1 and the other end free to have a welding tip brazed on1 can be used in the same manner4 ,the welding torch will give the neutral flame and the extra line of oxygen will do the cutting4 ,it is well to remember that oxygen1 no matter under what pressure1 cannot be expected to act upon cold metal4 ,a red heat is absolutely necessary4 ,there are various short cuts1 it is true1 in obtaining this heat1 and where a large shaft is to be cut1 the operator would not think of playing his torch upon such a piece of metal until it was red hot in the locality in which he wished to start his cut4 ,this would consume too much time and gas4 ,generally a hammer and cold chisel are brought into play and a slight curl on the metal is obtained as shown in ,fig4 #he4 ,the moment this becomes red hot1 the oxygen jet may be turned on1 and the cut commenced4 ,as soon as started1 the operator is able to 8carry-on0 at will4 ,illustration3 ,,fig4 #he4--,when no ,edge is ,available to ,start the ,cut on ,large ,work1 ,much ,time may be ,saved by ,making a ,curl with a ,cold ,chisel1 as ,shown4 7#aeb7 ,an armored hose is generally used on the oxygen line for cutting1 as well as on the acetylene line1 as there is much more pressure used in cutting than in welding4 ,this type of hose wears much longer and does not kink to the extent that the unprotected hose does4 ,the armor protects both lines from being burned by the melted metal1 which is very apt to come in contact with the rubber1 were it not protected in some manner4 7#aec7 ,the question often arises in welding circles1 as to why1 since the cutting torch contains a series of neutral flames1 it would not be just as well to use such a method in welding1 as no doubt more heat could be obtained and a greater surface handled4 ,the answer to such a question would be1 that the opportunity for oxidation is so great that successful welding could not be expected1 although if this were the last means at a welder's disposal1 he would certainly be justified in making a weld in this manner4 ,he should be very careful1 however1 to see that his extra oxygen supply is completely shut off and that there is no possible chance for that gas leaking into the weld4 7#aed7 ,to plunge a flame1 such as is used in the cutting torch1 under water and see it continue to burn while submerged1 looks quite marvelous to the average layman4 ,yet in cutting piling along water fronts this is continually being done4 ,not only does the torch stay lighted1 but it retains much of its efficiency as a cutting tool1 and some instances have been recorded where cutting has been accomplished at a depth of thirty feet under the sea4 ,it is true that the water conducts a large part of the heat away very rapidly1 but to facilitate such operations1 an air line is brought down which ejects air under the torch and clears the water away to some extent1 but this is not necessary4 ,in order to explain this phenomenon in a very simple way1 it will be stated that nothing will burn unless oxygen is present1 and the more oxygen used1 up to a certain point1 the more rapidly will the burning take place4 ,when submerging the cutting torch1 it is presumed that the flame obtains what added oxygen is necessary from the cutting jet and this together with the velocity of the flame and its hydrogen enveloping flame permits the neutral flame to continue burning4 ,,chapter ,,xii ,,carbon ,,burning 7#aee7 ,those who are familiar with gasoline engines will know that after being used for some time1 the impurities in the lubrication oil and in the gasoline1 which is continually being burned1 will form around the top of the piston and cylinder head in the motor4 ,when enough has been deposited and a few high points become overheated through long running1 there will be a metallic knock distinctly heard when an extra strain is being exerted by the motor4 ,this layer of impurities is called carbon and its presence means loss of power4 ,owing to the construction of most cylinder blocks1 it is a very difficult matter to reach this portion of the block without dismantling4 ,this requires skilled labor and means much delay4 ,a method of removing this carbon by the oxygen process has been devised1 which will save much time and trouble4 ,illustration3 ,,fig4 #hf4--,removing ,carbon from ,u4 ,s4 ,army ,truck1 by the ,oxygen ,process1 at the ,ordnance ,welding ,school4 ,illustration3 ,,fig4 #hg4--;,carbon ,burning ,apparatus4 ,the ,small ,copper ,tube ,a is ,flexible and can be ,bent in any ,shape ,desired4 7#aef7 ,to remove carbon from a gasoline engine1 first shut off the gasoline in the line and allow the engine to run until all gas has been removed from the carburetor4 ,this is merely a safety measure4 ,if a vacuum feed is used1 the vacuum tank is drained1 as it would require much time for the engine to consume this amount of gas4 ,the hood of the car is then removed and all parts of the motor on the side where the burning is to be done are covered with asbestos paper or by a heavy piece of canvas which has previously been dampened4 ,this is to keep the sparks from dropping into the apron or oily parts of the machine4 ,remove the spark plugs and see from the condition of these spark plugs whether the cylinder is dry or oily4 ,an oily cylinder will burn out much more rapidly than when dry4 ,this can be detected very easily from the condition of the spark plugs4 ,it is recommended that only the spark plugs be removed as the removal of the bonnet or any larger portion will require much more oxygen and will not produce as satisfactory results as when the oxygen is introduced through a small opening4 7#aeg7 ,place the carbon removing apparatus1 which consists of the oxygen drum1 regulator1 a length of hose and carbon burning torch1 the latter being made up principally of a shut-off valve and a long length of small copper tubing as shown at ,a in ,fig4 #hg4 ,turn on not over twenty-five pounds oxygen pressure as far as the torch1 and the apparatus is then ready to use4 ,with the torch inserted through the spark plug hole in number one cylinder1 that is1 the one nearest the radiator1 guide the rise of the piston until it is at the top of the stroke4 ,this means that both intake and exhaust valves are closed4 ,on automobiles where a self starter is used1 it will be necessary to use a crank for turning over the motor4 ,with the piston at the top of the stroke and both valves closed1 there is only a small portion of the cylinder head to be worked upon and this is the part which has the carbon deposit upon it4 ,all machined surfaces and valve seats are fully protected and will not be subjected to any exposure during the burning4 ,if the cylinder seems very dry1 a teaspoon of alcohol or kerosene may be sprayed into it through the spark plug port1 to facilitate the clearing of the carbon4 ,if the cylinder is somewhat oily1 this is not necessary4 ,a match or burning taper is then held over the hole and a stream of oxygen will carry the flame down into the cylinder and ignite the carbon4 ,as soon as this occurs1 a small cracking noise can be heard and the carbon will run around the inside of the cylinder in a heated condition4 ,the part around the valves should be cleaned off first1 before going to the inner chamber1 as this process does not seem to work very well if performed the other way4 ,a roaring noise will be in evidence and the popping of the carbon from the surface as it frees itself may frighten the operator when attempting his first job1 but there is absolutely no danger4 7#aeh7 ,it must be remembered that oxygen itself does not burn1 but merely assists the other inflammable material in burning1 therefore it is only the carbon which is contained in the cylinder that in this case does the burning4 ,as soon as this is all consumed1 there will be nothing else to burn and the sparks will die of their own accord4 ,when this occurs1 the operator will shut off his torch1 blow the cylinder out with compressed air and replace the spark plug and then proceed with the next cylinder1 which he will treat in the same manner4 ,he must be sure1 however1 that the piston in cylinder number two1 or whatever cylinder he is working on1 is moved to the top of its stroke and that both valves in that particular cylinder are closed before he starts his burning4 ,after all cylinders have been treated like number one and the spark plugs are in position1 the gasoline is turned on 7if the