,oxy-,acetyl5e ,weld+ & ,cutt+ ,electric1 ,=ge & ,!rmit ,weld+ ,toge!r ) ,relat$ ,me?ods & ,mat]ials ,us$ 9 ,metal ,work+ ,& ,! ,oxyg5 ,process = ,removal ( ,c>bon ,by ,,h>old ,p4 ,,manly ,,preface ,9 ! prep>ation ( ?is "w1 ! object has be5 to cov] n only ! sev]al processes ( weld+1 b also ^? o!r processes :i* are s closely alli$ 9 me?od & results z to make !m a "p ( ! :ole subject ( jo9+ metal to metal ) ! aid ( heat4 ,! workman :o wi%es to h&le 8 trade f />t to f9i% f9ds t x is necess>y to become famili> ) c]ta9 o!r op]ations :i* prec$e or foll[ ! actual jo9+ ( ! metal p>ts1 ! purpose ( ^! op]ations be+ to add or reta9 c]ta9 desirable qualities 9 ! mat]ials be+ h&l$4 ,= ?is reason ! foll[+ subjects h be5 includ$3 ,anneal+1 temp]+1 h>d5+1 heat treatm5t & ! re/oration ( /eel4 ,9 ord] t ! us] may und]/& ! und]ly+ pr9ciples & ! mat]ials employ$ 9 ?is "w1 mu* practical in=mation is giv5 on ! uses & *>act]i/ics ( ! v>i\s metals2 on ! production1 h&l+ & use ( ! gases & o!r mat]ials :i* are a "p ( ! equipm5t2 & on ! tools & accessories = ! production & h&l+ ( ^! mat]ials4 ,an exam9ation w %[ t ! greate/ usefulness ( ?is book lies 9 ! fact t all necess>y in=mation & data has be5 includ$ 9 "o volume1 mak+ x possible = ! workman to use "o s\rce = secur+ a k ( bo? pr9ciple & practice1 prep>ation & f9i%+ ( ! "w1 & bo? l>ge & small repair "w z well z manufactur+ me?ods us$ 9 metal work+4 ,an ef=t has be5 made to elim9ate all matt] :i* is n ( direct usefulness 9 practical "w1 :ile includ+ all t ^? engag$ 9 ?is trade f9d necess>y4 ,to ?is end1 ! descriptions h be5 limit$ to ^? me?ods & accessories :i* are f\nd 9 actual use today4 ,= ! same reason1 ! "w includes ! application ( ! rules laid d[n by ! insurance und]writ]s :i* gov]n ?is "w z well z in/ructions = ! prop] c>e & h&l+ ( ! g5]ators1 tor*es & mat]ials f\nd 9 ! %op4 ,special att5tion has be5 giv5 to def9ite directions = h&l+ ! diff]5t metals & alloys :i* mu/ be h&l$4 ,! in/ructions h be5 arrang$ to =m rules :i* are plac$ 9 ! ord] ( _! use dur+ ! "w describ$ & ! "w has be5 subdivid$ 9 su* a way t x w be f\nd possible to secure in=mation on any "o po9t desir$ )\t ! necessity ( sp5d+ "t 9 o!r fields4 ,! facts :i* ! exp]t weld] & metalwork] f9ds x mo/ necess>y to h readily available h be5 secur$1 & prep>$ especially = ?is "w1 & ^? ( mo/ g5]al use h be5 comb9$ ) ! *apt] on weld+ practice to :i* !y apply4 ,! size ( ?is volume has be5 kept z small z possible1 b an exam9ation ( ! alphabetical index w %[ t ! range ( subjects & details cov]$ is complete 9 all respects4 ,?is has be5 accompli%$ ?r\gh c>eful classification ( ! cont5ts & ! elim9ation ( all repetition & all !oretical1 hi/orical & simil> matt] t is n absolutely necess>y4 ,free use has be5 made ( ! in=mation giv5 by ^? manufactur]s :o are recogniz$ z ! lead]s 9 _! respective fields1 ?us insur+ t ! "w is ?or\ghly practical & t x repres5ts pres5t day me?ods & practice4 ,,! ,,au?or4 ,,cont5ts ,,*apt] ,i ,,metals ,,& ,,alloys--,,heat ,,treatm5t3--,! ,use & ,*>act]i/ics ( ! ,indu/rial ,alloys & ,metal ,elem5ts--,anneal+1 ,h>d5+1 ,temp]+ & ,case ,h>d5+ ( ,/eel ,,*apt] ,,ii ,,weld+ ,,mat]ials3--,production1 ,h&l+ & ,use ( ! ,gases1 ,oxyg5 & ,acetyl5e--,weld+ ,rods--,fluxes--,supplies & ,fixtures ,,*apt] ,,iii ,,acetyl5e ,,g5]ators3--,g5]ator ,requirem5ts & ,types--,con/ruction--,c>e & ,op]ation ( ,g5]ators4 ,,*apt] ,,iv ,,weld+ ,,in/rum5ts3--,tank & ,regulat+ ,valves & ,gauges--,high1 ,l[ & ,m$ium ,pressure ,tor*es--,cutt+ ,tor*es--,acetyl5e-,air ,tor*es ,,*apt] ,v ,,oxy-,,acetyl5e ,,weld+ ,,practice3--,prep>ation ( ,"w--,tor* ,practice-- ,control ( ! ,flame--,weld+ ,v>i\s ,metals & ,alloys--,tables ( ,in=mation ,requir$ 9 ,weld+ ,op]ations ,,*apt] ,,vi ,,electric ,,weld+3--,resi/ance ,me?od--,butt1 ,spot & ,lap ,weld+--,tr\bles & ,rem$ies--,electric ,arc ,weld+ ,,*apt] ,,vii ,,h& ,,=g+ ,,& ,,weld+3--,blacksmi?+1 ,=g+ & ,b5d+--,=ge ,weld+ ,me?ods ,,*apt] ,,viii ,,sold]+1 ,,braz+ ,,& ,,!rmit ,,weld+3--,sold]+ ,mat]ials & ,practice-- ,braz+--,!rmit ,weld+ ,,*apt] ,,ix ,,oxyg5 ,,process ,,= ,,removal ,,( ,,c>bon ,,index ,,oxy-,,acetyl5e ,,weld+ ,,& ,,cutt+1 ,,electric ,,& ,,!rmit ,,weld+ ,,*apt] ,i ,,metals ,,& ,,_! ,,alloys--,,heat ,,treatm5t ,,! ,,metals ,iron4--,iron1 9 its pure /ate1 is a s(t1 :ite1 easily work$ metal4 ,x is ! mo/ important ( all ! metallic elem5ts1 & is1 next to alum9um1 ! commone/ metal f\nd 9 ! e>?4 ,me*anically speak+1 we h ?ree k9ds ( iron3 wr\ght iron1 ca/ iron & /eel4 ,wr\ght iron is v ne>ly pure iron2 ca/ iron conta9s c>bon & silicon1 also *emical impurities2 & /eel conta9s a def9ite proportion ( c>bon1 b 9 small] quantities ?an ca/ iron4 ,pure iron is nev] obta9$ comm]cially1 ! metal always be+ mix$ ) v>i\s proportions ( c>bon1 silicon1 sulphur1 phosphorus1 & o!r elem5ts1 mak+ x m or less suitable = diff]5t purposes4 ,iron is magnetic to ! ext5t t x is attract$ by magnets1 b x does n reta9 magnetism itself1 z does /eel4 ,iron =ms1 ) o!r elem5ts1 _m important comb9ations1 su* z its alloys1 oxides1 & sulphates4 ,illu/ration3 ,figure #a4--,section ,?r\gh a ,bla/ ,furnace ,ca/ ,iron4--,metallic iron is sep>at$ f iron ore 9 ! bla/ furnace 7,figure #a71 & :5 all[$ to run into m\lds is call$ ca/ iron4 ,?is =m is us$ = eng9e cyl9d]s & pi/ons1 = brackets1 cov]s1 h\s+s & at any po9t :]e its brittl5ess is n objectionable4 ,good ca/ iron breaks ) a gray fracture1 is free f bl[holes or r\ghness1 & is easily ma*9$1 drill$1 etc4 ,ca/ iron is slightly light] ?an /eel1 melts at ab\t #b1djj degrees 9 practice1 is ab\t "o-eigh? z good an electrical conductor z copp] & has a t5sile /r5g? ( #ac1jjj to #cj1jjj p\nds p] squ>e in*4 ,its compressive /r5g?1 or resi/ance to cru%+1 is v great4 ,x has excell5t we>+ qualities & is n easily w>p$ & de=m$ by heat4 ,*ill$ iron is ca/ into a metal m\ld s t ! outside is cool$ quickly1 mak+ ! surface v h>d & difficult to cut & giv+ great resi/ance to we>4 ,x is us$ = mak+ *eap ge> :eels & p>ts t mu/ )/& surface friction4 ,malleable ,ca/ ,iron4--,?is is (t5 call$ simply malleable iron4 ,x is a =m ( ca/ iron obta9$ by remov+ mu* ( ! c>bon f ca/ iron1 mak+ x s(t] & less brittle4 ,x has a t5sile /r5g? ( #be1jjj to #de1jjj p\nds p] squ>e in*1 is easily ma*9$1 w /& a small am\nt ( b5d+ at a l[ r$ heat & is us$ *iefly 9 mak+ brackets1 fitt+s & supports :]e l[ co/ is ( consid]able importance4 ,x is (t5 us$ 9 *eap con/ructions 9 place ( /eel =g+s4 ,! greate/ /r5g? ( a malleable ca/+1 l a /eel =g+1 is 9 ! surface1 !re=e b little ma*9+ %\ld be done4 ,wr\ght ,iron4--,?is grade is made by treat+ ! ca/ iron to remove almo/ all ( ! c>bon1 silicon1 phosphorus1 sulphur1 manganese & o!r impurities4 ,?is process leaves a small am\nt ( ! slag f ! ore mix$ ) ! wr\ght iron4 ,wr\ght iron is us$ = mak+ b>s to be ma*9$ into v>i\s p>ts4 ,if drawn ?r\gh ! rolls at ! mill once1 :ile be+ made1 x is call$ muck b>2 if roll$ twice1 x is call$ m]*ant b> 7! commone/ k9d71 & a /ill bett] grade is made by roll+ a ?ird "t4 ,wr\ght iron is be+ gradually replac$ 9 use by mild roll$ /eels4 ,wr\ght iron is slightly heavi] ?an ca/ iron1 is a mu* bett] electrical conductor ?an ei!r ca/ iron or /eel1 has a t5sile /r5g? ( #dj1jjj to #fj1jjj p\nds p] squ>e in* & co/s slightly m ?an /eel4 ,unlike ei!r /eel or ca/ iron1 wr\ght iron does n h>d5 :5 cool$ sudd5ly f a r$ heat4 ,grades ( ,irons4--,! me*anical prop]ties ( ca/ iron diff] greatly accord+ to ! am\nt ( o!r mat]ials x conta9s4 ,! mo/ important ( ^! conta9$ elem5ts is c>bon1 :i* is pres5t to a degree v>y+ f #b to #e-a_/b p] c5t4 ,:5 iron conta9+ mu* c>bon is quickly cool$ & !n brok51 ! fracture is ne>ly :ite 9 color & ! metal is f\nd to be h>d & brittle4 ,:5 ! iron is sl[ly cool$ & !n brok5 ! fracture is gray & ! iron is m malleable & less brittle4 ,if ca/ iron conta9s sulphur or phosphorus1 x w %[ a :ite fracture reg>dless ( ! rapidity ( cool+1 be+ brittle & less desirable = g5]al "w4 ,/eel4--,/eel is compos$ ( extremely m9ute p>ticles ( iron & c>bon1 =m+ a network ( lay]s & b&s4 ,?is c>bon is a small] proportion ( ! metal ?an f\nd 9 ca/ iron1 ! p]c5tage be+ f #c_/aj to #b-a_/b p] c5t4 ,c>bon /eel is specifi$ accord+ to ! numb] ( po9ts ( c>bon1 a po9t be+ "o "o-hundr$? ( "o p] c5t ( ! weight ( ! /eel4 ,/eel may conta9 any:]e f #cj to #bej po9ts1 :i* is equival5t to say+1 any:]e f #c_/aj to #b-a_/b p] c5t1 z above4 ,a #gj-po9t /eel w\ld conta9 #gj_/ajj ( "o p] c5t or #g_/aj ( "o p] c5t ( c>bon by weight4 ,! p]c5tage ( c>bon det]m9es ! h>dness ( ! /eel1 also _m o!r qualities1 & its suitability = v>i\s k9ds ( "w4 ,! m c>bon conta9$ 9 ! /eel1 ! h>d] ! metal w be1 &1 ( c\rse1 its brittl5ess increases ) ! h>dness4 ,! small] ! gra9s or p>ticles ( iron :i* are sep>at$ by ! c>bon1 ! /rong] ! /eel w be1 & ! control ( ! size ( ^! p>ticles is ! object ( ! sci5ce ( heat treatm5t4 ,9 addition to ! c>bon1 /eel may conta9 ! foll[+3 ,silicon1 :i* increases ! h>dness1 brittl5ess1 /r5g? & difficulty ( work+ if f #b to #c p] c5t is pres5t4 ,phosphorus1 :i* h>d5s & weak5s ! metal b makes x easi] to ca/4 ,?ree-t5?s p] c5t ( phosphorus s]ves z a h>d5+ ag5t & may be pres5t 9 good /eel if ! p]c5tage ( c>bon is l[4 ,m ?an ?is weak5s ! metal4 ,sulphur1 :i* t5ds to make ! metal h>d & fill$ ) small holes4 ,manganese1 :i* makes ! /eel s h>d & t\gh t x c ) difficulty be cut ) /eel tools4 ,its h>dness is n less5$ by anneal+1 & x has great t5sile /r5g?4 ,alloy /eel has a v>y+ b small p]c5tage ( o!r elem5ts mix$ ) x to give c]ta9 desir$ qualities4 ,silicon /eel & manganese /eel are sometimes class$ z alloy /eels4 ,?is subject is tak5 up 9 ! latt] "p ( ?is *apt] "u ,alloys1 :]e ! v>i\s comb9ations & _! *>act]i/ics are giv5 consid]ation4 ,/eel has a t5sile /r5g? v>y+ f #ej1jjj to #cjj1jjj p\nds p] squ>e in*1 dep5d+ on ! c>bon p]c5tage & ! o!r alloys pres5t1 z well z ^u ! texture ( ! gra94 ,/eel is heavi] ?an ca/ iron & weighs ab\t ! same z wr\ght iron4 ,x is ab\t "o-n9? z good a conductor ( electricity z copp]4 ,/eel is made f ca/ iron by ?ree pr9cipal processes3 ! crucible1 ,bessem] & op5 he>?4 ,crucible /eel is made by plac+ pieces ( iron 9 a clay or graphite crucible1 mix$ ) *>coal & a small am\nt ( any desir$ alloy4 ,! crucible is !n heat$ ) coal1 oil or gas fires until ! iron melts1 &1 by absorb+ ! desir$ elem5ts & giv+ up or *ang+ its p]c5tage ( c>bon1 becomes /eel4 ,! molt5 /eel is !n p\r$ f ! crucible into m\lds or b>s = use4 ,crucible /eel may also be made by plac+ crude /eel 9 ! crucibles 9 place ( ! iron4 ,?is la/ me?od gives ! f9e/ grade ( metal & ! crucible process 9 g5]al gives ! be/ grades ( /eel = me*anical use4 ,illu/ration3 ,figure #b4--;,a ,bessem] ,conv]t] ,bessem] /eel is made by heat+ iron until all ! undesirable elem5ts are burn$ out by air bla/s :i* furni% ! necess>y oxyg54 ,! iron is plac$ 9 a l>ge retort call$ a conv]t]1 be+ p\r$1 :ile at a melt+ heat1 directly f ! bla/ furnace into ! conv]t]4 ,:ile ! iron 9 ! conv]t] is molt51 bla/s ( air are =c$ ?r\gh ! liquid1 mak+ x /ill hott] & burn+ out ! impurities toge!r ) ! c>bon & manganese4 ,^! two elem5ts are !n re/or$ to ! iron by add+ spiegeleis5 7an alloy ( iron1 c>bon & manganese74 ,a conv]t] holds f #e to #be tons ( metal & requires ab\t #bj m9utes to f9i% a *>ge4 ,?is makes ! *eape/ /eel4 ,illu/ration3 ,figure #c4--;,an ,op5 ,he>? ,furnace ,op5 he>? /eel is made by plac+ ! molt5 iron 9 a receptacle :ile curr5ts ( air pass ov] x1 ?is air hav+ itself be5 highly heat$ by j pass+ ov] :ite hot brick 7,figure4 #c74 ,op5 he>? /eel is consid]$ m uni=m & reliable ?an ,bessem]1 & is us$ = spr+s1 b> /eel1 tool /eel1 /eel plates1 etc4 ,alum9um is "o ( ! commone/ indu/rial metals4 ,x is us$ = ge> cases1 eng9e crank cases1 cov]s1 fitt+s1 & :]ev] lightness & mod]ate /r5g? are desirable4 ,alum9um is ab\t "o-?ird ! weight ( iron & ab\t ! same weight z glass & porcela92 x is a good electrical conductor 7ab\t "o-half z good z copp]72 is fairly /rong itself & gives great /r5g? to o!r metals :5 alloy$ ) !m4 ,"o ( ! greate/ advantages ( alum9um is t x w n ru/ or corrode "u ord9>y conditions4 ,! granul> =mation ( alum9um makes its /r5g? v unreliable & x is too s(t to resi/ we>4 ,copp] is "o ( ! mo/ important metals us$ 9 ! trades1 & ! be/ comm]cial conductor ( electricity1 be+ exce$$ 9 ?is respect only by silv]1 :i* is b slightly bett]4 ,copp] is v malleable & ductile :5 cold1 & 9 ?is /ate may be easily work$ "u ! hamm]4 ,work+ 9 ?is way makes ! copp] /rong] & h>d]1 b less ductile4 ,copp] is n affect$ by air1 b acids cause ! =mation ( a gre5 deposit call$ v]digris4 ,copp] is "o ( ! be/ conductors ( heat1 z well z electricity1 be+ us$ = kettles1 boil]s1 /ills & :]ev] ?is quality is desirable4 ,copp] is also us$ 9 alloys ) o!r metals1 =m+ an important "p ( brass1 bronze1 g]man silv]1 bell metal & gun metal4 ,x is ab\t "o-eigh? heavi] ?an /eel & has a t5sile /r5g? ( ab\t #be1jjj to #ej1jjj p\nds p] squ>e in*4 ,lead4--,! peculi> prop]ties ( lead1 & especially its quality ( %[+ b little action or *emical *ange 9 ! pres5ce ( o!r elem5ts1 makes x valuable "u c]ta9 conditions ( use4 ,its pr9cipal use is 9 pipes = wat] & gas1 cov]+s = ro(s & l9+s = vats & tanks4 ,x is also us$ to coat %eet iron = simil> uses & z an important "p ( ord9>y sold]4 ,lead is ! s(te/ & weake/ ( all ! comm]cial metals1 be+ v pliable & inela/ic4 ,x %\ld be rememb]$ t lead & all its comp\nds are poison\s :5 receiv$ into ! sy/em4 ,lead is m ?an "o-?ird heavi] ?an /eel1 has a t5sile /r5g? ( only ab\t #b1jjj p\nds p] squ>e in*1 & is only ab\t "o-t5? z good a conductor ( electricity z copp]4 ,z9c4--,?is is a blui%-:ite metal ( cry/all9e =m4 ,x is brittle at ord9>y temp]atures & becomes malleable at ab\t #bej to #cjj degrees ,fahr5heit1 b beyond ?is po9t becomes ev5 m brittle ?an at ord9>y temp]atures4 ,z9c is practically unaffect$ by air or moi/ure ?r\gh becom+ cov]$ ) "o ( its own comp\nds :i* imm$iately resi/s fur!r action4 ,z9c melts at l[ temp]atures1 & :5 heat$ beyond ! melt+ po9t gives (f v poison\s fumes4 ,! pr9cipal use ( z9c is z an alloy ) o!r metals to =m brass1 bronze1 g]man silv] & be>+ metals4 ,x is also us$ to cov] ! surface ( /eel & iron plates1 ! plates be+ !n call$ galvaniz$4 ,z9c weighs slightly less ?an /eel1 has a t5sile /r5g? ( #e1jjj p\nds p] squ>e in*1 & is n q half z good z copp] 9 conduct+ electricity4 ,t9 resembles silv] 9 color & lu/]4 ,t9 is ductile & malleable & slightly cry/all9e 9 =m1 almo/ z heavy z /eel1 & has a t5sile /r5g? ( #d1ejj p\nds p] squ>e in*4 ,! pr9cipal use ( t9 is = protective plat+s on h\sehold ut5sils & 9 wrapp+s ( t9-foil4 ,t9 =ms an important "p ( _m alloys su* z babbitt1 ,britannia metal1 bronze1 gun metal & be>+ metals4 ,nickel is important 9 me*anics because ( its comb9ations ) o!r metals z alloys4 ,pure nickel is grayi%-:ite1 malleable1 ductile & t5aci\s4 ,x weighs almo/ z mu* z /eel &1 next to manganese1 is ! h>de/ ( metals4 ,nickel is "o ( ! ?ree magnetic metals1 ! o!rs be+ iron & cobalt4 ,! commone/ alloy conta9+ nickel is g]man silv]1 al?