vacuum tank has been drained1 it is best to fill this71 and the motor started1 with the exhaust 8cut off0 open1 in order that any loose particles of carbon may be blown out4 7#aei7 ,while this process is in very common use1 and seems to be very simple1 there are many who go through the steps without obtaining satisfactory results4 ,it is considered best1 if possible1 in attempting carbon burning for the first time1 to try it on some motor which is about to be overhauled1 in order that the results may be studied so that the operator will not go blindly on1 without showing some improvement4 ,many times only the high points are burned out1 which will free the motor temporarily of some of its knocks1 but within a week or so they will become evident again4 ,he who will become proficient in learning carbon burning should apply himself and study his results4 7#afj7 ,there are those who consider carbon burning injurious to the motor on account of the high temperature flame which they think is introduced4 ,but it is ignorance as to the working principle of this process that makes them think this4 ,when it is considered that a gasoline motor depends upon a rapid succession of internal explosions for its power1 the folly of condemning a process of this nature1 where absolutely no actual flame is used1 will be seen4 ,it is only the incandescent particles of carbon flying about that give any heat at all4 ,after a cylinder has been burned or decarbonized1 the hand can be placed upon it immediately1 without any fear of being burned4 ,those motors equipped with aluminum pistons may be handled in the same way as those of cast iron1 and when properly used this method of decarbonization is very satisfactory4 7#afa7 ,many times it is asked how often carbon burning is to be recommended4 ,this will all depend upon the type of motor1 its condition1 and to some extent1 upon the lubricating oil and gasoline used1 as well as the mileage of the car4 ,if a machine is being run continually1 it may be necessary to have the carbon removed about every two months1 but conditions will tend to lengthen or shorten this time as the case may be4 ,when the knocks are in evidence1 and the loss of power is noticed1 it is time for the carbon to be removed1 and whether this is one month or two it is an error to continue running the car which is filled with carbon4 ,invariably the carbon burner is asked by his customer whether carbon burning will regrind valves2 this and many other questions can be intelligently answered and explained to the questioner's satisfaction if a careful study of the process is made4 ,illustration3 7,courtesy of the ,british ,oxygen ,co47 ,,fig4 #hh4--,photograph ,showing ,square ,piece ,cut ,out of a ,steel ,block #i ,inches ,thick4 ,illustration3 7,courtesy of the ,davis-,bournonville ,co47 ,,fig4 #hi4--,this is an ,electrically ,driven ,oxy-acetylene ,cutting ,machine for ,making ,duplicate ,cuts on ,steel from a ,drawing4 ,dies and many ,irregular ,forms may be ,produced at ,low ,cost by it4 ,illustration3 7,courtesy of the ,davis-,bournonville ,co47 ,,fig4 #ij4--,this ,shows a ,motor-driven ,oxy-acetylene ,device ,particularly ,adapted to ,cutting ,plates or ,sheets into ,round1 ,oval1 or ,irregular ,forms with either ,straight or ,beveled ,edges4 ,,conclusion 7#afb7 ,in drawing this elementary course in oxy-acetylene welding to a close1 the author wishes to again call attention to the fact that this course is merely to be considered as a foundation upon which to build4 ,an effort has been made to confine the student's line of thought exclusively to the actual welding of the various metals and an intimate knowledge of the tools necessary to accomplish this4 ,technical terms have been avoided as much as possible1 and history1 as well as the generation of the various gases1 have been considered only of secondary importance and have been purposely omitted4 ,many repetitions have been made to place emphasis upon certain points and methods4 ,it is hoped that the student who pursues this course if he has been restricted to the use of only one apparatus will realize that there are many such on the market1 each one of which may have its advantages1 but if the general rules1 as outlined1 are followed1 he will not have much difficulty or be covered with confusion if called upon to operate different makes of apparatus for the first time4 ,if he sees that there is gas pressure on his lines1 he should not hesitate1 thereby showing his ignorance of that particular type of apparatus1 rather let him turn on one valve1 and direct the stream of gas toward his nostrils4 ,he can then readily determine whether it is the fuel gas or not and knowing that oxygen will not burn he can turn his fuel gas on and proceed without showing any concern4 ,it might be said that confidence in one's self is the keynote of success1 and this is imperative to make an expert welder1 but to the man who studies the flame action on his metals and appreciates the apparatus to the fullest extent1 there is a very bright future4 ,illustration3 ,,fig4 #ia4--,quick1 ,permanent ,repairs are ,made on ,large ,supply ,trucks in the ,u4 ,s4 ,army by its ,corps of ,trained ,welders4 ,this ,view ,shows an ,individual ,welding ,unit in ,operation at the ,u4 ,s4 ,army 7,ordnance7 ,welding ,school4 ,illustration3 7,courtesy of ,ben ,k4 ,smith1 ,u4 ,s4 ,welding ,co47 ,,fig4 #ib4--,this ,cylinder did not ,require to be ,bored or have any other ,machine ,work ,performed1 but was ,placed in ,service ,directly after ,welding and has been ,serving for over ,three ,years4 7#afc7 ,the welder who desires the best results should procure the best apparatus possible to fill his requirements4 ,the cost of such is only of secondary importance1 the hazard attached to cheaply constructed apparatus and the loss of gas1 time and the execution of faulty work and the depreciation of the welder's reputation1 are matters of vital importance4 ,the supplies too1 such as filler-rods and the like1 should be obtained only from reliable welding companies who have their own shops in which they may test them4 ,it is false economy indeed1 to attempt to save a few cents on filling materials1 for many dollars' worth of time and gas may be lost on account of the failure of the metal added4 7#afd7 ,there are a few illustrations set forth herein1 to show what has been accomplished in the way of machine construction used in adapting the oxy-acetylene process to the requirements of various manufacturers4 ,these will tend to show to some extent what the future has in store for this wonderful process4 7#afe7 ,it has been rightly stated that oxy-acetylene welding is yet in its infancy4 ,the torches1 regulators and in fact all parts of the apparatus are constantly being improved4 ,the process of cutting cast iron must still be solved1 so it will again be stated that it behooves those who are interested in this work to apply themselves to the great future in store for them4 ,,glossary ,,definitions ,,of ,,terms ,,and ,,words ,,applied ,,to ,,oxy-,,acetylene ,,welding ,,and ,,cutting ,,acetone4 ,a liquid which is capable of absorbing twenty-five times its volume of acetylene gas under normal temperature and pressure4 ,employed as a solvent in the acetylene cylinder4 ,,acetylene4 ,an inflammable gas used for welding and cutting4 ,,acetylene ,,cylinder4 ,a steel tank filled with porous material and acetone1 in which acetylene gas is stored4 ,,adapter4 ,a brass fitting used to connect regulators to different cylinders4 ,,alignment4 ,state of being in line4 ,,alloy4 ,metal which is added to another metal4 ,a mixture of two or more entirely different metals4 ,,angle ,,iron4 ,a steel bar1 the cross-section of which forms an angle of #ij degrees4 ,,asbestos4 ,a fibrous material not affected by fire4 ,usually supplied in sheets or shredded4 ,,autogenous ,,welding4 ,the process of uniting two pieces of metal together by fusing without additional metal being added1 and without the aid of hammering4 ,,babbitted4 ,lined with ,babbitt metal4 ,generally found in bearings4 ,,back ,,fire4 ,the popping out of the torch flame1 due to a slight explosion of the mixed gas between the torch tip and the mixing chamber4 ,,bearing4 ,support or wearing surface for a revolving shaft4 ,,bevel4 ,to cut or form at an angle4 ,,beveled ,,edge4 ,an edge cut or formed at an angle4 ,,blowhole4 ,a hole or cavity formed by trapped gas in metal4 ,,blowpipe4 ,a torch which mixes and burns gases producing high-temperature flames4 ,the term ,,torch is given preference in oxy-acetylene welding and cutting4 ,,brazing4 ,uniting metals with brass or bronze by means of heat4 ,,brazing ,,wire4 ,a filler-rod of brass or bronze used in brazing4 ,,butt ,,joint4 ,a joint made by butting two edges together4 ,,cap4 ,a metal cover used to protect cylinder valves4 ,,carbon ,,blocks4 ,carbon in block form4 ,used to assist in building up parts that are to be added4 ,they may be ground to any shape desired4 ,,carbon ,,rods4 ,carbon in rod form4 ,employed to save holes around which the metal is melted4 ,,carbonizing ,,flame4 ,a flame with an excess of acetylene gas4 ,,contraction4 ,the shrinkage of metal due to cooling4 ,,cross-,,bar4 ,hand screw for adjusting the passage of gas through the regulator4 ,,cutting ,,jet4 ,central jet of oxygen issuing from tip of cutting torch4 ,,cutting ,,torch4 ,a torch with one or more heating jets and an oxygen jet1 used for cutting metals in the oxy-acetylene process4 ,,cylinder4 ,a tank containing gas under pressure4 ,,ductile4 ,that property which permits metal being formed or drawn into different shapes without breaking4 ,,expansion4 ,increase in size due to heating4 ,,filler-,,rod4 ,a rod or wire used to supply additional metal to the weld4 ,,fillet ,,weld4 ,a weld made in a corner4 ,,flame ,,propagation4 ,the rate at which a flame will travel4 ,,flash ,,back4 ,the burning back of the gases to the mixing chamber or possibly farther4 ,,flux4 ,chemical powder used to dissolve the oxides and clean the metal when welding4 ,,gas4 ,erroneously applied to acetylene gas alone4 ,both oxygen and acetylene are in the form of gas4 ,,gauge4 ,an instrument for measuring pressures of gases4 ,,generator4 ,a device for manufacturing gas4 ,usually specified as acetylene generator or oxygen generator4 ,,grain4 ,the arrangement of the molecules or crystals which make up a metal4 ,,horizontal ,,welding4 ,welding in a level position4 ,i-,,beam4 ,a steel bar with the cross-section of an ,i4 ,sometimes called ,,eye ,,beam4 ,,line4 ,hose or pipe carrying gas4 ,,manifold4 ,a header with outlets or branches by which several cylinders of gas may be used in batteries4 ,,monel ,,metal4 ,an alloy of copper and nickel4 ,,nipple4 ,a short piece of pipe4 ,,overhead ,,welding4 ,welding with the torch overhead4 ,,oxidation4 ,a combination with oxygen4 ,,oxide4 ,a coating or scale formed by oxygen combining with metal4 ,,oxidizing ,,flame4 ,a flame with an excess of oxygen gas4 ,,oxygen4 ,a non-inflammable gas used in oxy-acetylene welding and cutting4 ,,oxygen ,,cylinder4 ,a steel tank for storing and shipping oxygen4 ,available for commercial work in #ajj1 #bjj1 and #bej cubic-foot sizes4 ,the oxygen is compressed as free gas to #ahjj pounds pressure at #fh degrees ,fahrenheit4 ,,peening4 ,stretching the surface of cold metal by use of the hammer4 ,,penetration4 ,a thorough welding completely through the joint of the pieces or parts being fused4 ,,preheating4 ,the heating of a metal part previous to welding4 ,generally used to prevent strains or distortion from contraction and expansion2 also to save gas4 ,,pool4 ,a small body of molten metal formed by the torch flame4 ,,puddle ,,stick4 ,a steel rod flattened at one end1 used to break up oxides1 remove dirt and build up additional metal4 ,particularly helpful in welding cast aluminum4 ,,puddling4 ,the manipulation of the filler-rod or the puddle-stick in such a manner as to break up oxides1 remove dirt1 and aid in securing a good fusion of the metal4 ,,reducing ,,flame4 7,see ,carbonizing ,flame47 ,,reducing ,,valve4 7,see ,regulator47 ,,regulator4 ,a device for reducing and maintaining a uniform pressure of gas from cylinders1 generators or shop lines4 ,,scale4 ,a coating of oxide on fused iron or steel that breaks off as the metal cools4 ,,scaling ,,powder4 ,a name given flux4 ,,slag4 ,the oxidized metal and scale blown out when cutting4 ,,soldering4 ,uniting metals by fusing with a different metal which has a much lower melting-point than the pieces to be joined4 ,the use of a lead1 tin and zinc alloy is called soft soldering4 ,hard soldering is similar to brazing4 ,,tacking4 ,fusing pieces together at one or more places4 ,,tip4 ,a copper or brass nozzle for a welding or cutting torch4 ,v4 ,angle or groove between two beveled edges prepared for welding4 ,v-,,block4 ,block cut out in the shape of a ,v1 or angle iron1 used in lining up shafts4 ,,valve4 ,a device for shutting off the passage of gas4 ,,vertical ,,welding4 ,welding as applied to an upright position4 ,,welding ,,rod4 ,material used to supply additional metal to the weld4 7,see ,filler-rod47 ,,lectures ,,note4--,in order to determine whether the student is obtaining the information desired it is sometimes thought fitting to give written examinations4 ,these serve as an index as to what the student has learned and what he has not4 ,they also let the instructor know whether he is making every point clear in his training4 ,the following questions fit in with each chapter or part thereof and are merely a suggestion for the instructor who has no course of training outlined4 ,with one or two exceptions all answers to these questions may be found within the manual4 ,there are a few misleading questions purposely inserted to see if the student is thinking for himself4 ,,lecture ,,number ,,one ,subject--,,apparatus #a4 ,name the different classes into which oxy-acetylene welding apparatus may be divided and explain the principles upon which this classification depends4 #b4 ,illustrate by line sketches the various locations of the mixing chambers for the oxygen and acetylene gases in welding torches4 #c4 7a7 ,where is the logical location for the mixing chamber in welding torches employed in automobile and tractor repair work8 7b7 ,give reasons for so thinking4 #d4 ,how is the torch and the welding tips treated after repeated 8flash-backs0 have taken place8 #e4 ,describe briefly the working principles of a regulator and illustrate with a simple sketch4 #f4 ,explain the difference between high and low-pressure regulators4 #g4 7a7 ,can acetylene regulators be interchanged with oxygen regulators with perfect safety8 ,explain why4 7b7 ,how is it possible1 in majority of cases1 to distinguish in a very simple manner1 between oxygen and acetylene regulators1 when no gauges are attached8 7c7 ,why does this difference exist8 #h4 7a7 ,why should all tension upon diaphragm springs be removed before admitting gas under pressure to the regulator8 7b7 ,can a regulator which has been abused in this manner be repaired8 7c7 ,what can be employed as a fitting substitute for gallilith8 #i4 ,explain why the high-pressure gauge on the acetylene regulator cannot be used as an index to the contents of the attached cylinder of gas in exactly the same manner as the oxygen high-pressure gauge4 #aj4 ,why is glycerine used as a substitute for oil when regrinding torch valve-seats with emery powder1 and with lead-oxide in the caulking of leaky joints along the line8 ,,lecture ,,number ,,two ,subject--,,operation #a4 7a7 ,under what pressure is oxygen gas received in the cylinders used commercially8 7b7 ,does this pressure vary to any great extent with changes in temperature8 #b4 7a7 ,under what pressure is acetylene gas received in the cylinders used commercially8 7b7 ,does this pressure vary to any great extent with changes in temperature8 #c4 7a7 ,in setting-up apparatus for the first time1 or in attaching regulators to new cylinders1 what precaution should be observed regarding cross-bar on regulators before the gas is turned on8 7b7 ,where should the operator stand when turning on the gas8 #d4 7a7 ,how much pressure should be placed on the oxygen hose1 when the torch-valves are closed1 before starting to operate with a medium-sized tip8 7b7 ,how much pressure should be placed on the acetylene hose1 when the torch-valves are closed1 before starting to operate with a medium-sized tip8 #e4 7a7 ,after both the oxygen and acetylene gases are in the line hoses as far as the torch1 which valve on the torch is opened first in order to light8 7b7 ,what would happen if the other torch-valve were opened first8 7c7 ,what would likely occur if both valves were opened before torch was lighted8 #f4 7a7 ,how is it possible1 when lighting torch1 to determine whether enough pressure is on the acetylene line