\gh "o ( its mo/ important alloys is f\nd 9 nickel /eel4 ,nickel is ab\t t5 p] c5t heavi] ?an /eel1 & has a t5sile /r5g? ( #ij1jjj p\nds p] squ>e in*4 ,plat9um4--,?is metal is valuable = two reasons3 x is n affect$ by ! air or moi/ure or any ord9>y acid or salt1 & 9 addition to ?is prop]ty x melts only at ! highe/ temp]atures4 ,x is a fairly good electrical conductor1 be+ bett] ?an iron or /eel4 ,x is ne>ly ?ree times z heavy z /eel & its t5sile /r5g? is #be1jjj p\nds p] squ>e in*4 ,,alloys ,an alloy is =m$ by ! union ( a metal ) "s o!r mat]ial1 ei!r metal or non-metallic1 ?is union be+ compos$ ( two or m elem5ts & usually br\ght ab\t by heat+ ! sub/ances toge!r until !y melt & unite4 ,metals are alloy$ ) mat]ials :i* h be5 f\nd to give to ! metal c]ta9 *>act]i/ics :i* are desir$ accord+ to ! use ! metal w be put to4 ,! alloys ( metals are1 almo/ )\t exception1 m important f an indu/rial /&po9t ?an ! metals !mselves4 ,!re are innum]able possible comb9ations1 ! mo/ useful ( :i* are "h class$ "u ! head ( ! pr9cipal metal ent]+ into _! composition4 ,/eel4--,/eel may be alloy$ ) almo/ any ( ! metals or elem5ts1 ! comb9ations t h prov5 valuable numb]+ m ?an a score4 ,! pr9cipal ones are giv5 9 alphabetical ord]1 z foll[s3 ,alum9um is add$ to /eel 9 v small am\nts = ! purpose ( prev5t+ bl[ holes 9 ca/+s4 ,boron increases ! d5sity & t\ghness ( ! metal4 ,bronze1 add$ by alloy+ copp]1 t9 & iron1 is us$ = gun metal4 ,c>bon has already be5 consid]$ "u ! head ( /eel 9 ! section devot$ to ! metals4 ,c>bon1 :ile increas+ ! /r5g? & h>dness1 decreases ! ease ( =g+ & b5d+ & decreases ! magnetism & electrical conductivity4 ,high c>bon /eel c be weld$ only ) difficulty4 ,:5 ! p]c5tage ( c>bon is l[1 ! /eel is call$ l[ c>bon or mild /eel4 ,?is is us$ = rods & %afts1 & call$ ma*9e /eel4 ,:5 ! c>bon p]c5tage is high1 ! /eel is call$ high c>bon /eel1 & x is us$ 9 ! %op z tool /eel4 ,"o-t5? p] c5t ( c>bon gives /eel a t5sile /r5g? ( #ej1jjj to #fe1jjj p\nds p] squ>e in*2 two-t5?s p] c5t gives f #fj1jjj to #hj1jjj2 f\r-t5?s p] c5t gives #gj1jjj to #ajj1jjj1 & six-t5?s p] c5t gives #ij1jjj to #abj1jjj4 ,*romium =ms *rome /eel1 & ) ! fur!r addition ( nickel is call$ *rome nickel /eel4 ,?is increases ! h>dness to a high degree & adds /r5g? )\t mu* decrease 9 ductility4 ,*rome /eels are us$ = high-spe$ cutt+ tools1 armor plate1 files1 spr+s1 safes1 dies1 etc4 ,manganese has be5 m5tion$ "u ,/eel4 ,its alloy is mu* us$ = high-spe$ cutt+ tools1 ! /eel h>d5+ :5 cool$ 9 ! air & be+ call$ self-h>d5+4 ,molybd5um is us$ to increase ! h>dness to a high degree & makes ! /eel suitable = high-spe$ cutt+ & gives x self-h>d5+ prop]ties4 ,nickel1 ) :i* is (t5 comb9$ *romium1 increases ! /r5g?1 spr+9ess & t\ghness & helps to prev5t corrosion4 ,silicon has already be5 describ$4 ,x suits ! metal = use 9 high-spe$ tools4 ,silv] add$ to /eel has _m ( ! prop]ties ( nickel4 ,tung/5 increases ! h>dness )\t mak+ ! /eel brittle4 ,?is makes ! /eel well suit$ = gas eng9e valves z x resi/s corrosion & pitt+4 ,*romium & manganese are (t5 us$ 9 comb9ation ) tung/5 :5 high-spe$ cutt+ tools are made4 ,vanadium z an alloy increases ! ela/ic limit1 mak+ ! /eel /rong]1 t\gh] & h>d]4 ,x also makes ! /eel able to /& mu* b5d+ & vibration4 ,copp]4--,! pr9cipal copp] alloys include brass1 bronze1 g]man silv] & gun metal4 ,brass is compos$ ( approximately "o-?ird z9c & two-?irds copp]4 ,x is us$ = be>+s & bu%+s :]e ! spe$s are sl[ & ! loads r heavy = ! be>+ size4 ,x also f9ds use 9 wa%]s1 coll>s & =ms ( brackets :]e ! metal %\ld be non-magnetic1 also = _m highly f9i%$ p>ts4 ,brass is ab\t "o-?ird z good an electrical conductor z copp]1 is slightly heavi] ?an /eel & has a t5sile /r5g? ( #ae1jjj p\nds :5 ca/ & ab\t #ge1jjj to #ajj1jjj p\nds :5 drawn into wire4 ,bronze is compos$ ( copp] & t9 9 v>i\s proportions1 accord+ to ! use to :i* x is to be put4 ,!re w always be f six-t5?s to n9e-t5?s ( copp] 9 ! mixture4 ,bronze is us$ = be>+s1 bu%+s1 ?ru/ wa%]s1 brackets & ge> :eels4 ,x is heavi] ?an /eel1 ab\t #a_/ae z good an electrical conductor z pure copp] & has a t5sile /r5g? ( #cj1jjj to #fj1jjj p\nds4 ,alum9um bronze1 compos$ ( copp]1 z9c & alum9um has high t5sile /r5g? comb9$ ) ductility & is us$ = p>ts requir+ ?is comb9ation4 ,be>+ bronze is a v>iable mat]ial1 its composition & proportion dep5d+ on ! mak] & ! use = :i* x is design$4 ,x usually conta9s f #ge to #he p] c5t ( copp] comb9$ ) "o or m elem5ts1 su* z t91 z9c1 antimony & lead4 ,:ite metal is "o =m ( be>+ bronze conta9+ ov] #hj p] c5t ( z9c toge!r ) copp]1 t91 antimony & lead4 ,ano!r =m is made ) ne>ly #ij p] c5t ( t9 comb9$ ) copp] & antimony4 ,gun metal bronze is made f #ij p] c5t copp] ) #aj p] c5t ( t9 & is us$ = heavy be>+s1 brackets & highly f9i%$ p>ts4 ,phosphor bronze is us$ = v /rong ca/+s & be>+s4 ,x is simil> to gun metal bronze1 except t ab\t #a-a_/b p] c5t ( phosphorus has be5 add$4 ,manganese bronze conta9s ab\t #a p] c5t ( manganese & is us$ = p>ts requir+ great /r5g? :ile be+ free f corrosion4 ,g]man silv] is made f #fj p] c5t ( copp] ) #bj p] c5t ea* ( z9c & nickel4 ,its high electrical resi/ance makes x valuable = regulat+ devices & rheo/ats4 ,t9 is ! pr9cipal "p ( babbitt & sold]4 ,a commonly us$ babbitt is compos$ ( #hi p] c5t t91 #h p] c5t antimony & #c p] c5t ( copp]4 ,a grade suitable = repair+ is made f #hj p] c5t ( lead & #bj p] c5t antimony4 ,?is la/ =mula %\ld n be us$ = p>ticul> "w or heavy loads1 be+ m suitable = spac]s4 ,innum]able proportions ( metals are m>ket$ "u ! "n ( babbitt4 ,sold] is made f #ej p] c5t t9 & #ej p] c5t lead1 ?is grade be+ call$ half-&-half4 ,h>d sold] is made f two-?irds t9 & "o-?ird lead4 ,alum9um =ms _m diff]5t alloys1 giv+ increas$ /r5g? to :atev] metal x unites )4 ,alum9um brass is compos$ ( approximately #fe p] c5t copp]1 #cj p] c5t z9c & #e p] c5t alum9um4 ,x =ms a metal ) high t5sile /r5g? :ile be+ ductile & malleable4 ,alum9um z9c is suitable = ca/+s :i* mu/ be /iff & h>d4 ,nickel alum9um has a t5sile /r5g? ( #dj1jjj p\nds p] squ>e in*4 ,magnalium is a silv]-:ite alloy ( alum9um ) f #e to #bj p] c5t ( magnesium1 =m+ a metal ev5 light] ?an alum9um & /rong en\gh to be us$ 9 mak+ high-spe$ gasol9e eng9es4 ,,heat ,,treatm5t ,,( ,,/eel ,! processes ( heat treatm5t are design$ to suit ! /eel = v>i\s purposes by *ang+ ! size ( ! gra9 9 ! metal1 !re=e ! /r5g?2 & by alt]+ ! *emical composition ( ! alloys 9 ! metal to give x diff]5t physical prop]ties4 ,heat treatm5t1 z appli$ 9 ord9>y %op "w1 includes ! ?ree processes ( anneal+1 h>d5+ & temp]+1 ea* design$ to accompli% a c]ta9 def9ite result4 ,all ( ^! processes require t ! metal treat$ be gradually br\ght to a c]ta9 pr$et]m9$ degree ( heat :i* %all be uni=m ?r\gh\t ! piece be+ h&l$ &1 f ?is po9t1 cool$ accord+ to c]ta9 rules1 ! selection ( :i* =ms ! diff]5ce 9 ! ?ree me?ods4 ,anneal+4--,?is is ! process :i* relieves all int]nal /ra9s & di/ortion 9 ! metal & s(t5s x s t x may m easily be cut1 ma*9$ or b5t to ! requir$ =m4 ,9 "s cases anneal+ is us$ only to relieve ! /ra9s1 ?is be+ ! case aft] =g+ or weld+ op]ations h be5 p]=m$4 ,9 o!r cases x is only desir$ to s(t5 ! metal suffici5tly t x may be h&l$ easily4 ,9 "s cases bo? ( ^! ?+s mu/ be accompli%$1 z aft] a piece has be5 =g$ & mu/ be ma*9$4 ,no matt] :at ! object1 ! proc$ure is ! same4 ,! /eel to be anneal$ mu/ fir/ be heat$ to a dull r$4 ,?is heat+ %\ld be done sl[ly s t all p>ts ( ! piece h "t to rea* ! same temp]ature at v ne>ly ! same "t4 ,! piece may be heat$ 9 ! =ge1 b a mu* bett] way is to heat 9 an ov5 or furnace ( "s type :]e ! "w is protect$ aga9/ air curr5ts1 ei!r hot or cold1 & is also protect$ aga9/ ! direct action ( ! fire4 ,illu/ration3 ,figure #d4--;,a ,gaspipe ,anneal+ ,ov5 ,probably ! simple/ ( all ov5s = small tools is made by plac+ a piece ( ord9>y gas pipe 9 ! fire 7,figure #d71 & heat+ until ! inside ( ! pipe is bright r$4 ,p>ts plac$ 9 ?is pipe1 aft] "o end has be5 clos$1 may be br\ght to ! desir$ heat )\t dang] ( cool+ draughts or *emical *ange f ! action ( ! fire4 ,m elaborate ov5s may be b\ght :i* use gas1 fuel oils or coal to produce ! heat & 9 :i* ! "w may be plac$ on trays s t ! fire w n /rike directly on ! /eel be+ treat$4 ,if ! "w is n v important1 x may be )drawn f ! fire or ov51 aft] heat+ to ! desir$ po9t1 & all[$ to cool 9 ! air until all traces ( r$ h disappe>$ :5 held 9 a d>k place4 ,! "w %\ld be held :]e x is reasonably free f cold air curr5ts4 ,if1 ^u t\*+ a p9e /ick to ! piece be+ anneal$1 ! wood does n smoke1 ! "w may !n be cool$ 9 wat]4 ,bett] anneal+ is secur$ & h>d] metal may be anneal$ if ! cool+ is ext5d$ ov] a numb] ( h\rs by plac+ ! "w 9 a b$ ( non-heat-conduct+ mat]ial1 su* z a%es1 *>r$ bone1 asbe/os fibre1 lime1 s& or fire clay4 ,x %\ld be well cov]$ ) ! heat reta9+ mat]ial & all[$ to rema9 until cool4 ,cool+ may be accompli%$ by all[+ ! fire 9 an ov5 or furnace to die d[n & g out1 leav+ ! "w inside ! ov5 ) all op5+s clos$4 ,! great] ! "t tak5 = gradual cool+ f ! r$ heat1 ! m p]fect w be ! results ( ! anneal+4 ,:ile /eel is anneal$ by sl[ cool+1 copp] or brass is anneal$ by br++ to a l[ r$ heat & quickly plung+ into cold wat]4 ,h>d5+4--,/eel is h>d5$ by br++ to a prop] temp]ature1 sl[ly & ev5ly z = anneal+1 & !n cool+ m or less quickly1 accord+ to ! grade ( /eel be+ h&l$4 ,! degree ( h>d5+ is det]m9$ by ! k9d ( /eel1 ! temp]ature f :i* ! metal is cool$ & ! temp]ature & nature ( ! ba? into :i* x is plung$ = cool+4 ,/eel to be h>d5$ is (t5 heat$ 9 ! fire until at "s heat ar\nd #fjj to #gjj degrees is rea*$1 !n plac$ 9 a heat+ ba? ( molt5 lead1 heat$ m]cury1 fus$ cyanate ( potassium1 etc41 ! heat+ ba? itself be+ kept at ! prop] temp]ature by fires act+ on x4 ,:ile ^! ba?s h ! advantage ( heat+ ! metal ev5ly & to exactly ! temp]ature desir$ ?r\gh\t )\t any "p becom+ ov] or "u heat$1 _! disadvantages consi/ ( ! fact t _! mat]ials & ! fumes are poison\s 9 mo/ all cases1 & if n poison\s1 are extremely disagreeable4 ,! degree ( heat t a piece ( /eel mu/ be br\ght to 9 ord] t x may be h>d5$ dep5ds on ! p]c5tage ( c>bon 9 ! /eel4 ,! great] ! p]c5tage ( c>bon1 ! l[] ! heat necess>y to h>d54 ,illu/ration3 ,figure #e4--;,cool+ ! ,te/ ,b> = ,h>d5+ ,to f9d ! prop] heat f :i* any /eel mu/ be cool$1 a simple te/ may be c>ri$ out provid$ a sample ( ! /eel1 ab\t six in*es long c be secur$4 ,"o end ( ?is te/ b> %\ld be heat$ almo/ to its melt+ po9t1 & held at ?is heat until ! o!r end j turns r$4 ,n[ cool ! piece 9 wat] by plung+ x s t bo? ends ent] at ! same "t 7,figure #e71 t is1 hold x p>allel ) ! surface ( ! wat] :5 plung$ 94 ,?is s]ves ! purpose ( cool+ ea* po9t along ! b> f a diff]5t heat4 ,:5 x has cool$ 9 ! wat] remove ! piece & break x at %ort int]vals1 ab\t #a_/b in*1 along its l5g?4 ,! po9t along ! te/ b> :i* 0 cool$ f ! be/ possible temp]ature w %[ a v f9e smoo? gra9 & ! piece _c be cut by a file at ?is po9t4 ,x w be necess>y to rememb] ! exact color ( t po9t :5 tak5 f ! fire1 mak+ ano!r te/ if necess>y1 & heat all pieces ( ?is same /eel to ?is heat4 ,x w be necess>y to h ! cool+ ba? always at ! same temp]ature1 or ! results _c be alike4 ,:ile /eel to be h>d5$ is usually cool$ 9 wat]1 _m o!r liquids may be us$4 ,if cool$ 9 /rong br9e1 ! heat w be extract$ mu* quick]1 & ! degree ( h>dness w be great]4 ,a /ill great] degree ( h>dness is secur$ by cool+ 9 a ba? ( m]cury4 ,c>e %\ld be us$ ) ! m]cury ba?1 z ! fumes t arise are poison\s4 ,%\ld t\ghness be desir$1 )\t extreme h>dness1 ! /eel may be cool$ 9 a ba? ( l>d oil1 neatsfoot oil or fi% oil4 ,to secure a result betwe5 wat] & oil1 x is cu/om>y to place a ?ick lay] ( oil on top ( wat]4 ,9 cool+1 ! piece w pass ?r\gh ! oil fir/1 ?us avoid+ ! sudd5 %ock ( ! cold wat]1 yet produc+ a degree ( h>dness almo/ z great z if ! oil 7 n us$4 ,x w1 ( c\rse1 be necess>y to make a sep>ate te/ = ea* cool+ m$ium us$4 ,if ! fracture ( ! te/ piece %[s a co>se gra91 ! /eel 0 too hot at t po9t2 if ! fracture c be cut ) a file1 ! metal 0 n hot en\gh at t po9t4 ,:5 h>d5+ c>bon tool /eel its heat %\ld be br\ght to a *]ry r$1 ! exact degree ( heat dep5d+ on ! am\nt ( c>bon & ! te/ made1 !n plung$ into wat] & held !re until all hiss+ s\nd & vibration ceases4 ,br9e may be us$ = ?is purpose2 x is ev5 bett] ?an pla9 wat]4 ,z soon z ! hiss+ /ops1 remove ! "w f ! wat] or br9e & plunge 9 oil = complete cool+4 ,illu/ration3 ,figure #f4--;,cool+ ! ,tool = ,temp]+ ,9 h>d5+ high-spe$ tool /eel1 or air h>d5+ /eels1 ! tool %\ld be h&l$ z = c>bon /eel1 except t aft] ! body rea*es a *]ry r$1 ! cutt+ po9t mu/ be quickly br\ght to a :ite heat1 almo/ melt+1 s t x seems ready = weld+4 ,!n cool 9 an oil ba? or 9 a curr5t ( cool air4 ,h>d5+ ( copp]1 brass & bronze is accompli%$ by hamm]+ or work+ !m :ile cold4 ,temp]+ is ! process ( mak+ /eel t\gh aft] x has be5 h>d5$1 s t x w hold a cutt+ edge & resi/ crack+4 ,temp]+ makes ! gra9 f9] & ! metal /rong]4 ,x does n affect ! h>dness1 b increases ! ela/ic limit & r$uces ! brittl5ess ( ! /eel4 ,9 t temp]+ is usually p]=m$ imm$iately aft] h>d5+1 x might be consid]$ z a cont9uation ( ! =m] process4 ,! "w or tool to be temp]$ is sl[ly heat$ to a *]ry r$ & ! cutt+ end is !n dipp$ into wat] to a dep? ( #a_/b to #c_/d in* above ! po9t 7,figure #f74 ,z soon z ! po9t cools1 /ill leav+ ! tool r$ above ! "p 9 wat]1 remove ! "w f ! ba? & quickly rub ! end ) a f9e em]y clo?4 ,z ! heat f ! uncool$ "p gradually heats ! po9t aga91 ! color ( ! poli%$ portion *anges rapidly4 ,:5 a c]ta9 color is rea*$1 ! tool %\ld be completely imm]s$ 9 ! wat] until cold4 ,= la!1 plan]1 %ap] & slott] tools1 ?is color %\ld be a light /raw4 ,ream]s & taps %\ld be cool$ f an ord9>y /raw color4 ,drills1 pun*es & wood work+ tools %\ld h a br[n color4 ,blue or light purple is "r = cold *isels & screwdriv]s4 ,d>k blue %\ld be rea*$ = spr+s & wood saws4 ,d>k] colors ?an ?is1 rang+ ?r\gh gre5 & gray1 d5ote t ! piece has rea*$ its ord9>y temp]1 t is1 x is p>tially anneal$4 ,aft] prop]ly h>d5+ a spr+ by dipp+ 9 l>d or fi% oil1 x %\ld be held ov] a fire :ile /ill wet ) ! oil4 ,! oil takes fire & burns (f1 prop]ly temp]+ ! spr+4 ,rememb] t self-h>d5+ /eels mu/ nev] be dipp$ 9 wat]1 & always rememb] = all "w requir+ degrees ( heat1 t ! m c>bon1 ! less heat4 ,case ,h>d5+4--,?is is a process = add+ m c>bon to ! surface ( a piece ( /eel1 s t x w h good we>-resi/+ qualities1 :ile be+ t\gh & /rong on ! inside4 ,x has ! effect ( =m+ a v h>d & durable sk9 on ! surface ( s(t /eel1 leav+ ! inside unaffect$4 ,! simple/ way1 al?\gh n ! mo/ effici5t1 is to heat ! piece to be case h>d5$ to a r$ heat & !n spr9kle or rub ! "p ( ! surface to be h>d5$ ) potassium f]rocyanide4 ,?is mat]ial is a deadly poison & %\ld be h&l$ ) c>e4 ,all[ ! cyanide to fuse on ! surface ( ! metal & !n plunge into wat]1 br9e or m]cury4 ,repeat+ ! process makes ! surface h>d] & ! h>d sk9 deep] ea* "t4 ,ano!r me?od consi/s ( plac+ ! piece to be h>d5$ 9 a b$ ( p[d]$ bone 7bone :i* has be5 burn$ & !n p[d]$7 & cov] ) m p[d]$ bone1 hold+ ! :ole 9 an iron tray4 ,n[ heat ! tray & bone ) ! "w 9 an ov5 to a bright r$ heat = #cj m9utes to an h\r & !n plunge ! "w into wat] or br9e4 ,,*apt] ,,ii ,,oxy-,,acetyl5e ,,weld+ ,,& ,,cutt+ ,,mat]ials ,weld+4--,oxy-acetyl5e weld+ is an autog5\s weld+ process1 9 :i* two p>ts ( ! same or diff]5t metals are jo9$ by caus+ ! edges to melt & unite :ile molt5 )\t ! aid ( hamm]+ or compression4 ,:5 cool1 ! p>ts =m "o piece ( metal4 ,! oxy-acetyl5e flame is made by mix+ oxyg5 & acetyl5e gases 9 a special weld+ tor* or bl[pipe1 produc+1 :5 burn$1 a heat ( #f1cjj degrees1 :i* is m ?an twice ! melt+ temp]ature ( ! common metals4 ,?is flame1 :ile be+ ( int5se heat1 is ( v small size4 ,cutt+4--,! process ( cutt+ metals ) ! flame produc$ f oxyg5 & acetyl5e dep5ds on ! fact t a jet ( oxyg5 direct$ ^u hot metal causes ! metal itself to burn away ) great rapidity1 result+ 9 a n>r[ slot ?r\gh ! section cut4 ,! action is s fa/ t metal is n injur$ on ei!r side ( ! cut4 ,c>bon ,removal4--,?is process dep5ds on ! fact t c>bon w burn & almo/ completely vani% if ! action is assi/$ ) a supply ( pure oxyg5 gas4 ,aft] ! combu/ion is />t$ ) any conv5i5t flame1 x cont9ues z long z c>bon rema9s 9 ! pa? ( ! jet ( oxyg54 ,mat]ials4--,= ! p]=mance ( ! above op]ations we require ! two gases1 oxyg5 & acetyl5e1 to produce ! flames2 rods ( metal :i* may be add$ to ! jo9ts :ile molt5 9 ord] to give ! weld suffici5t /r5g? & prop] =m1 & v>i\s *emical p[d]s1 call$ fluxes1 :i* assi/ 9 ! fl[ ( metal & 9 do+ away ) _m ( ! impurities & o!r objectionable features4 ,in/rum5ts4--,to control ! combu/ion ( ! gases & add to ! conv5i5ce ( ! op]ator a numb] ( accessories are requir$4 ,! pressure ( ! gases 9 _! usual conta9]s is mu* too high = _! prop] use 9 ! tor* & we !re=e ne$ suitable valves :i* all[ ! gas to escape f ! conta9]s :5 want$1 & o!r specially design$ valves :i* r$uce ! pressure4 ,hose1 compos$ ( rubb] & fabric1 toge!r ) suitable connections1 is us$ to c>ry ! gas to ! tor*4 ,! tor*es = weld+ & cutt+ =m a class ( highly develop$ in/rum5ts ( ! greate/ accuracy 9 manufacture1 & mu/ be ?or\ghly und]/ood by ! weld]4 ,tables1 /&s & special supports are provid$ = hold+ ! "w :ile be+ weld$1 & 9 ord] to h&le ! v>i\s metals & all[ = _! peculi>ities :ile heat$ use is made ( ov5s & tor*es = preheat+4 ,! op]ator requires ! protection ( goggles1 masks1 gloves & appliances :i* prev5t undue radiation ( ! heat4 ,tor* ,practice4--,! actual "w ( weld+ & cutt+ requires prelim9>y prep>ation 9 ! =m ( heat treatm5t = ! metals1 includ+ preheat+1 anneal+ & temp]+4 ,! surfaces to be jo9$ mu/ be prop]ly prep>$ = ! flame1 & ! op]ation ( ! tor*es = be/ results requires c>eful & correct regulation ( ! gases & ! flame produc$4 ,f9ally1 ! diff]5t metals t are to be weld$ require special treatm5t = ea* "o1 dep5d+ on ! physical & *emical *>act]i/ics ( ! mat]ial4 ,x w ?us be se5 t ! app>5tly simple op]ations ( weld+ & cutt+ require special mat]ials1 in/rum5ts & prep>ation on ! "p ( ! op]ator & x is a prov$ fact t failures1 :i* h be5 attribut$ to ! me?od1 are really due to lack ( ^! necess>y qualifications4 ,,oxyg5 ,oxyg51 ! gas :i* supports ! rapid combu/ion ( ! acetyl5e 9 ! tor* flame1 is "o ( ! elem5ts ( ! air4 ,x is ! cause & ! active ag5t ( all combu/ion t takes place 9 ! atmosph]e4 ,oxyg5 0 fir/ discov]$ z a sep>ate gas 9 #aggd1 :5 x 0 produc$ by heat+ r$ oxide ( m]cury & 0 giv5 its pres5t "n by ! fam\s *emi/1 ,lavoisi]4 ,oxyg5 is prep>$ 9 ! laboratory by v>i\s me?ods1 ^! includ+ ! heat+ ( *loride ( lime & p]oxide ( cobalt mix$ 9 a retort1 ! heat+ ( *lorate ( pota%1 & ! sep>ation ( wat] into its elem5ts1 hydrog5 & oxyg51 by ! passage ( an electric curr5t4 ,:ile ! la/ process is us$ on a l>ge scale 9 comm]cial "w1 ! o!rs are n practical = "w o!r ?an t ( an exp]im5tal or tempor>y nature4 ,?is gas is a colorless1 odorless1 ta/eless elem5t4 ,x is sixte5 times z heavy z ! gas hydrog5 :5 measur$ by volume "u ! same temp]ature & pressure4 ,"u all ord9>y conditions oxyg5 rema9s 9 a gase\s =m1 al?\gh x turns to a liquid :5 compress$ to #d1djj p\nds to ! squ>e in* & at a temp]ature ( #bbj bel[ z]o4 ,oxyg5 unites ) almo/ e o!r elem5t1 ?is union (t5 tak+ place ) great heat & mu* light1 produc+ flame4 ,/eel & iron w burn rapidly :5 plac$ 9 ?is gas if ! combu/ion is />t$ ) a flame ( high heat play+ on ! metal4 ,if ! end ( a wire is heat$ bright r$ & quickly plung$ into a j> conta9+ ?is gas1 ! wire w burn away ) a dazzl+ light & be entirely consum$ except = ! molt5 drops t sep>ate !mselves4 ,?is prop]ty ( oxyg5 is us$ 9 oxy-acetyl5e cutt+ ( /eel4 ,! comb9ation ( oxyg5 ) o!r sub/ances does n necess>ily cause great heat1 9 fact ! comb9ation may be s sl[ & gradual t ! *ange ( temp]ature c n be notic$4 ,an example ( ?is sl[ combu/ion1 or oxidation1 is f\nd 9 ! conv]sion ( iron into ru/ z ! metal comb9es ) ! active gas4 ,! respiration ( human be+s & animals is a =m ( sl[ combu/ion & is ! s\rce ( animal heat4 ,x is a g5]al rule t ! process ( oxidation takes place ) increas+ rapidity z ! temp]ature ( ! body be+ act$ ^u rises4 ,iron & /eel at a r$ heat oxidize rapidly ) ! =mation ( a scale & possible damage to ! metal4 ,air4--,atmosph]ic air is a mixture ( oxyg5 & nitrog5 ) traces ( c>bonic acid gas & wat] vapor4 ,tw5ty-"o p] c5t ( ! air1 by volume1 is oxyg5 & ! rema9+ sev5ty-n9e p] c5t is ! inactive gas1 nitrog54 ,b = ! pres5ce ( ! nitrog51 :i* dead5s ! action ( ! o!r gas1 combu/ion w\ld take place at a de/ructive rate & be beyond human control 9 almo/ all cases4 ,^! two gases exi/ simply z a mixture to =m ! air & are n *emically comb9$4 ,x is !re=e a comp>atively simple matt] to sep>ate !m ) ! processes n[ available4 ,wat]4--,wat] is a comb9ation ( oxyg5 & hydrog51 be+ compos$ ( exactly two volumes ( hydrog5 to "o volume ( oxyg54 ,if ^! two gases be sep>at$ f ea* o!r & !n all[$ to mix 9 ^! proportions !y unite ) explosive viol5ce & =m wat]4 ,wat] itself may be sep>at$ into ! gases by any "o ( sev]al means1 "o mak+ use ( a temp]ature ( #b1bjj to br+ ab\t ?is sep>ation4 ,illu/ration3 ,figure #g4--,obta9+ ,oxyg5 by ,electrolysis ,! easie/ way to sep>ate wat] into its two p>ts is by ! process call$ electrolysis 7,figure #g74 ,wat]1 ) :i* has be5 mix$ a small quantity ( acid1 is plac$ 9 a vat ?r\gh ! walls ( :i* ent] ! plat9um tipp$ ends ( two electrical conductors1 "o positive & ! o!r negative4 ,tubes are plac$ directly above ^! wire t]m9als 9 ! vat1 "o tube be+ ov] ea* electrode & sep>at$ f ea* o!r by "s di/ance4 ,) ! passage ( an electric curr5t f "o wire t]m9al to ! o!r1 bubbles ( gas rise f ea* & pass into ! tubes4 ,! gas t comes f ! negative t]m9al is hydrog5 & t f ! positive pole is oxyg51 bo? gases be+ almo/ pure if ! "w is prop]ly conduct$4 ,?is me?od produces electrolytic oxyg5 & electrolytic hydrog54 ,! ,liquid ,air ,process4--,:ile sev]al ( ! =ego+ me?ods ( secur+ oxyg5 are successful z f> z ?is result is conc]n$1 !y are n pr(itable f a f9ancial /&po9t4 ,a process = sep>at+ oxyg5 f ! nitrog5 9 ! air has be5 br\ght to a high /ate ( p]fection & is n[ supply+ a major "p ( ?is gas = oxy-acetyl5e weld+4 ,x is kn[n z ! ,l9de process & ! gas is di/ribut$ by ! ,l9de ,air ,products ,company f its plants & w>eh\ses locat$ 9 ! l>ge cities ( ! c\ntry4 ,! air is fir/ liquefi$ by compression1 aft] :i* ! gases are sep>at$ & ! oxyg5 collect$4 ,! air is purifi$ & !n compress$ by successive /ages 9 p[]ful ma*9es design$ = ?is purpose until x rea*es a pressure ( ab\t #c1jjj p\nds to ! squ>e in*4 ,! l>ge am\nt ( heat produc$ is absorb$ by special cool]s dur+ ! process ( compression4 ,! highly compress$ air is !n dri$ & ! temp]ature fur!r r$uc$ by o!r cool]s4 ,! next po9t 9 ! sep>ation is t at :i* ! air is introduc$ into an app>atus call$ an int]*ang] & is all[$ to escape ?r\gh a valve1 caus+ x to turn to a liquid4 ,?is liquid air is spray$ onto plates & z x falls1 ! nitrog5 return to its gase\s /ate & leaves ! oxyg5 to run to ! bottom ( ! conta9]4 ,?is liquid oxyg5 is !n all[$ to return to a gas & is /or$ 9 l>ge gasomet]s or tanks4 ,! oxyg5 gas is tak5 f ! /orage tanks & compress$ to approximately #a1hjj p\nds to ! squ>e in*1 "u :i* pressure x is pass$ into /eel cyl9d]s & made ready = deliv]y to ! cu/om]4 ,?is oxyg5 is gu>ante$ to be n9ety-sev5 p] c5t pure4 ,ano!r process1 kn[n z ! ,hildebr&t process1 is com+ into use 9 ?is c\ntry4 ,x is a lat] process & is us$ 9 ,g]many to a mu* great] ext5t ?an ! ,l9de process4 ,! ,sup]ior ,oxyg5 ,co4 has secur$ ! ,am]ican rights & has e/abli%$ sev]al plants4 ,oxyg5 ,cyl9d]s4--,two sizes ( cyl9d]s are 9 use1 "o conta9+ #ajj cubic feet ( gas :5 x is at atmosph]ic pressure & ! o!r conta9+ #bej cubic feet "u simil> conditions4 ,! cyl9d]s are made f "o piece ( /eel & are )\t seams4 ,^! conta9]s are te/$ at d\ble ! pressure ( ! gas conta9$ to insure safety :ile h&l+4 ,"o hundr$ cubic feet ( oxyg5 weighs ne>ly n9e p\nds 7#h4iba71 & !re=e ! cyl9d]s w weigh practically n9e p\nds m :5 full ?an aft] empty+1 if ( ! #ajj cubic feet size4 ,! l>ge cyl9d]s weigh ab\t eighte5 & "o-qu>t] p\nds m :5 full ?an :5 empty1 mak+ approximately #bab p\nds empty & #bcj p\nds full4 ,! foll[+ table gives ! numb] ( cubic feet ( oxyg5 rema9+ 9 ! cyl9d]s accord+ to v>i\s gauge pressures f an initial pressure ( #a1hjj p\nds4 ,! am\nts giv5 are n exactly correct z ?is w\ld necessitate l5g?y calculations :i* w\ld n make great en\gh diff]5ce to affect ! practical usefulness ( ! table3 ,cyl9d] ( #ajj ,cu4 ,ft4 ,capacity at #fh ,fahr4 ,gauge ,volume ,gauge ,volume ,pressure ,rema9+ ,pressure ,rema9+ #ahjj #ajj #gjj #ci #afbj #ij #ejj #bh #addj #hj #cjj #ag #abfj #gj #ajj #f #ajhj #fj #ah #a #ijj #ej #i #a_/b ,cyl9d] ( #bej ,cu4 ,ft4 ,capacity at #fh ,fahr4 ,gauge ,volume ,gauge ,volume ,pressure ,rema9+ ,pressure ,rema9+ #ahjj #bej #gjj #ig #afbj #bbe #ejj #gj #addj #bjj #cjj #db #abfj #age #ajj #ae #ajhj #aej #ah #h #ijj #abe #i #a-a_/d ,! temp]ature ( ! cyl9d] affects ! pressure 9 a l>ge degree1 ! pressure increas+ ) a rise 9 temp]ature & fall+ ) a fall 9 temp]ature4 ,! v>iation = a #ajj cubic foot cyl9d] at v>i\s temp]atures is giv5 9 ! foll[+ tabulation3 ,at #aej ,fahr444444444444444444444444 #bjij p\nds4 ,at #ajj ,fahr444444444444444444444444 #aiab p\nds4 ,at #hj ,fahr444444444444444444444444 #ahdd p\nds4 ,at #fh ,fahr444444444444444444444444 #ahjj p\nds4 ,at #ej ,fahr444444444444444444444444 #agcf p\nds4 ,at #cb ,fahr444444444444444444444444 #afgb p\nds4 ,at #j ,fahr444444444444444444444444 #aeeh p\nds4 ,at -#aj ,fahr444444444444444444444444 #aebb p\nds4 ,*lorate ( ,pota% ,me?od4--,9 spite ( its high] co/ & ! inf]ior gas produc$1 ! *lorate ( pota% me?od ( produc+ oxyg5 is us$ to a limit$ ext5t :5 x is impossible to secure ! gas 9 cyl9d]s4 ,illu/ration3 ,figure #h4--,oxyg5 f ,*lorate ( ,pota% ,an iron retort 7,figure #h7 is arrang$ to receive ab\t fifte5 p\nds ( *lorate ( pota% mix$ ) ?ree p\nds ( manganese dioxide1 aft] :i* ! cyl9d] is clos$ ) a tight cap1 clamp$ on4 ,?is retort is c>ri$ above a burn] us+ fuel gas or o!r means ( g5]at+ heat & ?is burn] is light$ aft] ! *emical *>ge is mix$ & compress$ 9 ! tube4 ,! g5]ation ( gas comm5ces & ! oxyg5 is l$ ?r\gh wat] ba?s :i* wa% & cool x be=e /or+ 9 a tank connect$ ) ! plant4 ,f ?is tank ! gas is compress$ into portable cyl9d]s at a pressure ( ab\t #cjj p\nds to ! squ>e in* = use z requir$ 9 weld+ op]ations4 ,ea* p\nd ( *lorate ( pota% lib]ates ab\t ?ree cubic feet ( oxyg51 & tak+ ev]y?+ into consid]ation1 ! co/ ( gas produc$ 9 ?is way is sev]al times t ( ! pur] product secur$ by ! liquid air process4 ,^! *emical g5]ators are (t5times a s\rce ( great dang]1 especially :5 us$ ) or ne> ! acetyl5e gas g5]ator1 z is sometimes ! case ) *eap portable outfits4 ,_! use %\ld n be tol]at$ :5 any o!r me?od is available1 z ! dang] f accid5t alone %\ld prohibit ! practice except :5 prop]ly in/all$ & c>$ = away f o!r s\rces ( combu/ible gases4 ,,acetyl5e ,9 #ahfb a *emi/1 ,woehl]1 ann\nc$ ! discov]y ( ! prep>ation ( acetyl5e gas f calcium c>bide1 :i* he _h made by heat+ to a high temp]ature a mixture ( *>coal ) an alloy ( z9c & calcium4 ,8 product w\ld decompose wat] & yield ! gas4 ,= ne>ly ?irty ye>s ^! sub/ances 7 neglect$1 ) ! result t acetyl5e 0 practically unkn[n1 & up to #ahib an acetyl5e flame 0 se5 by v few p]sons & its possibilities 7 n dream$ (4 ,) ! developm5t ( ! mod]n electric furnace ! possibility ( calcium c>bide z a comm]cial product became kn[n4 ,9 ! above ye>1 ,?omas ,l4 ,willson1 an electrical eng9e] ( ,spray1 ,nor? ,c>ol9a1 0 exp]im5t+ 9 an attempt to prep>e metallic calcium1 = :i* purpose he employ$ an electric furnace op]at+ on a mixture ( lime & coal t> ) ab\t n9ety-five horse p[]4 ,! result 0 a molt5 mass :i* became h>d & brittle :5 cool4 ,?is app>5tly useless product 0 disc>d$ & ?r[n 9 a ne>by /ream1 :51 to ! a/oni%m5t ( onlook]s1 a l>ge volume ( gas 0 imm$iately lib]at$1 :i*1 :5 ignit$1 burn$ ) a bright & smoky flame & gave (f quantities ( soot4 ,! solid mat]ial prov$ to be calcium c>bide & ! gas acetyl5e4 ,?us1 ?r\gh ! incid5tal /udy ( a by-product1 & z ! result ( an accid5t1 ! possibilities 9 c>bide 7 made kn[n1 & 9 ! spr+ ( #ahie ! fir/ factory 9 ! _w = ! production ( ?is sub/ance 0 e/abli%$ by ! ,willson ,alum9um ,company4 ,:5 wat] & calcium c>bide are br\ght toge!r an action takes place :i* results 9 ! =mation ( acetyl5e gas & slak$ lime4 ,,c>bide ,calcium c>bide is a *emical comb9ation ( ! elem5ts c>bon & calcium1 be+ d>k br[n1 black or gray ) sometimes a blue or r$ t+e4 ,x looks l /one & w only burn :5 heat$ ) oxyg54 ,calcium c>bide may be pres]v$ = any l5g? ( "t if protect$ f ! air1 b ! ord9>y moi/ure 9 ! atmosph]e gradually affects x until no?