without looking at gauge8 7b7 ,how is it possible1 in the case of oxygen pressure8 #g4 7a7 ,what is meant by a neutral flame8 7b7 ,how hot is a neutral oxy-acetylene flame8 7c7 ,is the temperature of a neutral flame the same whether large or small tip is used8 #h4 7a7 ,if too much acetylene gas is used1 how will the flame be affected8 7b7 ,what action will this have on the weld8 #i4 7a7 ,if too much oxygen gas is used1 how will the flame be affected8 7b7 ,what action will this have on the weld8 #aj4 7a7 ,explain briefly how apparatus is shut-off1 when not to be used for several hours or more4 7b7 ,why should particular care be taken to see that acetylene cylinders are tightly closed when empty8 7c7 ,what action does oxygen have on oils and greases8 ,,lecture ,,number ,,three ,subject--,,welding ,,of ,,cast ,,iron 7,part ,one7 #a4 7a7 ,how is it possible to distinguish cast iron from such metals as malleable iron8 7b7 ,from semi-cast iron8 7c7 ,from cast steel8 #b4 7a7 ,what kind metal is used in making 8filler-rod0 used in the welding of cast iron8 7b7 ,what general rule can be laid down as to the relation of the metal in the 8filler-rod0 to the metal to be welded8 #c4 7a7 ,what are the characteristics of good cast iron 8filler-rods08 7b7 ,can piston rings and other small scraps of cast iron be used successfully as 8filler-rods08 ,explain why4 #d4 7a7 ,what is the purpose of a flux8 7b7 ,is a flux used in the welding of cast iron8 #e4 7a7 ,name one formula for making a cast-iron flux8 7b7 ,how often is the flux applied1 and by what means8 7c7 ,in what condition are fluxes kept when not in use8 #f4 7a7 ,how should the flame be held in the welding of all cast iron8 7b7 ,when and how is the 8filler-rod0 added to the weld8 #g4 7a7 ,name the one principal cause of blow-holes and hard spots in the weld4 7b7 ,mention some of the others4 #h4 7a7 ,when is it advisable to grind1 or 8,v0 out1 the ends of the pieces to be welded8 7b7 ,when is it not advisable8 #i4 7a7 ,does the application of heat cause contraction or expansion in metals8 7b7 ,are there any excepts to this rule8 ,name one4 #aj4 7a7 ,were two cast-iron bars measuring #b #ab inches and -inch thick1 to be welded1 end to end1 what precaution should be observed in laying out1 if the finished job is to measure just #bd inches long8 7b7 ,in what respect would this problem differ were the bars only #f inches originally and the finished job to measure #ab inches overall8 7c7 ,is the action of the metal in the weld a constant1 or a variable quantity depending upon the length of the bar in this problem8 ,,lecture ,,number ,,four ,subject--,,welding ,,of ,,cast ,,iron 7,part ,two7 #aa4 7a7 ,how could a spoke1 broken midway between the hub and rim1 of a #bd-;inch1 #d-spoke wheel 7otherwise intact7 be welded without preheating8 7,use a sketch if necessary to make method clear47 7b7 ,if a wheel of like size were broken only in the rim1 midway between spokes1 explain procedure in welding without preheating4 7c7 ,same sized wheel1 broken only in hub2--can weld be made without preheating8 ,give reasons for so thinking4 7d7 ,were breaks 7a71 7b7 and 7c7 all present in same wheel1 with rim fracture on opposite side of adjoining spoke from break in hub1 should welding be started at rim or hub8 ,why8 #ab4 7a7 ,in the building up of broken or missing teeth in cast-iron gears1 what procedure is necessary when no carbon blocks are available for forms8 7b7 ,if certain carbon centers from dry cell batteries are obtainable how should they be treated before allowing molten metal to come in direct contact with them8 7c7 ,what very important point must be uppermost in mind when dental work on gears is being done8 7d7 ,explain precautions taken in allowing work of this nature to cool4 #ac4 7a7 ,realizing that hard spots occur in most welds executed by the new welder and having learned the cause of their presence and how to overcome them1 would it not be possible to utilize this process for hardening parts which were subject to much wear and little strain8 ,explain procedure4 7b7 ,why is it necessary to preheat such pieces as the following before the weld is attempted2 broken water-jackets on gas-engine cylinders1 usually brought about by freezing1 and holes or cracks in crank cases1 caused by the loosening of a connection rod2 when lugs on the same cylinder1 the arms on the same crank case can be welded without preheating1 and ofttimes without even dismantling the motor8 ,,lecture ,,number ,,five ,subject--,,welding ,,of ,,cast ,,iron 7,part ,three7 #ad4 ,describe fully the manner in which two cast-iron bars measuring #a #f inches and #bd inches long1 are welded end to end1 citing preparations1 precautions1 and the procedure and materials necessary to execute and carry the weld through to a cool state4 ,,note4--,both gases are in the line hoses as far as the welding torch4 ,,lecture ,,number ,,six ,subject--,,welding ,,of ,,cast ,,iron 7,part ,four7 #ae4 7a7 ,are water jackets on cast-iron cylinder blocks welded in a cold1 or a preheated condition8 7b7 ,is this true under all conditions8 7c7 ,if a crack were found in the combustion head of a cylinder block and the entire water jacket and cylinder were cast in one1 how should this job be prepared in order to make a successful weld8 7d7 ,in welding a broken lug on the base of a cylinder block how should lug appear after weld is cold8 ,,lecture ,,number ,,seven ,subject--,,equipment #a4 ,describe the operation1 step by step1 taken to set up an oxy-acetylene welding plant1 from the assembling of the parts1 right through1 until a neutral welding flame is obtained4 7,if a sketch1 with the gas cylinders and parts numbered #a1 #b1 #c1 etc41 will assist in making description clear1 it may be used47 #b4 7a7 ,is it desirable to have a planed metal1 or a brick-top table for welding purposes8 7b7 ,explain why4 #c4 ,outline and describe briefly1 a simple method of building a popular type of welding table4 #d4 7a7 ,what is the name and style of bricks used in the welding shop8 7b7 ,name at least three purposes for which these bricks are used4 #e4 7a7 ,why does an emery wheel play such an important part in the oxy-acetylene welding industry8 7b7 ,why is it desirable to have a flexible shaft attachment for the emery wheel1 if possible8 7c7 ,name some of the important things a flexible shaft attachment is used for in the preparation and finishing of welds4 #f4 7a7 ,in what kind of containers is retort cement purchased in the commercial world8 7b7 ,where is retort cement used in the welding shop8 7c7 ,how does it differ from the ordinary clay or putty8 #g4 7a7 ,why should a blacksmith forge be added to the welding shop equipment if one is obtainable8 7b7 ,what two important tasks is a forge used for in the welding shop8 #h4 7a7 ,it is essential that several pails of water be located throughout the shop2 why should this be necessary8 7b7 ,mention a few instances where water is required in the welding shop4 #i4 ,explain fully why great care should be exercised in ventilating a shop where commercial welding is being done4 #aj4 7a7 ,describe one simple method of constructing a flux box4 7b7 ,what advantages has this type of container8 ,,lecture ,,number ,,eight ,subject--,,repairs #a4 ,what is the best method of locating a leak in either the oxygen or acetylene lines8 #b4 ,if a leak were found in a ground seat1 how could it be stopped if the nut on the coupling had been screwed up as far as possible8 #c4 ,name one method of attaching connections to hoses so that they will not blow off or pull off when pressure is applied4 #d4 ,how could either an oxygen or acetylene hose that had been burned or otherwise injured1 be repaired to withstand the gas pressure8 #e4 ,how could regulator be operated if the cross-bar for applying pressure upon the diaphragm springs were lost8 #f4 7a7 ,what procedure would be necessary to make connection if cylinder were supplied with an adaptor which would not fit the regulator connection and it could not be coupled up directly8 7b7 ,realizing that all cylinder connections about a regulator are generally supplied with a -inch taper pipe thread1 why do all manufacturers solder them in8 #g4 ,explain why oxygen high-pressure gauges are constructed with a loose back and a solid front4 #h4 7a7 ,where is the first place to seek trouble in a gauge if it leaks8 7b7 ,can such leaks be repaired8 7c7 ,describe method4 #i4 ,if either a high-or