+ rema9s b slak$ lime4 ,x always possesses a p5etrat+ odor1 :i* is n due to ! c>bide itself b to ! fact t x is be+ con/antly affect$ by moi/ure & produc+ small quantities ( acetyl5e gas4 ,?is mat]ial is n readily dissolv$ by liquids1 b if all[$ to come 9 contact ) wat]1 a decomposition takes place ) ! evolution ( l>ge quantities ( gas4 ,c>bide is n affect$ by %ock1 j>r+ or age4 ,a p\nd ( absolutely pure c>bide w yield five & "o-half cubic feet ( acetyl5e4 ,absolute purity _c be atta9$ comm]cially1 & 9 practice good c>bide w produce f f\r & "o-half to five cubic feet = ea* p\nd us$4 ,c>bide is prep>$ by fus+ lime & c>bon 9 ! electric furnace "u a heat 9 excess ( #f1jjj degrees ,fahr5heit4 ,^! mat]ials are among ! mo/ difficult to melt t are kn[n4 ,lime is s infusible t x is frequ5tly employ$ = ! mat]ials ( crucibles 9 :i* ! highe/ melt+ metals are fus$1 & = ! p5cils 9 ! calcium light because x w /& extremely high temp]atures4 ,c>bon is ! mat]ial employ$ 9 ! manufacture ( arc light electrodes & o!r electrical appliances t mu/ /& extreme heat4 ,yet ^! two sub/ances are =c$ into comb9ation 9 ! manufacture ( calcium c>bide4 ,x is ! excessively high temp]ature atta9able 9 ! electric furnace t causes ?is comb9ation & n any effect ( ! electricity o!r ?an ! heat produc$4 ,a mixture ( gr\nd coke & lime is introduc$ into ! furnace ?r\gh :i* an electric arc has be5 drawn4 ,! mat]ials unite & =m an +ot ( v pure c>bide surr\nd$ by a cru/ ( less purity4 ,! poor] cru/ is reject$ 9 break+ up ! mass into lumps :i* are grad$ accord+ to _! size4 ,! l>ge/ size is #b by #c-a_/b in*es & is call$ lump1 a m$ium size is #a_/b by #b in*es & is call$ egg1 an int]m$iate size = c]ta9 types ( g5]ators is #c_/h by #a-a_/d in*es & call$ nut1 & ! f9ely cru%$ pieces = use 9 /ill o!r types ( g5]ators are #a_/ab by #a_/d in* 9 size & are call$ qu>t]4 ,in/ructions z to ! size be/ suit$ to diff]5t g5]ators are furni%$ by ! mak]s ( ^? in/rum5ts4 ,^! sizes are pack$ 9 air-tight %eet /eel drums conta9+ #ajj p\nds ea*4 ,! ,union ,c>bide ,company ( ,*icago & ,new ,york1 op]at+ "u pat5ts1 manufactures & di/ributes ! supply ( calcium c>bide = ! entire ,unit$ ,/ates4 ,plants = ?is manufacture are e/abli%$ at ,niag>a ,falls1 ,new ,york1 & ,sault ,/e4 ,m>ie1 ,mi*igan4 ,?is company ma9ta9s a sy/em ( w>eh\ses 9 m ?an "o hundr$ & t5 cities1 :]e l>ge /ocks ( all sizes are c>ri$4 ,! ,national ,bo>d ( ,fire ,und]writ]s gives ! foll[+ rules = ! /orage ( c>bide3 ,calcium c>bide 9 quantities n to exce$ six hundr$ p\nds may be /or$1 :5 conta9$ 9 approv$ metal packages n to exce$ "o hundr$ p\nds ea*1 inside insur$ prop]ty1 provid$ t ! place ( /orage be dry1 wat]pro( & well v5tilat$ & also provid$ t all b "o ( ! packages 9 any "o build+ %all be seal$ & t seals %all n be brok5 s long z !re is c>bide 9 excess ( "o p\nd 9 any o!r unseal$ package 9 ! build+4 ,calcium c>bide 9 quantities 9 excess ( six hundr$ p\nds mu/ be /or$ above gr\nd 9 deta*$ build+s1 us$ exclusively = ! /orage ( calcium c>bide1 9 approv$ metal packages1 & su* build+s %all be con/ruct$ to be dry1 wat]pro( & well v5tilat$4 ,prop]ties ( ,acetyl5e4--,?is gas is compos$ ( tw5ty-f\r p>ts ( c>bon & two p>ts ( hydrog5 by weight & is class$ ) natural gas1 petroleum1 etc41 z "o ( ! hydroc>bons4 ,?is gas conta9s ! highe/ p]c5tage ( c>bon kn[n to exi/ 9 any comb9ation ( ?is =m & x may !re=e be consid]$ z gase\s c>bon4 ,c>bon is ! fuel t is us$ 9 all =ms ( combu/ion & is pres5t 9 all fuels f :atev] s\rce or 9 :atev] =m4 ,acetyl5e is !re=e ! mo/ p[]ful ( all fuel gases & is able to give to ! tor* flame 9 weld+ ! highe/ temp]ature ( any flame4 ,acetyl5e is a colorless & ta/eless gas1 possess$ ( a peculi> & p5etrat+ odor4 ,! lea/ trace 9 ! air ( a room is easily notic$1 & if ?is odor is detect$ ab\t an app>atus 9 op]ation1 x is c]ta9 to indicate a leakage ( gas ?r\gh faulty pip+1 op5 valves1 brok5 hose or o!rwise4 ,?is leakage mu/ be prev5t$ be=e proce$+ ) ! "w to be done4 ,all gases :i* burn 9 air w1 :5 mix$ ) air previ\s to ignition1 produce m or less viol5t explosions1 if fir$4 ,to ?is rule acetyl5e is no exception4 ,"o measure ( acetyl5e & twelve & "o-half ( air are requir$ = complete combu/ion2 ?is is !re=e ! proportion = ! mo/ p]fect explosion4 ,?is is n ! only possible mixture t w explode1 = all proportions f ?ree to ?irty p] c5t ( acetyl5e 9 air w explode ) m or less =ce if ignit$4 ,! ignit+ po9t ( acetyl5e is l[] ?an t ( coal gas1 be+ ab\t #ijj degrees ,fahr5heit z aga9/ elev5 hundr$ degrees = coal gas4 ,! gas issu+ f a tor* w ignite if all[$ to play on ! tip ( a light$ cig>4 ,x is /ill fur!r true t acetyl5e1 at "s pressures1 great] ?an normal1 has "u mo/ favorable conditions = ! effect1 be5 f\nd to explode2 yet x may be /at$ ) p]fect confid5ce t "u no circum/ances has anyone ev] secur$ an explosion 9 x :5 subject$ to pressures n exce$+ fifte5 p\nds to ! squ>e in*4 ,al?\gh n explod$ by ! application ( high heat1 acetyl5e is injur$ by su* treatm5t4 ,x is p>tly conv]t$1 by high heat1 into o!r comp\nds1 ?us less5+ ! actual quantity ( ! gas1 wa/+ x & pollut+ ! re/ by ! introduction ( sub/ances :i* d n belong !re4 ,^! comp\nds rema9 9 "p ) ! gas1 caus+ x to burn ) a p]si/5t smoky flame & ) ! deposit ( objectionable t>ry sub/ances4 ,:]e ! gas is g5]at$ )\t undue rise ( temp]ature ^! difficulties are avoid$4 ,purification ( ,acetyl5e4--,impurities 9 ?is gas are caus$ by impurities 9 ! calcium c>bide f :i* x is made or by improp] me?ods & lack ( c>e 9 g5]ation4 ,impurities f ! mat]ial w be consid]$ fir/4 ,impurities 9 ! c>bide may be fur!r divid$ into two classes3 ^? :i* ex]t no action on wat] & ^? :i* act ) ! wat] to ?r[ (f o!r gase\s products :i* rema9 9 ! acetyl5e4 ,^? impurities :i* ex]t no action on ! wat] consi/ ( coke t has n be5 *ang$ 9 ! furnace & s& & "s o!r sub/ances :i* are h>mless except t !y increase ! a% left aft] ! acetyl5e has be5 g5]at$4 ,an analysis ( ! gas com+ f a typical g5]ator is z foll[s3 ,p] c5t ,acetyl5e 44444444444444444444444444444444 #ii4cf ,oxyg5 44444444444444444444444444444444444 4#jh ,nitrog5 444444444444444444444444444444444 4#aa ,hydrog5 444444444444444444444444444444444 4#jf ,sulphurett$ ,hydrog5 44444444444444444444 4#ag ,phosphorett$ ,hydrog5 4444444444444444444 4#jd ,ammonia 4444444444444444444444444444444444 4#aj ,silicon ,hydride 44444444444444444444444444 4#jc ,c>bon ,monoxide 44444444444444444444444444 4#ja ,me?ane 4444444444444444444444444444444444 4#jd ,! oxyg51 nitrog51 hydrog51 me?ane & c>bon monoxide are ei!r h>mless or are pres5t 9 su* small quantities z to be neglect$4 ,! phosphorett$ hydrog5 & silicon hydride are self-inflammable gases :5 expos$ to ! air1 b _! quantity is s v small t ?is possibility may be dismiss$4 ,! ammonia & sulphurett$ hydrog5 are almo/ entirely dissolv$ by ! wat] us$ 9 ! gas g5]ator4 ,! sure/ way to avoid impure gas is to use high-grade calcium c>bide 9 ! g5]ator & ! c>bide ( ,am]ican manufacture is n[ s pure t x nev] causes tr\ble4 ,! fir/ & mo/ important purification to :i* ! gas is subject$ is its passage ?r\gh ! body ( wat] 9 ! g5]ator z x bubbles to ! top4 ,x is !n filt]$ ?r\gh felt to remove ! solid p>ticles ( lime du/ & o!r impurities :i* float 9 ! gas4 ,fur!r purification to remove ! rema9+ ammonia1 sulphurett$ hydrog5 & phosphorus conta9+ comp\nds is accompli%$ by *emical means4 ,if ?is is consid]$ necess>y x c be easily accompli%$ by readily available purify+ app>atus :i* c be atta*$ to any g5]ator or ins]t$ betwe5 ! g5]ator & tor* outlets4 ,! foll[+ mixtures h be5 us$4 ,h]atol1 a solution ( *romic acid or sulphuric acid absorb$ 9 por\s e>?4 ,acag9e1 a mixture ( blea*+ p[d] ) fifte5 p] c5t ( lead *romate4 ,puratyl5e1 a mixture ( blea*+ p[d] & hydroxide ( lime1 made v por\s1 & conta9+ f eighte5 to tw5ty p] c5t ( active *lor9e4 ,frankol9e1 a mixture ( cupr\s & f]ric *lorides dissolv$ 9 /rong hydro*loric acid absorb$ 9 infusorial e>?4 ,a te/ = impure acetyl5e gas is made by plac+ a drop ( t5 p] c5t solution ( silv] nitrate on a :ite blott] & hold+ ! pap] 9 a /ream ( gas com+ f ! tor* tip4 ,black5+ ( ! pap] 9 a %ort l5g? ( "t indicates impurities4 ,acetyl5e 9 ,tanks4--,acetyl5e is soluble 9 wat] to a v limit$ ext5t1 too limit$ to be ( practical use4 ,!re is only "o liquid t possesses suffici5t p[] ( conta9+ acetyl5e 9 solution to be ( comm]cial value1 ?is be+ ! liquid acetone4 ,acetone is produc$ 9 v>i\s ways1 (t5times f ! di/illation ( wood4 ,x is a transp>5t1 colorless liquid t fl[s ) ease4 ,x boils at #acc ,fahr5heit1 is inflammable & burns ) a lum9\s flame4 ,x has a peculi> b r agreeable odor4 ,acetone dissolves tw5ty-f\r times its own bulk ( acetyl5e at ord9>y atmosph]ic pressure4 ,if ?is pressure is increas$ to two atmosph]es1 #ad4g p\nds above ord9>y pressure1 x w dissolve j twice z mu* ( ! gas & = ea* atmosph]e t ! pressure is increas$ x w dissolve z mu* m4 ,if acetyl5e be compress$ above fifte5 p\nds p] squ>e in* at ord9>y temp]ature )\t fir/ be+ dissolv$ 9 acetone a dang] is pres5t ( self-ignition4 ,?is dang]1 :ile practically no?+ at fifte5 p\nds1 increases ) ! pressure until at =ty atmosph]es x is v explosive4 ,mix$ ) acetone1 ! gas loses ?is dang]\s prop]ty & is safe = h&l+ & transportation4 ,z acetyl5e is dissolv$ 9 ! liquid ! acetone increases its volume slightly s t :5 ! gas has be5 drawn out ( a clos$ tank a space is left full ( free acetyl5e4 ,?is la/ difficulty is remov$ by fir/ fill+ ! cyl9d] or tank ) "s por\s mat]ial1 su* z asbe/os1 wood *>coal1 infusorial e>?1 etc4 ,asbe/os is us$ 9 practice & by a sy/em ( pack+ & support+ ! absorb5t mat]ial no space is left = ! free gas1 ev5 :5 ! acetyl5e has be5 completely )drawn4 ,! acetyl5e is g5]at$ 9 ! usual way & is wa%$1 purifi$ & dri$4 ,great c>e is us$ to make ! gas z free z possible f all impurities & f air4 ,! gas is =c$ into conta9]s fill$ ) acetone z describ$ & is compress$ to "o hundr$ & fifty p\nds to ! squ>e in*4 ,f ^! tanks x is transf]r$ to ! small] portable cyl9d]s = consum]s' use4 ,! exact volume ( gas rema9+ 9 a cyl9d] at atmosph]ic temp]ature may be calculat$ if ! weight ( ! cyl9d] empty is kn[n4 ,"o p\nd ( ! gas occupies #ac4f cubic feet1 s t if ! diff]5ce 9 weight betwe5 ! empty cyl9d] & ! "o consid]$ be multipli$ by #ac4f4 ! result w be ! numb] ( cubic feet ( gas conta9$4 ,! cyl9d]s conta9 f #ajj to #ejj cubic feet ( acetyl5e "u pressure4 ,!y _c be fill$ ) ! ord9>y type ( g5]ator z !y require special purify+ & compress+ app>atus1 :i* %\ld nev] be in/all$ 9 any build+ :]e o!r "w is be+ c>ri$ on1 or ne> o!r build+s :i* are occupi$1 because ( ! dang] ( explosion4 ,dissolv$ acetyl5e is manufactur$ by ! ,pre/-,o-,lite ,company1 ! ,comm]cial ,acetyl5e ,company & ! ,se>*light ,gas ,company & is di/ribut$ f w>eh\ses 9 v>i\s cities4 ,^! tanks %\ld n be dis*>g$ at a rate p] h\r great] ?an "o-sev5? ( _! total capacity1 t is1 f a tank ( #ajj cubic feet capacity1 ! dis*>ge %\ld n be m ?an f\rte5 cubic feet p] h\r4 ,if dis*>ge is c>ri$ on at an excessive rate ! acetone is drawn out ) ! gas & r$uces ! heat ( ! weld+ flame4 ,= ?is reason weld+ %\ld n be attempt$ ) cyl9d]s design$ = automobile & boat light+4 ,:5 ! "w dem&s a great] deliv]y ?an "o ( ! l>g] tanks w give1 two or m tanks may be connect$ ) a special c\pl] su* z may be secur$ f ! mak]s & di/ribut]s ( ! gas4 ,^! c\pl]s may be arrang$ = two1 ?ree1 f\r or five tanks 9 "o batt]y by remov+ ! plugs on ! body ( ! c\pl] & atta*+ additional connect+ pipes4 ,! c\pl] body c>ries a pressure gauge & ! valve = controll+ ! pressure ( ! gas z x fl[s to ! weld+ tor*es4 ,! foll[+ capacities %\ld be provid$ =3 ,acetyl5e ,consumption ,comb9$ ,capacity ( ( ,tor*es p] ,h\r ,cyl9d]s 9 ,use ,up to #ae feet44444444444444444444444#ajj cubic feet #af to #cj feet44444444444444444444444#bjj cubic feet #ca to #de feet44444444444444444444444#cjj cubic feet #df to #fj feet44444444444444444444444#djj cubic feet #fa to #ge feet44444444444444444444444#ejj cubic feet ,,weld+ ,,rods ,! be/ weld+ _c be done )\t us+ ! be/ grade ( mat]ials1 & ! add$ co/ ( ^! mat]ials ov] less desirable =ms is s slight :5 comp>$ to ! quality ( "w p]=m$ & ! wa/e ( gases ) inf]ior supplies1 t x is v unpr(itable to take any *ances 9 ?is respect4 ,! mak]s ( weld+ equipm5t c>ry an assortm5t ( supplies t h be5 /&>diz$ & t may be reli$ ^u to produce ! desir$ result :5 prop]ly us$4 ,! safe/ plan is to secure ?is class ( mat]ial f ! mak]s4 ,weld+ rods1 or weld+ /icks1 are us$ to supply ! additional metal requir$ 9 ! body ( ! weld to replace t brok5 or cut away & also to add to ! jo9t :5ev] possible s t ! "w may h ! same or great] /r5g? ?an t f\nd 9 ! orig9al piece4 ,a rod ( ! same mat]ial z t be+ weld$ is us$ :5 bo? p>ts ( ! "w are ! same4 ,:5 dissimil> metals are to be jo9$ rods ( a composition suit$ to ! "w are employ$4 ,^! fill+ rods are requir$ 9 all "w except /eel ( less ?an #af gauge4 ,alloy iron rods are us$ = ca/ iron4 ,^! rods h a high silicon cont5t1 ! silicon react+ ) ! c>bon 9 ! iron to produce a s(t] & m easily ma*9$ weld ?an w\ld o!rwise be ! case4 ,^! rods are (t5 made s t !y melt at a slightly l[] po9t ?an ca/ iron4 ,?is is done = ! reason t :5 ! "p be+ weld$ has be5 br\ght to ! fus+ heat by ! tor*1 ! fill+ mat]ial c be in/antly melt$ 9 )\t all[+ ! p>ts to cool4 ,! metal c be add$ fa/] & m easily controll$4 ,rods or wires ( ,norway iron are us$ = /eel weld+ 9 almo/ all cases4 ,! purity ( ?is grade ( iron gives a homog5e\s1 s(t weld ( ev5 texture1 great ductility & exceptionally good ma*9+ qualities4 ,= weld+ heavy /eel ca/+s1 a rod ( roll$ c>bon /eel is employ$4 ,= work+ on high c>bon /eel1 a rod ( ! /eel be+ weld$ mu/ be employ$ & = alloy /eels1 su* z nickel1 manganese1 vanadium1 etc41 special rods ( suitable alloy composition are pref]able4 ,alum9um weld+ rods are made f ?is metal alloy$ to give ! ev5 fl[+ t is ess5tial4 ,alum9um is "o ( ! mo/ difficult ( all ! metals to h&le 9 ?is "w & ! selection ( ! prop] rod is ( great importance4 ,brass is fill$ ) brass wire :5 9 small ca/+s & %eets4 ,= g5]al "w ) brass ca/+s1 manganese bronze or ,tob9 bronze may be us$4 ,bronze is weld$ ) manganese bronze or ,tob9 bronze1 :ile copp] is fill$ ) copp] wire4 ,^! weld+ rods %\ld always be us$ to fill ! weld :5 ! ?ickness ( mat]ial makes _! employm5t necess>y1 & additional metal %\ld always be add$ at ! weld :5 possible z ! jo9t _c h ! same /r5g? z ! orig9al piece if made or dress$ (f flu% ) ! surfaces ar\nd ! weld4 ,?is is true because ! metal weld$ into ! jo9t is a ca/+ & w nev] h m /r5g? ?an a ca/+ ( ! mat]ial us$ = fill+4 ,great c>e %\ld be ex]cis$ :5 add+ metal f weld+ rods to make sure t no metal is add$ at a po9t t is n itself melt$ & molt5 :5 ! addition is made4 ,:5 molt5 metal is plac$ ^u cool] surfaces ! result is n a weld b m]ely a /ick+ toge!r ( ! two p>ts )\t any /r5g? 9 ! jo9t4 ,,fluxes ,difficulty w\ld be exp]i5c$ 9 weld+ ) only ! metal & rod to "w ) because ( ! scale t =ms on _m mat]ials "u heat1 ! oxides ( o!r metals & ! impurities f\nd 9 almo/ all metals4 ,^! ?