low-pressure gauge were injured beyond the repair state how could welding plant be kept in operation without it8 #aj4 7a7 ,what would be the trouble1 in shutting off a welding plant1 if there were a reading on the high-pressure gauge and none on the low-pressure gauge1 after permitting gas to escape from the hose8 7b7 ,how could the reading on this gauge be brought back to zero8 ,,lecture ,,number ,,nine ,subject--,,steel ,,welding 7,part ,one7 #a4 7a7 ,is the welding of steel more or less difficult than cast iron8 7b7 ,explain why4 #b4 7a7 ,why is the choice of the welding tip so important when working on steel8 7b7 ,what will result if the tip is too large8 7c7 ,if too small8 #c4 7a7 ,why is the choice of a 8filler-rod0 of a correct size so important for steel welding8 7b7 ,what will happen if the 8filler-rod0 is too large8 7c7 ,if too small8 #d4 7a7 ,what kind of a 8filler-rod0 is used in welding steel8 7b7 ,give a general rule covering relation of 8filler-rod0 to the metal being welded in all cases1 but one or two4 7c7 ,name one exception4 #e4 7a7 ,is a flux 7or scaling powder7 necessary in welding steel8 7b7 ,explain why4 #f4 7a7 ,how is the flame adjusted for steel welding8 7b7 ,what kind of a flame is generally used in finishing steel work8 7c7 ,why is this done8 #g4 7a7 ,how is the flame held when executing a steel weld8 7b7 ,how is the 8filler-rod0 held when making a steel weld8 #h4 7a7 ,is it necessary to 8,v0 out on steel the same as on cast iron8 7b7 ,explain why4 #i4 7a7 ,is a steel weld as strong as the original metal if not built up8 7b7 ,explain why4 #aj4 7a7 ,is the same provision made for expansion and contraction on steel as on cast iron8 7b7 ,give reasons for so thinking4 ,,lecture ,,number ,,ten ,subject--,,steel ,,welding 7,part ,two7 #aa4 7a7 ,what is meant by a 8crater0 in steel welding8 7b7 ,how are they removed from the weld8 #ab4 7a7 ,what are some methods and marks of distinguishing steel from other metals8 7b7 ,how is cast steel distinguished from cast iron8 #ac4 7a7 ,name some of the qualifications of a good 8filler-rod0 for mild steel welding4 7b7 ,in what manner does the 8filler-rod0 differ for the alloyed and high-carbon steels8 #ad4 7a7 ,in bringing the neutral flame in contact with the metal on a steel weld1 should the cone bend and spread on the surface1 or just lick it8 7b7 ,explain why4 #ae4 7a7 ,what is the principal cause for hard spots in steel welds8 7b7 ,what causes some of the others8 #af4 7a7 ,is it rolled steel or cast steel that does not expand when heated8 7b7 ,name one other metal that does not expand when heated4 #ag4 7a7 ,why are welds more difficult on sheet iron and steel than on some of the heavier pieces8 7b7 ,what can be used as a 8filler-rod0 on sheet metal work8 #ah4 7a7 ,what difficulty is generally encountered1 when making a long weld like on a steel tank8 7b7 ,how can this be overcome8 7c7 ,why do the open ends on sheet steel welds overlap in welding when same class of work on cast iron separates8 #ai4 7a7 ,what causes steel welds to carbonize8 7b7 ,what usually causes a burnt steel weld8 #bj4 ,describe fully how a broken automobile frame can be welded and re-enforced to make it stronger than originally4 ,,lecture ,,number ,,eleven ,subject--,,steel ,,welding 7,part ,three7 #ba4 7a7 ,what kind of a 8filler-rod0 is used in welding cast steel8 7b7 ,is a flux used8 #bb4 7a7 ,what kind of a 8filler-rod0 is employed when welding cast iron to steel8 7b7 ,what kind of a flux is used8 #bc4 7a7 ,can springs be successfully welded8 7b7 ,state reasons4 #bd4 7a7 ,why are crank-shaft welds so hard to execute successfully8 7b7 ,what kind of a 8filler-rod0 is used for best results on most crank-shafts8 7c7 ,what points does the welder consider when deciding whether a weld of this nature is advisable8 #be4 7a7 ,briefly describe the method of building up crank-shaft bearings that have been worn down4 7b7 ,what are some of the precautions taken in work of this kind8 #bf4 7a7 ,when automobile propeller shafts and rear axles break1 it is generally adjoining the square end4 ,is it advisable to weld this short piece on8 7b7 ,what is the correct procedure in a case of this kind8 #bg4 7a7 ,if a case-hardened ring-gear is to have its teeth built up or new ones added1 how is it handled after welding8 7b7 ,should all case-hardened work be so treated after welding8 #bh4 7a7 ,in welding two pieces of metal1 one of which is considerably lighter than the other1 how is the flame held in order to bring both pieces to a fusion at the same time8 #bi4 7a7 ,if a steel weld were to break in the line of weld1 how should it be prepared if it is to be rewelded8 7b7 ,does this procedure apply only to steel8 #cj4 ,were a hole #f inches square in a sheet of steel to be welded up without preheating1 what would be the approximate size of the patch necessary and how would it be prepared1 in order to take care of the expansion and contraction strains8 ,,lecture ,,number ,,twelve ,subject--,,steel ,,welding 7,part ,four7 #ca4 7a7 ,why should a steel weld of any kind be executed as rapidly as possible8 7b7 ,what will happen if steel is kept in a heated condition too long8 7c7 ,why should a change be in evidence under these conditions8 #cb4 7a7 ,explain what is meant by a 8dished0 patch1 for boiler or thin armor plate8 7b7 ,draw such a patch4 7c7 ,how is a patch of this nature prepared8 #cc4 7a7 ,what is meant by a 8corrugated0 patch for boiler or thin armor plate8 7b7 ,sketch such a patch4 7c7 ,how is this kind of a patch prepared8 #cd4 7a7 ,what advantages has a 8corrugated0 patch over one that is 8dished08 7b7 ,where are 8corrugated0 patches used extensively8 #ce4 7a7 ,how are boiler flues prepared for re-tipping8 7b7 ,sketch a simple jig for holding such pieces in place for welding4 #cf4 7a7 ,describe how lengths of various sized pipe can be welded together end to end4 7b7 ,what precautions are necessary when executing such welds8 #cg4 7a7 ,when welding large steel castings why is it almost always advisable to preheat the work8 7b7 ,why is preheating so necessary on vanadium and other alloyed steels8 #ch4 ,why is it desirable to chip out the sand and thin scale formations1 in and around blow-holes in steel castings before filling in8 #ci4 7a7 ,why do the majority of good welders bend their steel 8filler-rods0 at right angles about #f inches from the end8 7b7 ,why isn't this being done on cast iron8 #dj4 7a7 ,what advantage is there in making a vertical weld from the top down1 rather than starting from the bottom and working up8 7b7 ,in welding overhead why is it so important that the work be in a molten state before adding the 8filler-rod08 7c7 ,in overhead welding1 why doesn't the metal drop when in a molten state8 ,,lecture ,,number ,,thirteen ,subject--,,oxy-,,acetylene ,,cutting #a4 ,explain fully which parts of an oxy-acetylene cutting plant are different from a welding unit4 #b4 7a7 ,if there is a difference in either of the regulators1 mention which one it is4 7b7 ,what is the difference8 7c7 ,why is it necessary8 #c4 7a7 ,is it possible to weld with a cutting torch8 7b7 ,what precaution is necessary if this is done8 7c7 ,why isn't this process used8 #d4 ,explain how cutting can be done with the welding torch if necessary4 #e4 7a7 ,in cutting by the oxy-acetylene process1 which does the cutting1 the oxygen jet or the neutral flame8 7b7 ,what action has the oxygen jet on the metal8 7c7 ,what part does the neutral flame play in cutting8 #f4 ,can oxygen or acetylene under sufficient pressure be made to cut individually8 ,explain fully4 #g4 ,why is it specially important that armored hose be used on the oxygen line when making heavy cuts8 7,give at least two reasons47 #h4 7a7 ,how is a cutting torch lighted8 ,describe in detail4 7b7 ,how is cut started on metal8 7c7 ,how is torch held in regard to metal being cut8 #i4 7a7 ,is it possible to successfully cut cast iron8 7b7 ,wrought iron8 7c7 ,cast steel8 7d7 ,rolled steel8 #aj4 7a7 ,cutting can be done under water with ordinary cutting apparatus2 why doesn't the flame go out when submerged8 7b7 ,what additional equipment is generally used in underwater cutting8 ,,lecture ,,number ,,fourteen ,subject--,,brass ,,welding #a4 ,explain as fully as possible the chief characteristics of a good 8filler-rod0 for brass welding4 #b4 7a7 ,is a flux used in welding brass8 7b7 ,what is one way of making a good flux for brass8 #c4 7a7 ,what kind of