+s t5d to prev5t a p]fect jo9+ ( ! metals & "s means are necess>y to prev5t _! action4 ,v>i\s *emicals1 usually 9 p[d] =m1 are us$ to accompli% ! result ( clean+ ! weld & mak+ ! "w ( ! op]ator less difficult4 ,!y are call$ fluxes4 ,a flux is us$ to float (f physical impurities f ! molt5 metal2 to furni% a protect+ coat+ ar\nd ! weld2 to assi/ 9 ! removal ( any objectionable oxide ( ! metals be+ h&l$2 to l[] ! temp]ature at :i* ! mat]ials fl[2 to make a clean] weld & to produce a bett] quality ( metal 9 ! f9i%$ "w4 ,! flux mu/ be ( su* composition t x w accompli% ! desir$ result )\t introduc+ new difficulties4 ,!y may be prep>$ by ! op]ator 9 _m cases or may be secur$ f ! mak]s ( weld+ app>atus1 ! same rem>ks apply+ to _! quality z 7 made reg>d+ ! weld+ rods1 t is1 only ! be/ %\ld be consid]$4 ,! flux us$ = ca/ iron %\ld h a s(t5+ effect & %\ld prev5t burn+ ( ! metal4 ,9 _m cases x is possible & ev5 pref]able to weld ca/ iron )\t ! use ( a flux1 & 9 any ev5t ! small] ! quantity us$ ! bett] ! result %\ld be4 ,flux %\ld n be add$ j be=e ! completion ( ! "w because ! heat w n h "t to drive ! add$ elem5ts out ( ! metal or to incorporate !m ) ! metal prop]ly4 ,alum9um %\ld nev] be weld$ )\t us+ a flux because ( ! oxide =m$4 ,?is oxide1 call$ alum9a1 does n melt until a heat ( #e1jjj ,fahr5heit is rea*$1 f\r times ! heat ne$$ to melt ! alum9um itself4 ,x is necess>y t ?is oxide be brok5 d[n or dissolv$ s t ! alum9um may h a *ance to fl[ toge!r4 ,copp] is ano!r metal t requires a flux because ( its rapid oxidation "u heat4 ,:ile ! flux is (t5 ?r[n or spr9kl$ along ! break :ile weld+1 mu* bett] results w be obta9$ by dipp+ ! hot end ( ! weld+ rod into ! flux :5ev] ! "w ne$s x4 ,suffici5t p[d] w /ick on ! end ( ! rod = all purposes1 & ) "s fluxes too mu* w adh]e4 ,c>e %\ld always be us$ to avoid ! application ( excessive flux1 z ?is is usually worse ?an us+ too little4 ,,supplies ,,& ,,fixtures ,goggles4--,! oxy-acetyl5e tor* %\ld n be us$ )\t ! protection to ! eyes af=d$ by goggles4 ,^! n only relieve unnecess>y /ra91 b make x mu* easi] to wat* ! exact progress ( ! "w ) ! molt5 metal4 ,! difficulty ( protect+ ! sight :ile weld+ is ev5 great] ?an :5 cutt+ metal ) ! tor*4 ,acetyl5e gives a light :i* is ne>e/ to sunlight ( any artificial illum9ant4 ,b = ! fact t ?is gas light gives a little m gre5 & less blue 9 its composition1 x w\ld be ! same 9 quality & practically ! same 9 int5sity4 ,?is light f ! gas is almo/ abs5t dur+ weld+1 be+ lo/ ) ! addition ( ! extra oxyg5 ne$$ to produce ! weld+ heat4 ,! light t is dang]\s comes f ! molt5 metal :i* fl[s "u ! tor* at a bright :ite heat4 ,goggles = protection aga9/ ?is light & ! heat t goes ) x may be secur$ 9 v>i\s t9ts1 ! d>k] glass be+ = weld+ & ! light] = cutt+4 ,^? hav+ frames 9 :i* ! metal p>ts d n t\* ! fle% directly are mo/ desirable because ( ! high temp]ature rea*$ by ^! p>ts4 ,gloves4--,:ile n z necess>y z are ! goggles1 gloves are a conv5i5ce 9 _m cases4 ,^? 9 :i* lea!r t\*es ! h&s directly are really ( little value z ! heat t protection is desir$ aga9/ makes ! lea!r s hot t no?+ is ga9$ 9 com=t4 ,gloves are made ) asbe/os clo?1 :i* are n op5 to ?is objection 9 s great a degree4 ,illu/ration3 ,figure #i4--;,frame = ,weld+ ,/& ,tables & ,/&s4--,tables = hold+ "w :ile be+ weld$ 7,figure #i7 are usually made f l5g?s ( angle /eel weld$ toge!r4 ,! top %\ld be rectangul>1 ab\t two feet wide & two & "o-half feet long4 ,! legs %\ld support ! work+ surface at a height ( ?irty-two to ?irty-six in*es f ! floor4 ,metal lattice "w may be fa/5$ or laid 9 ! top framework & us$ to support a lay] ( firebrick b\nd toge!r ) a mixture ( "o-?ird cem5t & two-?irds fireclay4 ,! piece be+ weld$ is brac$ & support$ on ?is table ) pieces ( firebrick s t x w rema9 /ation>y dur+ ! op]ation4 ,hold]s = support+ ! tanks ( gas may be made or pur*as$ 9 =ms t re/ directly on ! floor or t are m\nt$ on :eels4 ,^! hold]s are q useful :]e ! floor or gr\nd is v unev54 ,hose4--,all p]man5t l9es f tanks & g5]ators to ! tor*es are made ) pip+ rigidly support$1 b ! %ort di/ance f ! end ( ! pipe l9e to ! tor* itself is complet$ ) a flexible hose s t ! op]ator may be free 9 8 movem5ts :ile weld+4 ,an accid5t ?r\gh :i* ! gases mix 9 ! hose & are ignit$ w bur/ ?is "p ( ! equipm5t1 ) m or less pa9ful results to ! p]son h&l+ x4 ,= t reason x is well to use hose ) great en\gh /r5g? to )/& excessive pressure4 ,a poor grade ( hose w also break d[n inside & clog ! fl[ ( gas1 bo? ?r\gh itself & ?r\gh ! p>ts ( ! tor*4 ,to avoid outside damage & cuts ?is hose is sometimes encas$ ) coil$ %eet metal4 ,hose may be secur$ ) a bur/+ /r5g? ( m ?an #a1jjj p\nds to ! squ>e in*4 ,_m op]ators pref] to di/+ui% betwe5 ! oxyg5 & acetyl5e l9es by _! color & to all[ ?is1 r$ is us$ = ! oxyg5 & black = acetyl5e4 ,o!r ,mat]ials4--,%eet asbe/os & asbe/os fibre 9 flakes are us$ to cov] p>ts ( ! "w :ile prep>+ !m = weld+ & dur+ ! op]ation itself4 ,! flakes & small pieces t become deta*$ f ! l>ge %eets are ?r[n into a b9 :]e ! complet$ small "w is plac$ to all[ sl[ & ev5 cool+ :ile protect$ by ! asbe/os4 ,asbe/os fibre & also ord9>y fireclay are (t5 us$ to make a back+ or m\ld into a =m t may be plac$ beh9d alum9um & "s o!r metals t fl[ at a l[ heat & :i* are accord+ly difficult to h&le "u ord9>y me?ods4 ,?is =ms a solid m\ld into :i* ! metal is practically ca/ z melt$ by ! tor* s t ! desir$ %ape is secur$ )\t dang] ( ! walls ( metal break+ ?r\gh & fl[+ away4 ,c>bon blocks & rods are made 9 v>i\s %apes & sizes s t !y may be us$ to fill ?read$ holes & o!r places t x is desir$ to protect dur+ weld+4 ,^! may be secur$ 9 rods ( v>i\s diamet]s up to "o in* & 9 blocks ( sev]al diff]5t dim5sions4 ,,*apt] ,,iii ,,acetyl5e ,,g5]ators ,acetyl5e g5]ators us$ = produc+ ! gas f ! action ( wat] on calcium c>bide are divid$ into ?ree pr9cipal classes accord+ to ! pressure "u :i* !y op]ate4 ,l[ pressure g5]ators are design$ to op]ate at "o p\nd or less p] squ>e in*4 ,m$ium pressure sy/ems deliv] ! gas at n to exce$ fifte5 p\nds to ! squ>e in* :ile high pressure types furni% gas above fifte5 p\nds p] squ>e in*4 ,high pressure sy/ems are almo/ unkn[n 9 ?is c\ntry1 ! m$ium pressure type be+ (t5 ref]r$ to z high pressure4 ,ano!r important di/9ction is =m$ by ! me?od ( br++ ! c>bide & wat] toge!r4 ,! majority ( ^? n[ 9 use op]ate by dropp+ small quantities ( c>bide into a l>ge volume ( wat]1 all[+ ! g5]at$ gas to bubble up ?r\gh ! wat] be=e be+ collect$ above ! surface4 ,?is type is kn[n z ! c>bide to wat] g5]ator4 ,a less us$ type br+s a measur$ & small quantity ( wat] to a comp>atively l>ge body ( ! c>bide1 ! gas be+ =m$ & collect$ f ! *amb] 9 :i* ! action takes place4 ,?is is call$ ! wat] to c>bide type4 ,ano!r way ( express+ ! diff]5ce 9 fe$ is t ( designat+ ! two types z c>bide fe$ = ! =m] & wat] fe$ = ! latt]4 ,a fur!r division ( ! c>bide to wat] ma*9es is made by m5tion+ ! exact me?od ( fe$+ ! c>bide4 ,"o type1 call$ gravity fe$ op]ates by all[+ ! c>bide to escape & fall by ! action ( its own weight1 or gravity2 ! o!r type1 call$ =c$ fe$1 includes a sep>ate me*anism driv5 by p[]4 ,?is me*anism fe$s def9ite am\nts ( ! c>bide to ! wat] z requir$ by ! dem&s on ! g5]ator4 ,! action ( ei!r fe$ is controll$ by ! )drawal ( gas f ! g5]ator1 ! aim be+ to supply suffici5t c>bide to ma9ta9 a ne>ly con/ant supply4 ,g5]ator ,requirem5ts4--,! qualities ( a good g5]ator are outl9$ z foll[s3 ,footnote3 ,see ,pond's ,calcium ,c>bide & ,acetyl5e4 ,x mu/ all[ no possibility ( ! exi/5ce ( an explosive mixture 9 any ( its p>ts at any "t4 ,x is n en\gh to argue t a mixture1 ev5 if x exi/s1 _c be explod$ unless k9dl$4 ,x is necess>y to dem& t a dang]\s mixture c at no "t be =m$1 ev5 if ! ma*9e is tamp]$ ) by an ignorant p]son4 ,! p]fect ma*9e mu/ be s con/ruct$ t x %all be impossible at any "t1 "u any circum/ances1 to bl[ x up4 ,x mu/ insure cool g5]ation4 ,s9ce ?is is a relative t]m1 all ma*9es be+ heat$ some:at dur+ ! g5]ation ( gas1 ?is am\nts to say+ t a ma*9e mu/ heat b little4 ,a p\nd ( c>bide decompos$ by wat] develops ! same am\nt ( heat "u all circum/ances1 b t heat c be all[$ to increase locally to a high po9t1 or x c be equaliz$ by wat] s t no "p ( ! mat]ial becomes heat$ en\gh to d damage4 ,x mu/ be well con/ruct$4 ,a good g5]ator does n ne$1 p]haps1 to be built l a wat*1 b x %\ld be solid1 sub/antial & ( good mat]ial4 ,x %\ld be built = s]vice1 to la/ & n simply to sell2 any?+ %ort ( ?is is to be avoid$ z unsafe & unreliable4 ,x mu/ be simple4 ,! m complicat$ ! ma*9e ! soon] x w get out ( ord]4 ,und]/& y\r g5]ator4 ,"k :at is inside ( x & bew>e ( an app>atus1 h[ev] attractive its ext]ior1 ^: int]ior is fill$ ) pipes & tubes1 valves & diaphragms ^: functions y d n p]fectly und]/&4 ,x %\ld be capable ( be+ clean$ & re*>g$ & ( receiv+ all o!r necess>y att5tion )\t loss ( gas1 bo? = economy's sake1 & m p>ticul>ly to avoid dang] ( fire4 ,x %\ld require little att5tion4 ,all ma*9es h to be empti$ & re*>g$ p]iodically2 b ! m ?is process is simplifi$ & ! m quickly ?is c be accompli%$1 ! bett]4 ,x %\ld be provid$ ) a suitable indicator to designate h[ l[ ! *>ge is 9 ord] t ! refill+ may be done 9 good season4 ,x %\ld completely use up ! c>bide1 g5]at+ ! maximum am\nt ( gas4 ,ov]heat+4--,a l>ge am\nt ( heat is lib]at$ :5 acetyl5e gas is =m$ f ! union ( calcium c>bide & wat]4 ,ov]heat+ dur+ ?is process1 t is to say1 an int5se local heat r ?an a l>ge am\nt ( heat well di/ribut$1 br+s ab\t ! ph5om5on ( polym]ization1 conv]t+ ! gas1 or "p ( x1 into oily matt]s1 :i* c d no?+ b h>m4 ,?is t>ry mass com+ ?r\gh ! small op5+s 9 ! tor*es causes !m to become p>tly clos$ & alt]s ! proportions ( ! gases to ! detrim5t ( ! weld+ flame4 ,! only rem$y = ?is tr\ble is to avoid its cause & secure cool g5]ation4 ,ov]heat+ c be detect$ by ! appe>ance ( ! sludge rema9+ aft] ! gas has be5 made4 ,discoloration1 yell[ or br[n1 %[s t !re has be5 tr\ble 9 ?is direction & ! resultant effects at ! tor*es may be look$ =4 ,! abundance ( wat] 9 ! c>bide to wat] ma*9es effects ?is cool+ naturally & is a *>act]i/ic ( well design$ ma*9es ( ?is class4 ,x has be5 f\nd be/ & has practically become a fundam5tal rule ( g5]ation t a gallon ( wat] mu/ be provid$ = ea* p\nd ( c>bide plac$ 9 ! g5]ator4 ,) ?is ratio & a g5]ator l>ge en\gh = ! numb] ( tor*es to be suppli$1 little tr\ble ne$ be look$ = ) ov]heat+4 ,wat] to ,c>bide ,g5]ators4--,x is1 ( c\rse1 mu* easi] to obta9 a measur$ & regul> fl[ ( wat] ?an to obta9 su* a fl[ ( any solid sub/ance1 especially :5 ! solid sub/ance is 9 ! =m ( lumps1 z is c>bide ,?is fact l$ to ! use ( a great _m wat]-fe$ g5]ators = all classes ( "w1 & ?is type is /ill 9 common use = ! small portable ma*9es1 su*1 = in/ance1 z ^? us$ on motor c>s = ! lamps4 ,! wat]-fe$ ma*9e is n1 h[ev]1 favor$ = weld+ plants1 z is ! c>bide fe$1 9 spite ( ! great] difficulties att5d+ ! h&l+ ( ! solid mat]ial4 ,a wat]-fe$ g5]ator is made up ( ! gas produc+ "p & a hold] = ! acetyl5e aft] x is made4 ,! c>bide is held 9 a tray =m$ ( a numb] ( small comp>tm5ts s t ! *>ge 9 ea* comp>tm5t is ne>ly equal to t 9 ea* ( ! o!rs4 ,! wat] is all[$ to fl[ into "o ( ^! comp>tm5ts 9 a volume suffici5t to produce ! desir$ am\nt ( gas & ! c>bide is completely us$ f ?is "o division4 ,! wat] !n floods ! fir/ comp>tm5t & f9ally ov]fl[s into ! next "o1 :]e ! same process is repeat$4 ,aft] us+ ! c>bide 9 ?is division1 x is flood$ 9 turn & ! wat] pass+ on to ^? next 9 ord]1 uses ! entire *>ge ( ! :ole tray4 ,^! g5]ators are *>g$ ) ! l>g] sizes ( c>bide & are easily tak5 c>e (4 ,! residue is remov$ 9 ! tray & empti$1 mak+ ! g5]ator ready = a fre% supply ( c>bide4 ,c>bide to ,wat] ,g5]ators4--,?is type also is made up ( two pr9cipal p>ts1 ! g5]at+ *amb] & a gas hold]1 ! hold] be+ "p ( ! g5]at+ *amb] or a sep>ate device4 ,! g5]ator 7,figure #aj7 conta9s a hopp] to receive ! *>ge ( c>bide & is fitt$ ) ! fe$+ me*anism to drop ! prop] am\nt ( c>bide into ! wat] z requir$ by ! dem&s ( ! tor*es4 ,! *>ge ( c>bide is ( "o ( ! small] sizes1 usually nut or qu>t]4 ,fe$ ,me*anisms4--,! device = dropp+ ! c>bide into ! wat] is ! only "p ( ! ma*9e t is at all complicat$4 ,?is complication is br\ght ab\t by ! necessity ( controll+ ! mass ( c>bide s t x c nev] be dis*>g$ into ! wat] at an excessive rate1 fe$+ x