a flame is used in brass welding8 7b7 ,why8 #d4 7a7 ,in what position is the flame held in welding brass8 7b7 ,how should the 8filler-rod0 be held8 #e4 7a7 ,is it advisable to 8,v0 out or burn off the ends of brass work to be welded8 7b7 ,explain why4 #f4 7a7 ,what causes the dense white fumes to appear when fusing brass8 7b7 ,what is cause of brass welds being porous8 #g4 ,why should brass work not be disturbed when red hot8 #h4 ,what is the most difficult part of brass welding as a whole8 #i4 ,why are brass welds generally cooled in water as soon as fusion is completed8 #aj4 ,why is it difficult for the beginner to weld heavy pieces of brass8 ,,lecture ,,number ,,fifteen ,subject--,,welding ,,of ,,malleable ,,iron #a4 7a7 ,can malleable iron be successfully welded8 7b7 ,what is the most successful method of joining two pieces of malleable iron8 #b4 ,what are three methods of detecting malleable iron8 #c4 7a7 ,what kind of 8filler-rod0 is used on malleable iron8 7b7 ,are 8filler-rods0 of malleable iron satisfactory8 7c7 ,what kind of flux is used on malleable iron work8 #d4 7a7 ,how is a malleable iron casting prepared for welding8 7b7 ,how hot should work be1 previous to adding 8filler-rod08 7c7 ,what will occur if too much heat is applied8 #e4 7a7 ,in what respect does the adjustment of the flame differ on malleable iron from that of cast iron and steel8 7b7 ,how is the flame held in relation to the work8 7c7 ,does the flame come in direct contact with the 8filler-rod08 #f4 7a7 ,is more1 or less1 surface covered by the 8filler-rod0 on malleable iron than on cast iron8 7b7 ,why8 #g4 7a7 ,how should malleable iron be cooled8 7b7 ,is this the same as in welding brass8 #h4 ,on what part of machinery does a welder generally expect to find malleable iron castings8 #i4 ,explain carefully how a malleable iron automobile1 axle or transmission1 housing that has been cracked or broken1 can be re-enforced so that it will be stronger than ever4 #aj4 ,describe very briefly how malleable iron is made and in what respect it differs from cast iron when cold1 and also when under the influence of the oxy-acetylene flame4 ,,lecture ,,number ,,sixteen ,subject--,,carbon ,,burning #a4 7a7 ,explain what is meant by carbon burning4 7b7 ,in what respect is it used extensively8 #b4 7a7 ,will oxygen gas burn alone or does it merely aid combustion8 7b7 ,will carbon in a free state burn8 #c4 7a7 ,why is it advisable to remove only the spark plugs and not the entire valve cap or 8bonnet0 when burning carbon in a gas engine8 7b7 ,can it be done either way8 #d4 7a7 ,does it make a difference if the carbon is hard and dry in the cylinder8 7b7 ,what will help in such cases8 #e4 7a7 ,if the cylinder is rather oily does this make a difference8 7b7 ,does the presence of oil aid or retard combustion8 #f4 7a7 ,what precautions are necessary before carbon burning is attempted8 7b7 ,how is asbestos paper used in carbon burning8 7c7 ,name a good substitute for asbestos paper when carbon burning4 #g4 7a7 ,is there any danger of warping the valves and overheating the cylinder and piston when burning carbon8 7b7 ,what is the effect of carbon burning on aluminum pistons8 #h4 7a7 ,what pressure is used on the oxygen line for carbon burning8 7b7 ,will carbon burning re-grind valves8 #i4 7a7 ,how long should the burning be done8 7b7 ,how often is carbon burning recommended for a gas engine8 7c7 ,if there are any carbon particles or sand left in the cylinder after burning is done how are they removed8 #aj4 ,describe how the carbon is removed from a four-cylinder engine1 paying particular attention to details such as lighting1 which part of the head the torch is played on first1 what does the burning and where the carbon goes4 ,,lecture ,,number ,,seventeen ,subject--,,preheating ,,agencies #a4 7a7 ,what is meant by preheating as applied to the oxy-acetylene welding industry8 7b7 ,what are several fuels which can be used very successfully for preheating8 #b4 ,name the three principal reasons why parts to be welded are generally preheated4 #c4 7a7 ,why is charcoal considered the best preheating agent for general welding8 7b7 ,why should it not be used to any great extent in closed rooms during the winter months8 7c7 ,if used during the winter what precautions are observed8 #d4 7a7 ,mention two materials which are used extensively for building up ovens and doing the preheating4 7b7 ,what kind of brick is used8 #e4 7a7 ,how much should cast iron be preheated8 7b7 ,brass or bronze8 7c7 ,aluminum8 #f4 ,sketch and describe how a temporary brick preheating oven should be built1 giving all dimensions1 such as3 length1 width and height and reasons for them4 #g4 ,explain how a cylinder block with a broken water jacket is set up for preheating2 how oven is built for charcoal fire2 how fire is started2 how block is protected while welding and how it is returned to a cold state4 #h4 7a7 ,what precautions are necessary in setting up and preheating aluminum8 7b7 ,if piece is to be turned while in the fire1 what provision is made in building up oven8 #i4 ,in which cases is preheating absolutely necessary in order to make a satisfactory weld8 #aj4 7a7 ,give a sketch showing a preheating torch for use on illuminating gas and compressed air1 which can be constructed very easily4 7b7 ,why are preheating torches not popular for general welding8 7c7 ,where are they used in numbers8 ,,lecture ,,number ,,eighteen ,subject--,,aluminum ,,welding 7,part ,one7 #a4 7a7 ,is the welding of aluminum1 more or less difficult than such metals as cast iron and steel8 7b7 ,explain why4 #b4 7a7 ,name the two methods of making aluminum welds4 7b7 ,can they be combined8 7c7 ,why8 #c4 7a7 ,what kind of a 8filler-rod0 is used in welding aluminum8 7b7 ,is a flux used8 ,why8 #d4 7a7 ,is a cast or drawn 8filler-rod0 preferred8 7b7 ,name the two important metals which should be present and the percentage of each in the 8filler-rod40 #e4 7a7 ,how should the flame be adjusted for aluminum welding8 7b7 ,how is the flame held in relation to the work8 #f4 7a7 ,how is the 8filler-rod0 added8 7b7 ,in what respect does this differ from all other metals8 7c7 ,why can this be done8 #g4 7a7 ,name the principal characteristics of aluminum with regard to heat4 7b7 ,what other metal acts in a similar manner8 #h4 7a7 ,is it necessary to 8,v0 out aluminum for the same reasons as other metals8 7b7 ,explain why4 #i4 7a7 ,will an aluminum welding be as strong as the original8 7b7 ,give reasons4 #aj4 7a7 ,what kind of a tool is used to aid in making an aluminum weld by most welders8 7b7 ,how is such a tool made8 ,,lecture ,,number ,,nineteen ,subject--,,aluminum ,,welding 7,part ,two7 #aa4 7a7 ,what kind of files are used to finish aluminum welds8 7b7 ,in what respect do they differ from the ordinary kind8 #ab4 7a7 ,in which hand is the welding torch held in aluminum work8 7b7 ,in which1 the 8filler-rod08 7c7 ,the puddle stick8 #ac4 7a7 ,what materials are used to 8back-up0 aluminum work for preheating8 7b7 ,describe fully how aluminum is 8backed-up0 previous to preheating1 in order to prevent the collapse of metal while welding4 #ad4 7a7 ,how quick does the heavy coating or aluminum oxide form on a clean hot piece of aluminum8 7b7 ,will the metal flow together when this oxide is present8 7c7 ,how is it overcome8 #ae4 7a7 ,is it advisable to weld aluminum from one side only or from both sides8 7b7 ,why8 #af4 ,in preheating aluminum with charcoal1 what precautions are taken in setting up2 in starting the fire2 during the welding operation1 and in cooling the piece8 #ag4 7a7 ,are preheating torches played directly on aluminum work8 7b7 ,what kind of an oven is used8 #ah4 7a7 ,is it necessary to heat the whole of an aluminum crank-case if one part has to be preheated8 7b7 ,give reasons4 #ai4 7a7 ,are clamps used to hold parts in place on preheated aluminum8 7b7 ,explain why4 #bj4 ,when starting to weld a cold piece of aluminum1 the flame is brought in contact with the work and held there much longer than on a similar size piece of steel before any apparent change occurs4 ,how is this accounted for1 knowing that aluminum has a much lower melting point that steel8 ,,lecture ,,number ,,twenty ,subject--,,aluminum ,,welding 7,part ,three7 #ba4 ,explain fully why it is necessary to employ greater speed in the welding of aluminum than on any other metal8 #bb4 7a7 ,what is retort cement8 7b7 ,how does it differ from ordinary