at a regul> rate & 9 def9ite am\nts1 fe$+ x positively :5ev] requir$ & %utt+ (f ! fe$ j z positively :5 ! supply ( gas 9 ! hold] is en\gh = ! imm$iate ne$s4 ,illu/ration3 ,figure #aj4--;,c>bide to ,wat] ,g5]ator4 ,a4 ,fe$ motor weight2 ,b4 ,c>bide fe$ motor2 ,c4 ,c>bide hopp]2 ,d4 ,wat] = gas g5]ation2 ,e4 ,agitator = loos5+ residuum2 ,f4 ,wat] seal 9 gas bell2 ,g4 ,filt]2 ,h4 ,hydraulic ,valve2 ,j4 ,motor control lev]s4 ,! *>ge ( c>bide is unavoidably act$ ^u by ! wat] vapor 9 ! g5]ator & w 9 "t become m or less pa/y & /icky4 ,?is is m noticeable if ! g5]ator /&s idle = a consid]able l5g? ( "t ,?is condition imposes ano!r duty on ! fe$+ me*anism2 t is1 ! necessity ( self-clean+ s t ! c>bide1 no matt] 9 :at condition1 _c prev5t ! positive action ( ?is "p ( ! device1 especially s t x _c prev5t ! supply f be+ /opp$ at ! prop] "t4 ,! gas hold] is usually made 9 ! bell =m s t ! upp] portion rises & falls ) ! addition to or )drawal f ! supply ( gas 9 ! hold]4 ,! rise & fall ( ?is bell is (t5 us$ to control ! fe$ me*anism because ?is movem5t indicates positively :e!r en\gh gas has be5 made or t m is requir$4 ,z ! bell l[]s x sets ! fe$ me*anism 9 motion1 & :5 ! gas pass+ into ! hold] has rais$ ! bell a suffici5t di/ance1 ! movem5t causes ! fe$ me*anism to /op ! fall ( c>bide into ! wat]4 ,9 practice1 ! movem5t ( ?is "p ( ! hold] is held )9 v n>r[ limits4 ,gas ,hold]s4--,no matt] h[ close ! adju/m5t ( ! fe$+ device1 !re w always be a slight am\nt ( gas made aft] ! fall ( c>bide is /opp$1 ?is be+ caus$ by ! evolution ( gas f ! c>bide ) :i* wat] is already 9 contact4 ,?is action is call$ aft] g5]ation & ! gas hold] 9 any type ( g5]ator mu/ provide suffici5t capacity to accommodate ?is excess gas4 ,z a g5]al rule ! wat] to c>bide g5]ator requires a l>g] gas hold] ?an ! c>bide to wat] type because ( ! great] am\nt ( c>bide be+ act$ ^u by ! wat] at any "o "t1 also because ! surface ( c>bide pres5t$ to ! moi/ air )9 ! g5]at+ *amb] is great] ) ?is type4 ,freez+4--,because ( ! r l>ge body ( wat] conta9$ 9 any type ( g5]ator1 !re is always dang] ( its freez+ & r5d]+ ! device inop]ative unless plac$ 9 a temp]ature above ! freez+ po9t ( ! wat]4 ,x is1 ( c\rse1 dang]\s & aga9/ ! insurance rules to place a g5]ator 9 ! same room ) a fire ( any k9d1 b ! room may be heat$ by /eam or hot wat] coils f a furnace 9 ano!r build+ or 9 ano!r "p ( ! same build+4 ,:5 ! g5]ator is h\s$ 9 a sep>ate /ructure ! walls %\ld be made ( mat]ials or con/ruction t prev5ts ! passage ( heat or cold ?r\gh !m to any great ext5t4 ,?is may be accompli%$ by ! use ( holl[ tile or concrete blocks or by any o!r =m ( d\ble wall provid+ air spaces betwe5 ! out] & inn] fac+s4 ,! space betwe5 ! p>ts ( ! wall may be fill$ ) mat]ials t fur!r ret>d ! loss ( heat if ?is is necess>y "u ! conditions prevail+4 ,residue ,f ,g5]ators4--,! sludge rema9+ 9 ! c>bide to wat] g5]ator may be drawn (f into ! sew] if ! pip+ is run at a slant great en\gh to give a fall t c>ries ! :ole quantity1 bo? wat] & a%1 away )\t all[+ settl+ & consequ5t clogg+4 ,g5]ators are provid$ ) agitators :i* are op]at$ to /ir ! a% up ) ! wat] s t ! :ole mass is c>ri$ (f :5 ! dra9 cock is op5$4 ,if sew] connections _c be made 9 su* a way t ! a% is entirely c>ri$ away1 x is be/ to run ! liquid mass into a settl+ bas9 outside ( ! build+4 ,?is %\ld be 9 ! =m ( a %all[ pit :i* w all[ ! wat] to pass (f by soak+ into ! gr\nd & by evaporation1 leav+ ! comp>atively dry a% 9 ! pit4 ,?is a% :i* rema9s is ess5tially slak$ lime & c (t5 be dispos$ ( to m or less advantage to be us$ 9 mort>1 :itewa%1 m>k+ pa?s & any o!r use = :i* slak$ lime is suit$4 ,! disposition ( ! a% dep5ds entirely on local conditions4 ,an av]age analysis ( ?is a% is z foll[s3 ,s&44444444444444444444444 #a4aj p] c5t4 ,c>bon444444444444444444444 #b4gb ,oxide ( iron & alum9a44 #b4gg ,lime44444444444444444444444 #fd4jf ,wat] & c>bonic acid4444 #bi4ce ------ #ajj4jj ,,g5]ator ,,con/ruction ,! wat] = g5]at+ purposes is c>ri$ 9 ! l>ge tank-l comp>tm5t directly bel[ ! c>bide *amb]4 ,see ,figure #aa4 ,?is wat] comp>tm5t is fill$ ?r\gh a pipe ( su* a height t ! wat] level _c be br\ght above ! prop] po9t or else ! wat] comp>tm5t is provid$ ) a dra9 connection :i* accompli%es ?is same result by all[+ an excess to fl[ away4 ,! quantity ( wat] dep5ds on ! capacity ( ! g5]ator inasmu* z !re mu/ be "o gallon = ea* p\nd ( c>bide requir$4 ,! g5]ator %\ld be ( suffici5t capacity to furni% gas "u work+ conditions f "o *>ge ( c>bide to all tor*es in/all$ = at lea/ five h\rs cont9u\s use4 ,aft] calculat+ ! )drawal ( ! :ole numb] ( tor*es accord+ to ! "w !y are to d = ?is p]iod ( five h\rs ! prop] g5]ator capacity may be f\nd on ! basis ( "o cubic foot ( gas p] h\r = ea* p\nd ( c>bide4 ,?us if ! tor*es 7 to use sixty cubic feet ( gas p] h\r1 five h\rs w\ld call = ?ree hundr$ cubic feet & a ?ree hundr$ p\nd g5]ator %\ld be in/all$4 ,g5]ators are rat$ accord+ to _! c>bide capacity 9 p\nds4 ,*>g+4--,! c>bide capacity ( ! g5]ator %\ld be great en\gh to furni% a cont9u\s supply ( gas = ! maximum op]at+ "t1 bas+ ! quantity ( gas g5]at$ on f\r & "o-half cubic feet f ea* p\nd ( lump c>bide & on f\r cubic feet f ea* p\nd ( qu>t]1 int]m$iate sizes be+ 9 proportion4 ,g5]ators are built 9 su* a way t x is impossible = ! acetyl5e to escape f ! gas hold+ comp>tm5t dur+ ! re*>g+ process4 ,?is is accompli%$ 7#a7 by connect+ ! wat] inlet pipe op5+ ) a %ut (f valve 9 su* a way t ! inlet _c be uncov]$ or op5$ )\t fir/ clos+ ! %ut (f valve ) ! same movem5t ( ! op]ator2 7#b7 by incorporat+ an automatic or hydraulic "o-way valve s t ?is valve closes & acts z a *eck :5 ! gas attempts to fl[ f ! hold] back to ! g5]at+ *amb]1 or by any o!r means t w positively accompli% ?is result4 ,9 g5]ators hav+ no sep>ate gas hold+ *amb] b c>ry+ ! supply 9 ! same comp>tm5t 9 :i* x is g5]at$1 ! gas conta9$ "u pressure is all[$ to escape ?r\gh v5t pipes into ! outside air be=e re*>g+ ) c>bide4 ,z 9 ! =m] case1 ! p>ts are s int]lock$ t x is impossible to introduce c>bide or wat] )\t fir/ all[+ ! escape ( ! gas 9 ! g5]ator4 ,x is requir$ by ! insurance rules t ! entire *ange ( c>bide :ile 9 ! g5]ator be held 9 su* a way t x may be entirely remov$ )\t difficulty 9 case ! necessity %\ld arise4 ,g5]ators %\ld be clean$ & re*>g$ at regul> /at$ int]vals4 ,?is "w %\ld be done dur+ daylight h\rs only & likewise all repairs %\ld be made at su* a "t t artificial light is n ne$$4 ,:]e x is absolutely necess>y to use artificial light x %\ld be provid$ only by inc&esc5t electric lamps enclos$ 9 gas tight globes4 ,9 *>g+ g5]at+ *amb]s ! old a% & all residue mu/ fir/ be clean$ out & ! op]ator %\ld be sure t no dra9 or o!r pipe has become clogg$4 ,! g5]ator %\ld !n be fill$ ) ! requir$ am\nt ( wat]4 ,9 *>g+ c>bide fe$ ma*9es be c>eful n to place less ?an a gallon ( wat] 9 ! wat] comp>tm5t = ea* p\nd ( c>bide to be us$ & ! wat] mu/ be br\ght to1 b n above1 ! prop] level z indicat$ by ! m>k or ! mak]'s in/ructions4 ,! g5]at+ *amb] mu/ be fill$ ) ! prop] am\nt ( wat] be=e any attempt is made to place ! c>bide 9 its hold]4 ,?is rule mu/ always be foll[$4 ,x is also necess>y t all automatic wat] seals & valves1 z well z any o!r wat] tanks1 be fill$ ) clean wat] at ?is "t4 ,nev] re*>ge ) c>bide )\t fir/ clean+ ! g5]at+ *amb] & completely refill+ ) clean wat]4 ,nev] te/ ! g5]ator or pip+ = leaks ) any flame1 & nev] apply flame to any op5 pipe or at any po9t o!r ?an ! tor*1 & only to ! tor* aft] x has a weld+ or cutt+ nozzle atta*$4 ,nev] use a light$ mat*1 lamp1 c&le1 lant]n1 cig> or any op5 flame ne> a g5]ator4 ,failure to obs]ve ^! precautions is liable to endang] life & prop]ty4 ,op]ation & ,c>e ( ,g5]ators4--,! foll[+ in/ructions apply especially to ! ,davis ,b\rnonville pressure g5]ator1 illu/rat$ 9 ,figure #aa4 ,! motor fe$ me*anism is illu/rat$ 9 ,figure #ab4 ,be=e fill+ ! ma*9e1 ! cov] %\ld be remov$ & ! hopp] tak5 out & exam9$ to see t ! fe$+ disc revolves freely2 t no *a9s h be5 displac$ or brok51 & t ! c>bide displac] itself hangs b>ely free ( ! fe$+ disc :5 x is revolv$4 ,aft] replac+ ! cov]1 replace ! bolts & tight5 !m equally1 a little at a "t all ar\nd ! circumf]5ce ( ! cov]--n screw+ tight 9 "o place only4 ,d n screw ! cov] d[n any m ?an is necess>y to make a tight fit4 ,to *>ge ! g5]ator1 proce$ z foll[s3 ,op5 ! v5t valve by turn+ ! h&le :i* ext5ds ov] ! fill+ tube until x /&s at a "r angle ) ! g5]ator4 ,op5 ! valve 9 ! wat] fill+ pipe1 & ?r\gh ?is fill ) wat] until x runs out ( ! ov]fl[ pipe ( ! dra9age *amb]1 !n close ! valve 9 ! wat] fill+ pipe & v5t valve4 ,remove ! c>bide fill+ plugs & fill ! hopp] ) #a-a_/dx#c_/h c>bide 7nut size74 ,!n replace ! plugs & ! safety-lock+ lev] *a9s4 ,n[ rew9d ! motor weight4 ,run ! pressure up to ab\t five p\nds by rais+ ! controll+ diaphragm valve lev] by h& 7,figure #ab1 lev] m>k$ ,e74 ,!n raise ! bl[-(f lev]1 all[+ ! gas to bl[ (f until ! gauge %[s ab\t two p\nds2 ?is to cle> ! g5]ator ( air mixture4 ,!n run ! pressure up to ab\t eight p\nds by rais+ ! controll+ valve lev] ,e1 or until ?is controll+ lev] re/s aga9/ ! upp] w+ ( ! fan gov]nor1 & prev5ts op]ation ( ! fe$ motor4 ,aft] ?is is done1 ! motor w op]ate automatically z ! gas is consum$4 ,illu/ration3 ,figure #aa4--,pressure ,g5]ator 7,davis ,b\rnonville74 ,a1 ,fe$ motor weight2 ,b1 ,c>bide fe$ motor2 ,c1 ,motor ,control diaphragm2 ,d1 ,c>bide hopp]2 ,e1 ,c>bide fe$ disc2 ,f1 ,ov]fl[ pipe2 ,g1 ,ov]fl[ pipe seal2 ,h1 ,ov]fl[ pipe valve2 ,j1 ,fill+ funnel2 ,k1 ,hydraulic valve2 ,l1 ,expansion *amb]2 ,m1 ,escape pipe2 ,n1 ,fe$ pipe2 ,o1 ,agitator = residuum2 ,p1 ,residuum valve2 ,q1 ,wat] level ,illu/ration3 ,figure #ab4--;,fe$ ,me*anism ( ,pressure ,g5]ator ,%\ld ! pressure rise mu* above ! bl[-(f po9t1 ! safety controll+ diaphragm valve w op]ate & ?r[ ! safety clut* 9 int]f]5ce & ?us /op ! motor4 ,?is int]f]5ce clut* w !n h to be return$ to its =m] position be=e ! motor w op]ate1 b _c be replac$ be=e ! pressure has be5 r$uc$ bel[ ! bl[-(f po9t4 ,! p>ts ( ! fe$ me*anism illu/rat$ 9 ,figure #ab are z foll[s3 ,a1 motor drum = weight cable4 ,b1 c>bide fill+ plugs4 ,c1 *a9s = connect+ safety lock+ lev] ( motor to p9s on ! top ( ! c>bide plugs4 ,d1 int]f]5ce clut* ( motor4 ,e1 lev] on fe$ controll+ diaphragm valve4 ,f1 lev] ( int]f]5ce controll+ diaphragm valve t op]ates int]f]5ce clut*4 ,g1 fe$ controll+ diaphragm valve4 ,h1 diaphragm valve controll+ op]ation ( int]f]5ce clut*4 ,i1 int]f]5ce p9 to engage em]g5cy clut*4 ,j1 ma9 %aft driv+ c>bide fe$+ disc4 ,y1 safety lock+ lev]4 ,re*>g+ ,g5]ator4--,turn ! agitator h&le rapidly = sev]al revolutions1 & !n op5 ! residuum valve1 hav+ five or six p\nds gas pressure on ! ma*9e4 ,if ! c>bide *>ge has be5 exhau/$ & ! motor has /opp$1 !re is g5]ally en\gh c>bide rema9+ 9 ! fe$+ disc t c be %ak5 (f1 & f$ by runn+ ! motor to obta9 "s pressure 9 ! g5]ator4 ,! desirability ( dis*>g+ ! residuum ) "s gas pressure is because ! pressure facilitates ! dis*>ge & at ! same "t keeps ! g5]ator full ( gas1 prev5t+ air mixture to a great ext5t4 ,z soon z ! pressure is reliev$ by ! )drawal ( ! residuum1 ! v5t valve %\ld be op5$1 z if ! pressure is ma9ta9$ until all ( ! residuum is dis*>g$ gas w\ld escape ?r\gh ! dis*>ge valve4 ,hav+ op5$ ! v5t pipe valve & reliev$ ! pressure1 op5 ! valve 9 ! wat] fill+ tube4 ,close ! residuum valve1 !n run 9 sev]al gallons ( wat] & revolve ! agitator1 aft] :i* draw out ! rema9+ residuum2 !n aga9 close ! residuum valve & p\r 9 wat] until x dis*>ges f ! ov]fl[ pipe ( ! dra9age *amb]4 ,x is desirable 9 fill+ ! g5]ator to p\r ! wat] 9 rapidly en\gh to keep ! fill+ pipe full ( wat]1 s t air w n pass 9 at ! same "t4 ,aft] ! g5]ator is clean$ & fill$ ) wat]1 fill ) c>bide & proce$ 9 ! same mann] z :5 fir/ *>g+4 ,c>bide ,fe$ ,me*anism4--,any =m ( c>bide to wat] ma*9e %\ld be s design$ t ! c>bide nev] falls directly f its hold] into ! wat]1 b s t x mu/ take a m or less circuit\s pa?4 ,?is %\ld be true1 no matt] :at position ! me*anism is 94 ,"o ( ! commone/ types ( =c$ fe$ ma*9e c>ries ! c>bide 9 a hopp] ) slant+ sides1 ?is hopp] hav+ a l>ge op5+ 9 ! bottom ?r\gh :i* ! c>bide passes to a revolv+ circul> plate4 ,z ! pieces ( c>bide "w out t[>d ! edge ( ! plate "u ! influ5ce ( ! mass beh9d !m1 !y are ?r[n (f into ! wat] by small /ation>y f9s or pl[s :i* are 9 su* a position t !y cat* ! pieces ne>e/ ! edges & =ce !m (f z ! plate revolves4 ,?is arrangem5t1 :ile all[+ a free passage = ! c>bide1 prev5ts an excess f fall+ %\ld ! ma*9e /op 9 any position4 ,:51 z is usually ! case1 ! fe$ me*anism is actuat$ by ! rise or fall ( pressure 9 ! g5]ator or ( ! level ( "s "p ( ! gas hold]1 x mu/ be built 9 su* a way t ! fe$+ rema9s inop]ative z long z ! fill+ op5+ on ! c>bide hold] rema9s op54 ,! fe$ ( c>bide %\ld always be %ut (f & controll$ s t "u no condition c m gas be g5]at$ ?an c\ld be c>$ = by ! relief valve provid$4 ,x is necess>y also to h ! fe$ me*anism at lea/ t5 in*es above ! surface ( ! wat] s t ! p>ts w nev] become clogg$ ) damp lime du/4 ,motor ,fe$4--,! fe$ me*anism itself is usually op]at$ by p[] secur$ f a sl[ly fall+ weight :i*1 ?r\gh a cable1 revolves a drum4 ,to ?is drum is atta*$ suitable ge>+ = mov+ ! fe$ p>ts ) suffici5t p[] & 9 ! way desir$4 ,?is "p1 call$ ! motor1 is controll$ by two lev]s1 "o releas+ a brake & all[+ ! motor to op]ate ! fe$1 ! o!r lock+ ! ge>+ s t no m c>bide w be dropp$ into ! wat]4 ,^! lev]s are mov$ ei!r by ! quantity ( gas 9 ! hold] or by ! pressure ( ! gas1 dep5d+ on ! type ( ma*9e4 ,) a sep>ate gas hold]1 su* z us$ ) l[ pressure sy/ems1 ! lev]s are op]at$ by ! rise & fall ( ! bell ( ! hold] or gasomet]1 alt]nately />t+ & /opp+ ! motor z ! bell falls & rises aga94 ,m$ium pressure g5]ators are provid$ ) a diaphragm to control ! fe$ motor4 ,?is diaphragm is c>ri$ s t ! pressure )9 ! g5]ator acts on "o side :ile a spr+1 ^: t5sion is "u ! control ( ! op]ator1 acts on ! o!r side4 ,! diaphragm is connect$ to ! brake & lock+ device on ! motor 9 su* a way t increas+ ! t5sion on ! spr+ presses ! diaphragm & moves a rod t releases ! brake & />ts ! fe$4 ,! gas pressure1 increas+ ) ! cont9uation ( c>bide fe$1 acts on ! o!r side & f9ally ov]comes ! pressure ( ! spr+ t5sion1 mov+ ! control rod ! o!r way & /opp+ ! motor & c>bide fe$4 ,?is spr+ t5sion is adju/$ & *eck$ ) ! help ( a pressure gauge atta*$ to ! g5]at+ *amb]4 ,gravity ,fe$4--,?is type ( fe$ diff]s f ! =ego+ 9 t ! c>bide is simply releas$ & is all[$ to fall into ! wat] )\t be+ =c$ to d s4 ,any =m ( valve t is suffici5tly p[]ful 9 action to close ) ! c>bide pass+ ?r\gh is us$ & is op]at$ by ! p[] secur$ f ! rise & fall ( ! gas hold] bell4 ,:5 ?is valve is fir/ op5$ ! c>bide runs into ! wat] until suffici5t pressure & volume ( gas is g5]at$ to raise ! bell4 ,?is movem5t op]ates ! arm atta*$ to ! c>bide %ut (f valve & sl[ly closes x4 ,a fall ( ! bell occasion$ by gas be+ )drawn aga9 op5s ! valve & m gas is g5]at$4 ,me*anical ,fe$4--,! previ\sly describ$ me?ods ( fe$+ c>bide to ! wat] h all be5 automatic 9 action & d n dep5d on ! op]ator = _! prop] action4 ,"s types ( l>ge g5]at+ plants h a p[]-driv5 fe$1 ! p[] usually be+ f "s k9d ( motor o!r ?an "o op]at$ by a weight1 su* z a wat] motor1 = in/ance4 ,?is motor is />t$ & /opp$ by ! op]ator :51 9 8 judgm5t1 m gas is want$ or en\gh has be5 g5]at$4 ,?is type ( ma*9e1 (t5 call$ a non-automatic g5]ator1 is suitable = l>ge in/allations & is atta*$ to a gas hold] ( suffici5t size to hold a day's supply ( acetyl5e4 ,! g5]ator c !n be op]at$ until a quantity ( gas has be5 made t w fill ! l>ge hold]1 or gasomet]1 & !n all[$ to rema9 idle = "s "t4 ,gas ,hold]s4--,! commone/ type ( gas conta9] is t kn[n z a gasomet]4 ,?is consi/s ( a circul> tank p>tly fill$ ) wat]1 into :i* is l[]$ ano!r circul> tank1 inv]t$1 :i* is made en\gh small] 9 diamet] ?an ! fir/ "o s t ?ree-qu>t]s ( an in* is left betwe5 !m4 ,?is upp] & inv]t$ portion1 call$ ! bell1 receives ! gas f ! g5]ator & rises or falls 9 ! ba? ( wat] provid$ 9 ! l[] tank z a great] or less am\nt ( gas is conta9$ 9 x4 ,^! hold]s are made l>ge en\gh s t !y w provide a means ( c>+ = any aft] g5]ation & s t !y ma9ta9 a /eady & ev5 fl[4 ,! g5]ator1 h[ev]1 mu/ be ( a capacity great en\gh s t ! gas hold] w n be drawn on = "p ( ! supply ) all tor*es 9 op]ation4 ,t is1 ! hold] mu/ n be dep5d$ on = a res]ve supply4 ,! bell ( ! hold] is made s t :5 full ( gas its l[] edge is /ill "u a dep? ( at lea/ n9e in*es ( wat] 9 ! l[] tank4 ,any fur!r rise beyond ?is po9t %\ld always release ! gas1 or at lea/ "p ( x1 to ! escape pipe s t ! gas w "u no circum/ances be =c$ into ! room f1 betwe5 ! bell & tank4 ,! bell is guid$ 9 its rise & fall by v]tical rods s t x w n w$ge at any po9t 9 its travel4 ,a cond5s+ *amb] to receive ! wat] :i* cond5ses f ! acetyl5e gas 9 ! hold] is usually plac$ "u ?is "p & is provid$ ) a dra9 s t ?is wat] ( cond5sation may be easily remov$4 ,filt]+4--,a small *amb] conta9+ "s closely pack$ b por\s mat]ial su* z felt is plac$ 9 ! pipe lead+ to ! tor* l9es4 ,z ! acetyl5e gas passes ?r\gh ?is filt] ! p>ticles ( lime du/ & o!r impurities are extract$ f x s t dang] ( clogg+ ! tor* op5+s is avoid$ z mu* z possible4 ,! gas is also filt]$ to a l>ge ext5t by its passage ?r\gh ! wat] 9 ! g5]at+ *amb]1 ?is filt]+ or scrubb+ (t5 be+ facilitat$ by ! =m ( pip+ ?r\gh :i* ! gas mu/ pass f ! g5]at+ *amb] into ! hold]4 ,if ! gas passes out ( a numb] ( small op5+s :5 go+ into ! hold] ! small bubbles give a bett] wa%+ ?an l>ge ones w\ld4 ,pip+4--,connections f g5]ators to s]vice pipes %\ld pref]ably be made ) "r & left c\pl+s or long ?read nipples ) lock nuts4 ,if unions are us$1 !y %\ld be ( a type t does n require gaskets4 ,! pip+ %\ld be c>ri$ & support$ s t any moi/ure cond5s+ 9 ! l9es w dra9 back t[>d ! g5]ator & :]e l[ po9ts occur !y %\ld be dra9$ ?r\gh tees lead+ into drip cups :i* are p]man5tly clos$ ) screw caps or plugs4 ,no pet cocks %\ld be us$ = ?is purpose4 ,= ! fe$ pipes to ! tor* l9es ! foll[+ pipe sizes are recomm5d$4 #c_/h in* pipe4 #bf feet long4 #b cubic feet p] h\r4 #a_/b in* pipe4 #cj feet long4 #d cubic feet p] h\r4 #c_/d in* pipe4 #ej feet long4 #ae cubic feet p] h\r4 #a in* pipe4 #gj feet long4 #bg cubic feet p] h\r4 #a-a_/d in* pipe4 #ajj feet long4 #ej cubic feet p] h\r4 #a-a_/b in* pipe4 #aej feet long4 #fe cubic feet p] h\r4 #b in* pipe4 #bjj feet long4 #abe cubic feet p] h\r4 #b-a_/b in* pipe4 #cjj feet long4 #aij cubic feet p] h\r4 #c in* pipe4 #dej feet long4 #cce cubic feet p] h\r4 ,:5 dra9age is possible into a sew]1 ! g5]ator %\ld n be connect$ directly into ! sew] b %\ld fir/ dis*>ge into an op5 receptacle1 :i* may 9 turn be connect$ to ! sew]4 ,no valves or pet cocks %\ld op5 into ! g5]ator room or any o!r room :5 x w\ld be possible1 by op5+ !m = dra9+ purposes1 to all[ any escape ( gas4 ,any cond5sation mu/ be remov$ )\t ! use ( valves or o!r work+ p>ts1 be+ dra9$ into clos$ receptacles4 ,x %\ld be ne$less to say t all ! pip+ = gas mu/ be p]fectly tight at e po9t 9 its l5g?4 ,safety ,devices4--,good g5]ators are built 9 su* a way t ! op]ator mu/ foll[ ! prop] ord] ( op]ation 9 *>g+ & clean+ z well z 9 all o!r necess>y c>e4 ,x has be5 m5tion$ t ! gas pressure is releas$ or %ut (f be=e x is possible to fill ! wat] comp>tm5t1 & ?is same idea is c>ri$ fur!r 9 mak+ ! g5]ator inop]ative & free f gas pressure be=e op5+ ! residue dra9 ( ! c>bide fill+ op5+ on top ( ! hopp]4 ,"s ma*9es are made s t !y automatically cease to g5]ate %\ld !re be a sudd5 & abnormal )drawal ( gas su* z w\ld be caus$ by a bad leak4 ,?is me?od ( add+ safety by automatic means & int]lock+ p>ts may be c>ri$ to any ext5t t seems desirable or necess>y to ! mak]4 ,all g5]ators %\ld be provid$ ) escape or relief pipes ( l>ge size :i* lead to ! op5 air4 ,^! pipes are c>ri$ s t cond5sation w dra9 back t[>d ! g5]ator & aft] be+ l$ out ( ! build+ to a po9t at lea/ twelve feet above gr\nd1 !y end 9 a protect+ hood s t no ra9 or solid matt] c f9d its way into !m4 ,any escape ( gas :i* might ord9>ily pass into ! g5]ator room is l$ into ^! escape pipes1 all p>ts ( ! sy/em be+ connect$ ) ! pipe s t ! gas w f9d ?is way out4 ,safety bl[ (f valves are provid$ s t any excess gas :i* _c be conta9$ by ! gas hold] may be all[$ to escape )\t caus+ an undue rise 9 pressure4 ,?is valve also all[s ! escape ( pressure above t = :i* ! g5]ator 0 design$4 ,gas releas$ 9 ?is way passes into ! escape pipe j describ$4 ,inasmu* z ! pressure ( ! oxyg5 is mu* great] ?an t ( ! acetyl5e :5 us$ 9 ! tor*1 x w be se5 t any?+ t caus$ ! tor* outlet to become clos$ w\ld all[ ! oxyg5 to =ce ! acetyl5e back into ! g5]ator & ! oxyg5 w\ld foll[ x1 mak+ a v explosive mixture4 ,?is return ( ! gas is prev5t$ by a hydraulic safety valve or back pressure valve1 z x is (t5 call$4 ,me*anical *eck valves h be5 f\nd unsuitable = ?is use & ^? :i* employ wat] z a seal are n[ requir$ by ! insurance rules4 ,! valve itself 7,figure #ac7 consi/s ( a l>ge cyl9d] conta9+ wat] to a c]ta9 dep?1 :i* is indicat$ on ! valve body4 ,two pipes come into ! upp] end ( ?is cyl9d] & lead d[n into ! wat]1 "o be+ long] ?an ! o!r4 ,! %ort] pipe leads to ! escape pipe m5tion$ above1 :ile ! long] "o comes f ! g5]ator4 ,! upp] end ( ! cyl9d] has an op5+ to :i* is atta*$ ! pipe lead+ to ! tor*es4 ,illu/ration3 ,figure #ac4--;,hydraulic ,back-,pressure ,valve4 ,a1 ,acetyl5e supply l9e2 ,b1 ,v5t pipe2 ,c1 ,wat] fill+ plug2 ,d1 ,acetyl5e s]vice cock2 ,e1 ,plug to gauge height ( wat]2 ,f1 ,gas op5+s "u wat]2 ,g1 ,return pipe = seal+ wat]2 ,h1 ,tube to c>ry gas bel[ wat] l9e2 ,i1 ,tube to c>ry gas to escape pipe2 ,j1 ,gas *amb]2 ,k1 ,plug 9 upp] gas *amb]2 ,l1 ,high wat] level2 ,m1 ,op5+ ?r\gh :i* wat] returns2 ,o1 ,bottom clean out ca/+ ,! gas com+ f ! g5]ator ?r\gh ! long] pipe passes out ( ! l[] end ( ! pipe :i* is "u wat] & bubbles up ?r\gh ! wat] to ! space 9 ! top ( ! cyl9d]4 ,f !re ! gas goes to ! pipe lead+ to ! tor*es4 ,! %ort] pipe is clos$ by ! dep? ( wat] s t ! gas does n escape to ! relief pipe4 ,z long z ! gas fl[s 9 ! normal direction z describ$ !re w be no escape to ! air4 ,%\ld ! gas 9 ! tor* l9e return into ! hydraulic valve its pressure w l[] ! level ( wat] 9 ! cyl9d] by =c+ "s ( ! liquid up into ! two pipes4 ,z ! level ( ! wat] l[]s1 ! %ort] pipe w be uncov]$ fir/1 & z ?is is ! pipe lead+ to ! op5 air ! gas w be all[$ to escape1 :ile ! pipe lead+ back to ! g5]ator is /ill clos$ by ! wat] seal4 ,z soon z ?is rev]se fl[ ceases1 ! wat] w aga9 resume its level & ! action w cont9ue4 ,because ( ! small am\nt ( wat] bl[n out ( ! escape pipe ea* "t ! valve is call$ ^u to p]=m ?is duty1 x is necess>y to see t ! correct wat] level is always ma9ta9$4 ,:ile !re are modifications ( ?is con/ruction1 ! same pr9ciple is us$ 9 all types4 ,! pressure escape valve is (t5 atta*$ to ?is hydraulic valve body4 ,con/ruction ,details4--,flexible tub+ 7except at tor*es71 sw+ pipe jo9ts1 spr+s1 me*anical *eck valves1 *a9s1 pulleys & lead or fusible pip+ %\ld nev] be us$ on acetyl5e app>atus except :]e ! failure ( ^? p>ts w n affect ! safety ( ! ma*9e or p]mit1 ei!r directly or indirectly1 ! escape ( gas into a room4 ,floats %\ld n be us$ except :]e failure w only r5d] ! ma*9e inop]ative4 ,x %\ld be said t ! ,national ,bo>d ( ,fire ,und]writ]s h e/abli%$ an inspection s]vice = acetyl5e g5]ators & any app>atus :i* be>s _! label1 /at+ t t p>ticul> model & type has be5 pass$1 is safe to use4 ,?is s]vice is = ! be/ int]e/s ( all conc]n$ & looks t[>d ! prev5tion ( accid5ts4 ,su* inspection is a v important & desirable feature ( any outfit & %\ld be insi/$ ^u4 ,location ( ,g5]ators4--,g5]ators %\ld pref]ably be plac$ outside ( insur$ build+s & 9 prop]ly con/ruct$ g5]ator h\ses4 ,! op]at+ me*anism %\ld h ample room to "w 9 & !re %\ld be room en\gh = ! att5dant to rea* ! v>i\s p>ts & p]=m ! requir$ duties )\t h9drance or ! ne$ ( artificial light4 ,!y %\ld also be protect$ f tamp]+ by unau?oriz$ p]sons4 ,g5]ator h\ses %\ld n be )9 five feet ( any op5+ into1 nor h any op5+ t[>d1 any adjac5t build+1 & %\ld be kept "u lock & key4 ,! size ( ! h\se %\ld be no great] ?an call$ = by ! requirem5ts m5tion$ above & x %\ld be well v5tilat$4 ,! f\ndation = ! g5]ator itself %\ld be ( brick1 /one1 concrete or iron1 if possible4 ,if ( wood1 !y %\ld be extra heavy1 locat$ 9 a dry place & op5 to circulation ( air4 ,a bo>d plat=m is n satisfactory1 b ! f\ndation %\ld be ( heavy plank+ or timb] to make a firm base & s t ! air c circulate ar\nd ! wood4 ,! g5]ator %\ld /& level & no /ra9 %\ld be plac$ on any ( ! pipes or connections or any p>ts ( ! g5]ator prop]4 ,,*apt] ,,iv ,,weld+ ,,in/rum5ts ,,valves ,tank ,valves4--,! acetyl5e tank valve is ( ! ne$le type1 fitt$ ) suitable /uff+ box nuts & end+ 9 an expos$ squ>e %ank to :i* ! special wr5* may be fitt$ :5 ! valve is to be op5$ or clos$4 ,! valve us$ on ,l9de oxyg5 cyl9d]s is also a ne$le type1 b ( slightly m complex con/ruction4 ,! body ( ! valve1 :i* screws into ! top ( ! cyl9d]1 has an op5+ bel[ ?r\gh :i* ! gas comes f ! cyl9d]1 & ano!r op5+ on ! side ?r\gh :i* x issues to ! tor* l9e4 ,a ne$le screws d[n f above to close ?is l[] op5+4 ,! ne$le :i* closes ! valve is n connect$ directly to ! ?read$ memb]1 b fits loosely into x4 ,! ?read$ "p is turn$ by a small h& :eel atta*$ to ! upp] end4 ,:5 ?is h& :eel is turn$ to ! left1 or up1 z f> z x w g1 op5+ ! valve1 a rubb] disc is compress$ inside ( ! valve body & ?is disc s]ves to prev5t leakage ( ! gas ar\nd ! sp9dle4 ,! oxyg5 valve also includes a safety nut hav+ a small hole ?r\gh x clos$ by a fusible metal :i* melts at #bej ,fahr5heit4 ,melt+ ( ?is plug all[s ! gas to ex]t its pressure aga9/ a ?9 copp] diaphragm1 ?is diaphragm bur/+ "u ! gas pressure & all[+ ! oxyg5 to escape into ! air4 ,! h& :eel & upp] end ( ! valve me*anism are protect$ dur+ %ipm5t by a l>ge /eel cap :i* cov]s !m :5 screw$ on to ! end ( ! cyl9d]4 ,?is cap %\ld always be 9 place :5 tanks are receiv$ f ! mak]s or return$ to !m4 ,illu/ration3 ,figure #ad4--,regulat+ ,valve ,regulat+ ,valves4--,:ile ! pressure 9 ! gas conta9]s may be any?+ f z]o to #a1hjj p\nds1 & w v>y z ! gas is )drawn1 ! pressure ( ! gas admitt$ to ! tor* mu/ be held /eady & at a def9ite po9t4 ,?is is accompli%$ by v>i\s =ms ( automatic regulat+ valves1 :i*1 :ile !y diff] some:at 9 details ( con/ruction1 all op]ate on ! same pr9ciple4 ,! regulator body 7,figure #ad7 c>ries a union :i* atta*es to ! side outlet on ! oxyg5 tank valve4 ,! gas passes ?r\gh ?is union1 foll[+ an op5+ :i* leads to a l>ge gauge :i* regi/]s ! pressure on ! oxyg5 rema9+ 9 ! tank & also to a v small op5+ 9 ! end ( a tube4 ,! gas passes ?r\gh ?is op5+ & into ! int]ior ( ! regulator body4 ,inside ( ! body is a metal or rubb] diaphragm plac$ s t ! pressure ( ! incom+ gas causes x to bulge slightly4 ,atta*$ to ! diaphragm is a sleeve or an arm tipp$ ) a small piece ( fibre1 ! fibre be+ plac$ s t x is directly opposite ! small hole ?r\gh :i* ! gas ent]$ ! diaphragm *amb]4 ,! slight movem5t ( ! diaphragm draws ! fibre tightly ov] ! small op5+ ?r\gh :i* ! gas is ent]+1 ) ! result t fur!r fl[ is prev5t$4 ,aga9/ ! opposite side ( ! diaphragm is ! end ( a plung]4 ,?is plung] is press$ aga9/ ! diaphragm by a coil$ spr+4 ,! t5sion on ! coil$ spr+ is controll$ by ! op]ator ?r\gh a ?read$ sp9dle end+ 9 a w+ or mill$ nut on ! outside ( ! regulator body4 ,screw+ 9 on ! nut causes ! t5sion on ! spr+ to increase1 ) a consequ5t increase ( pressure on ! side ( ! diaphragm opposite to t on :i* ! gas acts4 ,inasmu* z ! gas pressure act$ to close ! small gas op5+ & ! spr+ pressure acts 9 ! opposite direction f ! gas1 x w be se5 t ! spr+ pressure t5ds to keep ! valve op54 ,:5 ! nut is turn$ way out !re is ( c\rse1 no pressure on ! spr+ side ( ! diaphragm & ! fir/ gas com+ ?r\gh automatically closes ! op5+ ?r\gh :i* x ent]$4 ,if n[ ! t5sion on ! spr+ be slightly increas$1 ! valve w aga9 op5 & admit gas until ! pressure ( gas )9 ! regulator is j suffici5t to ov]come ! spr+ pressure & aga9 close ! op5+4 ,!re w !n be a pressure ( gas )9 ! regulator t corresponds to ! pressure plac$ on ! spr+ by ! op]ator4 ,an op5+ leads f ! regulator int]ior to ! tor* l9es s t all gas go+ to ! tor*es is drawn f ! diaphragm *amb]4 ,any )drawal ( gas w1 ( c\rse1 l[] ! pressure ( t rema9+ inside ! regulator4 ,! spr+ t5sion1 rema9+ at ! po9t det]m9$ by ! op]ator1 w ov]come ?is less5$ pressure ( ! gas1 & ! valve w aga9 op5 & admit en\gh m gas to br+ ! pressure back to ! />t+ po9t4 ,?is action cont9ues z long z ! spr+ t5sion rema9s at ?is po9t & z long z any gas is tak5 f ! regulator4 ,increas+ ! spr+ t5sion w require a great] gas pressure to close ! valve & ! pressure ( t 9 ! regulator w be correspond+ly high]4 ,:5 ! regulator is n be+ us$1 ! h& nut %\ld be unscrew$ until no t5sion rema9s on ! spr+1 ?us clos+ ! valve4 ,aft] ! oxyg5 tank valve is op51 ! regulator h& nut is sl[ly screw$ 9 until ! spr+ t5sion is suffici5t to give ! requir$ pressure 9 ! tor* l9es4 ,ano!r gauge is atta*$ to ! regulator s t x communicates ) ! int]ior ( ! diaphragm *amb]1 ?is gauge %[+ ! gas pressure go+ to ! tor*4 ,x is cu/om>y to incorporate a safety valve 9 ! regulator :i* w bl[ (f at a dang]\s pressure4 ,9 regulat+ valves & tank valves1 z well z all o!r p>ts ) :i* ! oxyg5 comes 9 contact1 x is n p]missible to use any =m ( oil or grease because ( dang] ( ignition & explosion4 ,! me*anism ( a regulator is too delicate to be h&l$ 9 ! ord9>y %op & %\ld any tr\ble or leakage develop 9 ?is "p ( ! equipm5t x %\ld be s5t to a company famili> ) ?is class ( "w = ! necess>y repairs4 ,gas mu/ nev] be admitt$ to a regulator until ! h& nut is all ! way out1 because ( dang] to ! regulator itself & to ! op]ator z well4 ,a regulator c only be prop]ly adju/$ :5 ! tank valve & tor* valves are fully op5$4 ,illu/ration3 ,figure #ae4--;,high & ,l[ ,pressure ,gauges ) ,regulator ,acetyl5e regulators are us$ 9 connection ) tanks ( compress$ gas4 ,!y are built on exactly ! same l9es z ! oxyg5 regulat+ valve & op]ate 9 a simil> way4 ,"o gauge only1 ! l[ pressure indicator1 is us$ = acetyl5e regulators1 al?