clay8 7c7 ,for what purpose is it used in aluminum welding8 #bc4 7a7 ,when performing an aluminum weld by the puddle system1 is the welder dependent upon the flame1 the 8filler-rod0 or the puddle stick1 for the fusion of the metal8 7b7 ,give explanations4 #bd4 7a7 ,what method of welding is used when executing a vertical weld on aluminum8 7b7 ,why isn't the other method used8 7c7 ,is the vertical welding of aluminum to be avoided8 #be4 7a7 ,can aluminum welds be made overhead8 7b7 ,explain why4 #bf4 7a7 ,is the same method used on aluminum as in cast iron in welding from the closed end1 toward the open8 7b7 ,is this procedure necessary on preheated work8 #bg4 7a7 ,if a suspension arm1 of a 8,u0 type1 on an aluminum crank case were to break about #c or #d inches from the body of the case1 could it be welded in place without dismantling the motor8 7b7 ,explain in detail how such an arm should be welded4 #bh4 ,due to the contraction and expansion1 it is very difficult to have the bolt hole1 in the end of an aluminum suspension arm that has been welded1 return exactly to its former position4 ,how is this difficulty provided for8 #bi4 7a7 ,should a section of an aluminum crank case be missing1 would it be advisable to build up a new part with the 8filler-rod0 or to cast a new part in a mold and then weld it in8 7b7 ,under what conditions should the above be done8 #cj4 7a7 ,if it were found that an aluminum crank case after being welded1 had one corner about -inch lower than the rest of the case and it had not affected any of the bearings1 could it still be reclaimed8 7b7 ,give procedure4 ,,index ,a ,absorbent1 acetone as an1 #bf1 #ca -- asbestos as an1 #ca -- charcoal as an1 #ca -- mineral wool as1 #ha ,acetone as an absorbent1 #bf1 #ca ,acetylene cylinders1 construction of1 #ca ,acetylene gas1 temperature of flame of1 #a ,adapter1 types of1 #df ,aluminum1 backing up in welding1 #aad -- charcoal in welding1 #aaf -- contraction and expansion in welding1 #aaf -- clamps1 use of in welding1 #aae -- crank cases1 welding1 #aah -- filler-rods in welding1 #aab1 #aae -- flux method of welding1 #aji1 #aaa -- oxidation of bright surfaces in welding1 #aac -- preheating in welding1 #aaf1 #aag -- preheating1 method of1 #eb -- puddle and flux systems of welding compared1 #aaa -- puddle method of welding1 #aji1 #aaa -- strains1 avoiding internal1 #aah -- suspension arm of crank case1 repairing1 #aah -- tip used in welding1 #aji -- welding1 #aji-aag -- welding from one side1 #aad ,apparatus1 classes of welding1 #ai -- desirability of securing the best1 #add -- emery wheel1 need of1 #da -- high-pressure welding1 #bj -- low-pressure welding1 #ai -- medium-pressure welding1 #ai -- metal top table1 disadvantages of1 #ci -- mixing chambers1 #ba -- oils and grease to be avoided1 #cg -- oxy-acetylene1 for cutting1 #abe -- regulator1 #bb -- -- types of1 #bd -- required in welding1 #ai-bf -- -- replacing lost cross-bar1 #df -- setting up1 manner of1 #ca1 #cb -- shop equipment1 #ci1 #dc -- shutting off1 procedure in1 #ce ,apparatus repairs1 #dd-ej -- -- adapters1 types of1 #df -- -- gauges1 operation of1 #di -- -- gauges1 safety1 #dg1 #dh -- -- hose clamps1 #de -- -- hose1 repairing leaky1 #de -- -- leaks1 method of locating1 #dd -- -- leaky threads1 repairing1 #dd ,asbestos as an absorbent1 #ca -- in aluminum welding1 #aaf -- paper cover protection1 #ee ,automobile frame1 welding1 #ia ,automobile1 propeller shafts1 welding1 #ie ,axles1 automobile1 welding1 #ie ,b ,blow holes1 causes of1 #fe ,boiler flues retipping1 #ih1 #ii ,boiler1 8corrugated0 patches1 #ajb1 #ajc -- 8dished0 patches in repairs to1 #aja -- 8,l0 patches in repairing1 #ajc -- repairing1 #ii-aja ,borax as a brass flux1 #ajg ,brass1 alloy of1 #ajf -- filler-rod in welding1 #ajf -- flux in welding1 #ajg -- fumes in welding1 #ajh -- melting-point1 #ajf ,brass welding1 #ajf-ajh ,bronze for welding purposes1 #abc -- welding malleable iron with1 #aba ,c ,carbon burning1 #ace-add -- -- in gasoline engine1 #acf-aci -- -- theory of1 #aci ,carbonizing flame1 #cd ,cast iron1 welding of1 #eh-hj -- -- -- -- blow holes1 causes of1 #fe -- -- -- -- charcoal as preheating agent1 #gf -- -- -- -- combustion head of cylinder1 repairing1 #gh1 #gi -- -- -- -- contraction of metals in1 prevention of1 #ga -- -- -- -- expansion and contraction of metals1 #fe-fg -- -- -- -- filler rod1 #fa -- -- -- -- flux a cleansing agent1 #fa -- -- -- -- flux1 manner of application of1 #fb -- -- -- -- flux1 simple substitute for1 #fa -- -- -- -- gasoline engine cylinder block1 repairing1 #ge1 #gf -- -- -- -- gear wheel teeth1 three ways of restoring1 broken1 #ga-gd -- -- -- -- hardening parts by use of carbonizing flame1 #gd -- -- -- -- lugs1 welding on cylinder block1 #hj -- -- -- -- methods of distinguishing metals1 #fj -- -- -- -- preparations for1 #fg -- -- -- -- procedure in1 #fc1 #fd1 #fg-gj -- -- -- -- successful weld1 criterion of1 #ge -- -- -- -- tip1 size of1 #fc ,cast steel1 procedure in welding of1 #hh ,charcoal as an absorbent1 #ca -- as preheating agent1 #gf -- in aluminum welding1 #aaf ,clamps1 inadvisable in welding aluminum1 #aae ,contraction and expansion in aluminum welding1 #aaf -- -- -- in preheating1 #ec -- -- -- in welding steel1 #hg ,contraction of metal in welding1 prevention of1 #ga 8,corrugated0 patch1 method of making1 #ajb1 #ajc ,crank cases1 aluminum1 repairing1 #aah ,crank shafts1 welding methods1 #ic1 #id ,crater1 development and removal of1 #hh ,cross-bar1 replacing lost1 #df ,cutting by oxy-acetylene process1 #f ,cutting with oxy-acetylene1 #abe-acd ,cutting torch1 welding torch and1 compared1 #abg ,cylinder block1 repairing cast-iron gasoline engine1 #ge1 #gf ,cylinder bore1 device for polishing1 #gi1 #hj ,cylinders1 acetone as absorbent in1 #bf ,d ,decarbonization of automobile engines1 #acf1 #aci ,demand for oxy-acetylene operators1 #ag 8,dished0 patch in boiler repairs1 #aja ,e ,emery wheel1 value of in welding shop1 #da ,expansion and contraction of metals1 #fe-fg -- -- -- in welding1 #hg ,explosions1 precautions against1 #cg ,f ,feather flame1 #cc1 #ce ,filler rod1 #hi -- -- in brass welding1 #ajf -- -- in welding malleable iron1 #abb -- -- metal in1 #fa -- -- used in aluminum welding1 #aab -- -- used in welding steel1 #hb1 #ia ,fire brick1 in aluminum welding1 #aaf -- -- preheating oven of1 #ed -- -- table1 #ci ,flame1 carbonizing1 #cd -- feather1 #cc1 #ce -- neutral #cc1 #ce -- oxidizing1 #cd -- torch1 cutting under water with1 #acc -- varieties of1 adjustment of1 #cb1cc ,flashbacks1 causes of1 #ba1 #bb -- prevention of1 #bb ,flux1 application1 manner of1 #fb -- container1 #db -- in brass welding1 #ajg -- office of1 #fa -- substitute1 a simple and effective1 #fa ,g ,gasoline engine1 carbon1 how to remove from1 #acf-aci ,gasoline tanks1 necessity for caution in repairing1 #ajc ,gauges1 operation of1 #di -- safety1 #dg1 #dh ,gear wheel teeth1 three ways of restoring broken1 #ga-gd ,glossary1 #ade-adh ,goggles1 eye1 #ce ,h ,hardening parts through use of carbonizing flames1 #gd ,heat in welding malleable iron1 #abc ,high-pressure regulated1 #bd ,hose1 armored1 used on oxygen line1 #acc -- clamps in repairing1 #de -- leaky1 #de ,l 8,l0 patches1 #ajc ,leaks1 method of discovering1 #dd -- repairing threads1 #dd ,lectures1 #adi-aff ,low-pressure regulator1 #bd ,lugs1 welding on cylinder block1 #hj ,m 8,maine10 battleship1 wreck cut up with oxy-acetylene gas1 #f ,malleable iron1 bronze1 welding with1 #aba1 #abc -- -- clean surface1 necessity of in welding1 #abb -- -- heat in welding1 #abc -- -- melting to be avoided1 #aba -- -- preheating unusual1 #abc -- -- steel strips in welding1 #abc -- -- welding1 #abj-abd ,metals1 methods of distinguishing1 #fj1 #hg ,mineral wool as an absorbent1 #ca ,mixing chamber1 #ba ,n ,needle valve1 regrinding leaky1 #bf ,neutral flame1 #cc1 #ce ,o ,oils and grease1 importance of avoiding use of1 #cg ,operation in oxy-acetylene welding1 #bg-ch ,operator1 standing position of1 relative to work1 #cb ,overhead welding1 #aje ,oxidation of bright surfaces in aluminum1 #aac ,oxidizing flame1 #cd ,oxy-acetylene1 cutting metals with1 #f -- flame1 varieties of adjustment of1 #cb1 #cc -- in airplane construction1 #i -- in automobile manufacture1 #aj -- in boiler shops1 #aj -- in brass and copper work1 #aj -- in commercial welding1 #aa -- in electric railways1 #aa -- in foundries1 #aa -- in lead burning1 #ab -- in lumber mills1 #ab -- in machine shops1 #ab -- in manufacturing1 #ab -- in mines1 #ac -- in pipe work1 #ac -- in plate welding1 #ac -- in power plants1 #ac -- in railroad work1 #ac -- in rolling mills1 #ad -- in sheet metal manufacture1 #ae -- in shipyards1 #ae -- in the forge shop1 #aa -- in tractor industry1 #af -- lake boats cut apart by1 #h -- operators1 demand for1 #ag -- scrap cut up by1 #f -- scrap yards1 #ae -- structural steel1 #ae -- torch as fire department tool1 #g -- torch can be used under water1 #h -- varied uses of1 #i ,oxy-acetylene cutting1 #abe-acd -- -- apparatus for1 #abe -- -- arrangement of oxygen line1 #abe -- -- cutting torch1 extemporizing a1 #acb -- -- flame1 cutting under water with1 #acc -- -- flickering of oxygen jet1 #abg -- -- high-pressure and low-pressure regulators compared1 #abg -- -- hose1 armored1 in1 #acc -- -- pressure of acetylene and oxygen1 #abi -- -- steel and cast-iron1 #aca -- -- torch in preparing steel1 #aca -- -- torch1 cutting and welding compared1 #abg -- -- torch1 using cutting1 for welding purposes1 #acc ,oxy-acetylene welding1 apparatus required in1 #ai-bf -- -- a fusing process1 #fb -- -- auto-frame repairs1 #d -- -- classes of apparatus1 #ai -- -- containers1 seamless1 made through use of1 #c -- -- definition of1 #a -- -- fire-brick table1 #ci -- -- future of1 #ag -- -- growth of process1 #h -- -- locomotive frames1 #d -- -- metal-top table1 disadvantages of1 #ci -- -- mixing chambers1 #ba -- -- operation in1 #bg-ch -- -- principle of1 #abe -- -- repairs through1 #c1 #e -- -- shop equipment1 #ci-dc -- -- variety of applications of1 #c ,oxygen1 cylinders1 #bg -- gas1 result of too much1 #ce -- office of in combustion1 #bg -- table of different pressures of1 at various temperatures1 #bi ,p ,preheating1 aluminum1 #aag -- asbestos paper for oven1 #ee -- charcoal in1 #ec -- extraction and expansion in1 #ec -- drafts1 protecting work from1 in1 #ed -- fuels used in1 #ec -- in aluminum work1 #aaf -- ovens1 #ef -- reasons for1 #ea -- setting up work1 #ef -- torch for1 burning city gas1 #ed -- varied heats for different metals1 #eb ,preheating agencies1 #ea-eg -- -- fire-brick oven1 #ed -- -- ovens1 #ee1 #ef -- -- torch1 burning city gas1 #ed ,propeller shafts1 welding automobile1 #ie ,puddle method of welding aluminum1 #aji1 #aaa ,r ,regulator1 care of1 #be -- construction and action of1 #bb1 #bc -- types of1 #bd ,ring gears1 building teeth on case-hardened1 #if ,retort cement1 #db ,s ,sheet steel and iron1 welding1 #hi ,ships1 repairs to seized ,german by acetylene process1 #e ,shop equipment1 #ci-dc -- -- blacksmith forge1 #db -- -- carbon rods and blocks1 #dc -- -- emery wheel1 #da -- -- fire-brick table1 #ci -- -- flux container1 #db -- -- retort cement1 #db -- -- ventilation1 #dc ,sparks1 characteristic thrown off by emery wheel1 #ei ,spring's1 welding1 futility of1 #ib1 #ic ,steel1 automobile frame1 welding1 #ia -- automobile axles1 welding of1 #ie -- automobile propeller shafts1 welding1 #ie -- boiler flues1 retipping1 #ih1 #ii -- boiler repairs1 #ii-aja -- cast1 procedure in welding1 #hh -- construction and expansion in welding1 #hg -- 8corrugated0 patch1 #ajb1 #ajc -- crank-shafts1 welding of1 #ic1 #id -- craters1 formation of1 in welding1 #hh -- definition1 #ha -- 8dished0 patch in boiler repairs1 #aja -- filler-rod used in welding1 #hb -- filler-rod to be used in welding1 #ig -- flame control in welding1 #ha1 #hb -- hard spots1 formation of in welding1 #hi -- heat treatment in welding unequal sized pieces1 #ig -- internal strains in welding1 #ajj -- 8,l0 patches1 #ajc -- metals1 methods of distinguishing in welding1 #hg -- methods of welding1 #hb-hf -- outside appearances in welding1 #hg -- overhead welding1 #aje -- sheet1 welding1 #hi -- speed required in welding1 #ig -- springs1 inadvisability of welding1 #ib1 #ic -- susceptibility of when molten1 #ig -- teeth1 building up of1 #if -- vertical welding of1 #ajd -- weld1 broken1 method of repairing1 #if -- welding1 difficulties of1 #ha1 #ib ,steel welding1 #ha-aje ,t ,table of different pressures of oxygen at various temperatures1 #bi ,tanks inflammable gases1 caution to be used in welding1 #ajc ,teeth1 building up of1 #if ,temperature of acetylene gas flame1 #a ,tip1 size of in welding1 #fc ,v ,ventilation1 #ef1 #ajh -- importance of in welding shop1 #dc ,vertical welding1 #ajd 8,v-ing0 metal in welding1 #fc ,w ,welding1 aluminum1 #aji-aag -- brass1 #ajf-ajh -- cast iron1 procedure1 #fg-gj -- malleable iron1 #abj-abd -- methods of distinguishing between metals1 #eh -- sparks in determining kind of metals in1 #eh ,welding of steel1 #ha-aje -- -- -- broken weld1 manner of repairing1 #if -- -- -- cast1 procedure in1 #hh -- -- -- contraction and expansion in1 #hg -- -- -- crank shafts1 #ic1 #id -- -- -- craters1 formation of in1 #hh -- -- -- filler-rod in1 #ia -- -- -- hard spots1 formation of in1 #hi -- -- -- heat treatment in unequal sized pieces1 #ig -- -- -- methods of1 #hb-hf -- -- -- overhead welding1 #aje -- -- -- springs1 futility of welding1 #ic -- -- -- teeth1 building up of1 #if -- -- -- vertical welding1 #ajd ,illustration ,wiley ,special ,subject ,catalogues ,for convenience a list of the ,wiley ,special ,subject ,catalogues1 envelope size1 has been printed4 ,these are arranged in groups--each catalogue having a key symbol4 7,see special ,subject ,list ,below74 ,to obtain any of these catalogues1 send a postal using the key symbols of the ,catalogues desired4 #a--;,agriculture4 ,animal ,husbandry4 ,dairying4 ,industrial ,canning and ,preserving4 #b--;,architecture4 ,building4 ,masonry4 #c--;,business ,administration and ,management4 ,law4 ,industrial ,processes3 ,canning and ,preserving2 ,oil and ,gas ,production2 ,paint2 ,printing2 ,sugar ,manufacture2 ,textile4 ,,chemistry #d;a ,general2 ,analytical1 ,qualitative and ,quantitative2 ,inorganic2 ,organic4 #d;b ,electro- and ,physical2 ,food and ,water2 ,industrial2 ,medical and ,pharmaceutical2 ,sugar4 ,,civil ,,engineering #e;a ,unclassified and ,structural ,engineering4 #e;b ,materials and ,mechanics of ,construction1 including2 ,cement and ,concrete2 ,excavation and ,earthwork2 ,foundations2 ,masonry4 #e;c ,railroads2 ,surveying4 #e;d ,dams2 ,hydraulic ,engineering2 ,pumping and ,hydraulics2 ,irrigation ,engineering2 ,river and ,harbor ,engineering2 ,water ,supply4 #e;e ,highways2 ,municipal ,engineering2 ,sanitary ,engineering2 ,water ,supply4 ,forestry4 ,horticulture1 ,botany and ,landscape ,gardening4 #f--;,design4 ,decoration4 ,drawing3 ,general2 ,descriptive ,geometry2 ,kinematics2 ,mechanical4 ,,electrical ,,engineering--,,physics #g--;,general and ,unclassified2 ,batteries2 ,central ,station ,practice2 ,distribution and ,transmission2 ,dynamo-,electro ,machinery2 ,electro-,chemistry and ,metallurgy2 ,measuring ,instruments and ,miscellaneous ,apparatus4 #h--;,astronomy4 ,meteorology4 ,explosives4 ,marine and ,naval ,engineering4 ,military4 ,miscellaneous ,books4 ,,mathematics #i--;,general2 ,algebra2 ,analytic and ,plane ,geometry2 ,calculus2 ,trigonometry2 ,vector ,analysis4 ,,mechanical ,,engineering #aj;a ,general and ,unclassified2 ,foundry ,practice2 ,shop ,practice4 #aj;b ,gas ,power and ,internal ,combustion ,engines2 ,heating and ,ventilation2 ,refrigeration4 #aj;c ,machine ,design and ,mechanism2 ,power ,transmission2 ,steam ,power and ,power ,plants2 ,thermodynamics and ,heat ,power4 #aa--,mechanics4 #ab--,medicine4 ,pharmacy4 ,medical and ,pharmaceutical ,chemistry4 ,sanitary ,science and ,engineering4 ,bacteriology and ,biology4 ,,mining ,,engineering #ac--;,general2 ,assaying2 ,excavation1 ,earthwork1 ,tunneling1 ,etc42 ,explosives2 ,geology2 ,metallurgy2 ,mineralogy2 ,prospecting2 ,ventilation4 ,transcriber's ,notes ,inconsistencies have not been standardised1 except as mentioned below4 ,changes made3 ,illustrations have been moved out of text paragraphs4 ,some obviously missing punctuation has been inserted1 some unnecessarily repeated words and unnecessary punctuation have been deleted1 some obvious minor typographical errors have been corrected silently4 ,the paragraph numbers have been standardised to bold face numbers4 ,page #cg3 ,it is quite necessary that these torch valves closed 444 changed to ,it is quite necessary that these torch valves are closed 4444 ,page #dh3 444 remove the guage from the regulator 444 changed to 444 remove the gauge from the regulator 4444 ,page #afi3 7,hose7 clamps in reparing 444 changed to 7,hose7 clamps in repairing 4444