\gh bo? high & l[ pressure may be us$ if desir$4 7,see ,figure #ae47 ,,tor*es ,flame is always produc$ by ! combu/ion ( a gas ) oxyg5 & 9 no o!r way4 ,:5 we burn oil or c&les or any?+ else1 ! mat]ial ( ! fuel is fir/ turn$ to a gas by ! heat & is !n burn$ by comb9+ ) ! oxyg5 ( ! air4 ,if m ?an a normal supply ( air is =c$ into ! flame1 a great] heat & m active burn+ foll[s4 ,if ! am\nt ( air1 & consequ5tly oxyg51 is r$uc$1 ! flame becomes small] & weak] & ! combu/ion is less rapid4 ,a flame may be easily ext+ui%$ by %utt+ (f all ( its air supply4 ,! oxyg5 ( ! combu/ion only =ms "o-fif? ( ! total volume ( air2 !re=e1 if we 7 to supply pure oxyg5 9 place ( air1 & 9 equal volume1 ! action w\ld be sev]al times z int5se4 ,if ! oxyg5 is mix$ ) ! fuel gas 9 ! proportion t burns to ! v be/ advantage1 ! flame is /ill fur!r /r5g!n$ & /ill m heat is develop$ because ( ! p]fect combu/ion4 ,! great] ! am\nt ( fuel gas t c be burn$ 9 a c]ta9 space & )9 a c]ta9 "t1 ! m heat w be develop$ f t fuel4 ,! great am\nt ( heat conta9$ 9 acetyl5e gas1 great] ?an t f\nd 9 any o!r gase\s fuel1 is us$ by lead+ ?is gas to ! oxy-acetyl5e tor* & !re comb9+ x ) j ! "r am\nt ( oxyg5 to make a flame ( ! greate/ p[] & heat ?an c possibly be produc$ by any =m ( combu/ion ( fuels ( ?is k9d4 ,! heat develop$ by ! flame is ab\t #fcjj ,fahr5heit & easily melts all ! metals1 z well z o!r solids4 ,o!r gases h be5 & are n[ be+ us$ 9 ! tor*4 ,none ( !m1 h[ev]1 produce ! heat t acetyl5e does1 & !re=e ! oxy-acetyl5e process has prov$ ! mo/ useful ( all4 ,hydrog5 0 us$ = _m ye>s be=e acetyl5e 0 introduc$ 9 ?is field4 ,! oxy-hydrog5 flame develops a heat f> bel[ t ( oxy-acetyl5e1 namely #dejj ,fahr5heit4 ,coal gas1 b5z9e gas1 blaugas & o!rs h also be5 us$ 9 successful applications1 b = ! pres5t we w deal exclusively ) ! acetyl5e fuel4 ,x 0 only ) great difficulty t ! ob/acles 9 ! way ( successfully us+ acetyl5e 7 ov]come by ! developm5t ( practicable controll+ devices & tor*es1 z well z g5]ators4 ,at pres5t ! oxy-acetyl5e process is ! mo/ univ]sally adaptable1 & probably f9ds ! mo/ widely ext5d$ field ( usefulness ( any weld+ process4 ,! !oretical proportion ( ! gases = p]fect combu/ion is two & "o-half volumes ( oxyg5 to "o ( acetyl5e4 ,9 practice ?is proportion is "o & "o-eigh? or "o & "o-qu>t] volumes ( oxyg5 to "o volume ( acetyl5e1 s t ! co/ is consid]ably r$uc$ bel[ :at x w\ld be if ! !oretical quantity 7 really necess>y1 z oxyg5 co/s mu* m ?an acetyl5e 9 all cases4 ,:ile ! heat is s int5se z to fuse any?+ br\ght into ! pa? ( ! flame1 x is localiz$ 9 ! small weld+ cone at ! tor* tip s t ! tor* is n at all difficult to h&le )\t special protection except = ! eyes1 z already not$4 ,! art ( successful weld+ may be acquir$ by any op]ator ( av]age intellig5ce )9 a reasonable "t & ) "s practice4 ,"o tr\ble met ) 9 ! adoption ( ?is process has be5 t ! op]ation looks s simple & s easy ( p]=mance t unskill$ & unprep>$ p]sons h be5 tempt$ to try weld+1 ) results t (t5 caus$ condemnation ( ! process1 :5 ! real fault lay entirely ) ! op]ator4 ,! =m ( tor* usually employ$ is f twelve to tw5ty-f\r in*es long & is compos$ ( a h&le at "o end ) tubes lead+ f ?is h&le to ! weld+ head or tor* prop]4 ,at or ne> "o end ( ! h&le are adju/able cocks or valves = all[+ ! gases to fl[ into ! tor* or to prev5t !m f do+ s4 ,^! cocks are (t5 us$ = regulat+ ! pressure & am\nt ( gas fl[+ to ! weld+ head1 b are n always con/ruct$ = ?is purpose & %\ld n be s us$ :5 x is possible to secure pressure adju/m5t at ! regulators 7,figure #af74 ,figure #af %[s ?ree diff]5t sizes ( tor*es4 ,! numb] #e tor* is design$ especially = jewel]s' "w & ?9 %eet /eel weld+4 ,x is elev5 in*es 9 l5g? & weighs n9ete5 ounces4 ,! tips = ! numb] #aj tor* are int]*angeable ) ! numb] #e4 ,! numb] #aj tor* is adapt$ = g5]al use on light & m$ium heavy "w4 ,x has six tips & its l5g? is sixte5 in*es1 ) a weight ( tw5ty-?ree ounces4 ,! numb] #ae tor* is design$ = heavy "w1 be+ tw5ty-five in*es 9 l5g?1 p]mitt+ ! op]ator to /& away f ! heat ( ! metal be+ work$4 ,^! heavy tips are 9 two p>ts1 ! oxyg5 *eck be+ r5ewable4 ,illu/ration3 ,figure #af4--,?ree ,sizes ( ,tor*es1 ) ,tips ,figures #ag & #ah %[ two sizes ( ano!r weld+ tor*4 ,/ill ano!r type is %[n 9 ,figure #ai ) f\r int]*angeable tips1 ! function ( ea* be+ z foll[s3 ,no4 #a4 ,= heavy ca/+s4 ,no4 #b4 ,light ca/+s & heavy %eet metal4 ,no4 #c4 ,light %eet metal4 ,no4 #d4 ,v light %eet metal & wire4 ,illu/ration3 ,figure #ag4--;,cox ,weld+ ,tor* 7,no4 #a7 ,illu/ration3 ,figure #ah4--;,cox ,weld+ ,tor* 7,no4 #b7 ,illu/ration3 ,figure #ai4--,mon>* ,weld+ ,tor* ,at ! side ( ! %ut (f cock away f ! tor* h&le ! gas tubes end 9 /&>d =ms ( hose nozzles1 to :i* ! rubb] hose f ! gas supply tanks or g5]ators c be atta*$4 ,! tubes f ! h&le to ! head may be entirely sep>ate f ea* o!r1 or "o may be conta9$ )9 ! o!r4 ,z a g5]al rule ! upp] "o ( two sep>ate tubes c>ries ! oxyg51 :ile ?is gas is c>ri$ 9 ! inside tube :5 !y are conc5tric ) ea* o!r4 ,9 ! weld+ head is ! mix+ *amb] design$ to produce an intimate mixture ( ! two gases be=e !y issue f ! nozzle to ! flame4 ,! nozzle1 or weld+ tip1 ( a suitable size are design = ! "w to be h&l$ & ! pressure ( gases be+ us$1 is atta*$ to ! weld+ head & consi/s ess5tially ( ! passage at ! out] end ( :i* ! flame appe>s4 ,! tor* body & tubes are usually made ( brass1 al?\gh copp] is sometimes us$4 ,! jo9t mu/ be v /rong1 & are usually ?read$ & sold]$ ) silv] sold]4 ,! nozzle prop] is made f copp]1 because x )/&s ! heat ( ! flame bett] ?an o!r less suitable metals4 ,! tor* mu/ be built 9 su* a way t x is n at all liable to come ap>t "u ! influ5ce ( high temp]atures4 ,all tor*es are con/ruct$ 9 su* a way t x is impossible = ! gases to mix by any possible *ance be=e !y rea* ! head1 & ! am\nt ( gas conta9$ 9 ! head & tip aft] be+ mix$ is made z small z possible4 ,9 ord] to prev5t ! return ( ! flame ?r\gh ! acetyl5e tube "u ! influ5ce ( ! high pressure oxyg5 "s =m ( back fla% prev5t] is usually incorporat$ 9 ! tor* at or ne> ! po9t at :i* ! acetyl5e ent]s4 ,?is prev5t] takes ! =m ( "s por\s & heat absorb+ mat]ial1 su* z alum9um %av+s1 conta9$ 9 a small cavity ?r\gh :i* ! gas passes on its way to ! head4 ,high ,pressure ,tor*es4--,tor*es are divid$ into ! same classes z are ! g5]ators2 t is1 high pressure1 m$ium pressure & l[ pressure4 ,z m5tion$ be=e1 ! m$ium pressure is usually call$ ! high pressure1 because !re are v few true high pressure sy/ems 9 use1 & comp>atively speak+ ! m$ium pressure type is "o ( high pressure4 ,illu/ration3 ,figure #bj4--;,high ,pressure ,tor* ,head ,) a true high pressure tor* 7,figure #bj7 ! gases are us$ at v ne>ly equal heads s t ! mix+ be=e ignition is a simple matt]4 ,?is type admits ! oxyg5 at ! inn] end ( a /raight passage lead+ to ! tip ( ! nozzle4 ,! acetyl5e comes into ?is same passage f op5+s at "o side & ne> ! inn] end4 ,! diff]5ce 9 direction ( ! two gases z !y ent] ! passage assi/s 9 mak+ a homog5e\s mixture4 ,! con/ruction ( ?is nozzle is p]fectly simple & is easily und]/ood4 ,! true high pressure tor* nozzle is only suit$ = use ) compress$ & dissolv$ acetyl5e1 no o!r gas be+ at a suffici5t pressure to make ! action necess>y 9 mix+ ! gases4 ,m$ium ,pressure ,tor*es4--,! m$ium pressure 7usually call$ high pressure7 tor* 7,figure #ba7 uses acetyl5e f a m$ium pressure g5]ator or f tanks ( compress$ gas1 b w n take ! acetyl5e f l[ pressure g5]ators4 ,illu/ration3 ,figure #ba4--,m$ium ,pressure ,tor* ,head ,! con/ruction ( ! mix+ *amb] & nozzle is v simil> to t ( ! high pressure tor*1 ! gases ent]+ 9 ! same way & f ! same positions ( op5+s4 ,! pressure ( ! acetyl5e is b little l[] ?an t ( ! oxyg51 & ! two gases1 meet+ at "r angles1 =m a v intimate mixture at ?is po9t ( juncture4 ,! mixture 9 its proportions ( gases dep5ds entirely on ! sizes ( ! oxyg5 & acetyl5e op5+s into ! mix+ *amb] & on ! pressures at :i* ! gases are admitt$4 ,!re is a v slight injector action z ! fa/ mov+ /ream ( oxyg5 t5ds to draw ! acetyl5e f ! side op5+s into ! *amb]1 b ! op]ation ( ! tor* does n dep5d on ?is action to any ext5t4 ,l[ ,pressure ,tor*es4--,! l[ pressure tor* 7,figure #bb7 w use gas f l[ pressure g5]ators f m$ium pressure ma*9es or f tanks 9 :i* x has be5 compress$ & dissolv$4 ,?is type dep5ds = a p]fect mixture ( gas ^u ! pr9ciple ( ! injector j z x is appli$ 9 /eam boil] practice4 ,illu/ration3 ,figure #bb4--,l[ ,pressure ,tor* ) ,sep>ate ,injector ,nozzle ,! oxyg5 ent]s ! head at consid]able pressure & passes ?r\gh its tube to a small jet )9 ! head4 ,! op5+ ( ?is jet is directly opposite ! end ( ! op5+ ?r\gh ! nozzle :i* =ms ! mix+ *amb] & ! pa? ( ! gases to ! flame4 ,a small di/ance rema9s betwe5 ! op5+ f :i* ! oxyg5 issues & ! inn] op5+ into ! mix+ passage4 ,! /ream ( oxyg5 ru%es across ?is space & ent]s ! mix+ *amb]1 be+ driv5 by its own pressure4 ,! acetyl5e ent]s ! head 9 an annul> space surr\nd+ ! oxyg5 tube4 ,! space betwe5 oxyg5 jet & mix+ *amb] op5+ is at "o end ( ?is acetyl5e space & ! /ream ( oxyg5 seizes ! acetyl5e & "u ! injector action draws x into ! mix+ *amb]1 x be+ necess>y only to h a suffici5t supply ( acetyl5e fl[+ into ! head to all[ ! oxyg5 to draw ! requir$ proportion = a prop] mixture4 ,! volume ( gas drawn into ! mix+ *amb] dep5ds on ! size ( ! injector op5+s & ! pressure ( ! oxyg54 ,9 practice ! oxyg5 pressure is n alt]$ to produce diff]5t siz$ flames1 b a new nozzle is sub/itut$ :i* is design$ to give ! requir$ flame4 ,ea* nozzle c>ries its own injector1 s t ! design is always suit$ to ! conditions4 ,:ile tor*es are made hav+ ! injector z a p]man5t "p ( ! tor* body1 ! replaceable nozzle is m commonly us$ because x makes ! "o tor* suitable = a l>ge range ( "w & a l>ge numb] ( diff]5t siz$ flames4 ,) ! replaceable head a def9ite pressure ( oxyg5 is requir$ = ! size be+ us$1 ?is pressure be+ ! "o = :i* ! injector & correspond+ mix+ *amb] 7 design$ 9 produc+ ! correct mixture4 ,adju/able ,injectors4-,ano!r =m ( l[ pressure tor* op]ates on ! injector pr9ciple1 b ! injector itself is a p]man5t "p ( ! tor*1 ! nozzle only be+ *ang$ = diff]5t sizes ( "w & flame4 ,! injector is plac$ 9 or ne> ! h&le & its op5+ is ! l>ge/ requir$ by any "w t c be h&l$ by ?is p>ticul> tor*4 ,! op5+ ?r\gh ! tip ( ! injector ?r\gh :i* ! oxyg5 issues on its way to ! mix+ *amb] may be :olly or p>tly clos$ by a ne$le valve :i* may be screw$ into ! op5+ or )drawn f x1 accord+ to ! op]ator's judgm5t4 ,! ne$le valve ends 9 a mill$ nut outside ! tor* h&le1 ?is be+ ! adju/m5t provid$ = ! diff]5t nozzles4 ,tor* ,con/ruction4--,a well design$ tor* is s design$ t ! weight di/ribution is be/ = hold+ x 9 ! prop] position = weld+4 ,:5 a tor* is grasp$ by its h&le ) ! gas hose atta*$1 x %\ld balance s t x does n feel appreciably heavi] on "o end ?an on ! o!r4 ,! head & nozzle may be plac$ s t ! flame issues 9 a l9e at "r angles ) ! tor* body1 or !y may be atta*$ at an angle conv5i5t = ! "w to be done4 ,! head set at an angle ( f #abj to #agj degrees ) ! body is usually pref]r$ = g5]al "w 9 weld+1 :ile ! cutt+ tor* usually has its head at "r angles to ! body4 ,removable nozzles h v>i\s size op5+s ?r\gh !m & ! diff]5t sizes are designat$ by numb]s f #a up4 ,! same numb] does n always indicate ! same size op5+ 9 tor*es ( diff]5t makes1 nor does x indicate a nozzle ( ! same capacity4 ,! design ( ! nozzle1 ! mix+ *amb]1 ! injector1 :5 "o is us$1 & ! size ( ! gas op5+s mu/ be su* t all ^! ?+s are suit$ to ea* o!r if a prop] mixture ( gas is to be secur$4 ,p>ts t are n made to "w toge!r are unsafe if us$ because ( ! dang] ( a fla% back ( ! flame into ! mix+ *amb] & gas tubes4 ,x is well kn[n t flame travels ?r\gh any inflammable gas at a c]ta9 def9ite rate ( spe$1 dep5d+ on ! degree ( inflammability ( ! gas4 ,! easi] & quick] ! gas burns1 ! fa/] w ! flame travel ?r\gh x4 ,if ! gas 9 ! nozzle & mix+ *amb] /ood /ill1 ! flame w\ld imm$iately travel back into ^! p>ts & produce an explosion ( m or less viol5ce4 ,! spe$ ) :i* ! gases issue f ! nozzle prev5t ?is f happ5+ because ! flame travels back ?r\gh ! gas at ! same spe$ at :i* ! gas issues f ! tor* tip4 ,%\ld ! velocity ( ! gas be great] ?an ! spe$ ( flame propagation ?r\gh x1 x w be impossible to keep ! flame at ! tip1 ! t5d5cy be+ = a space ( unburn$ gas to appe> betwe5 tip & flame4 ,on ! o!r h&1 %\ld ! spe$ ( ! flame exce$ ! velocity ) :i* ! gas comes f ! tor* !re w result a fla% back & explosion4 ,c>e ( ,tor*es4--,an oxy-acetyl5e tor* is a v delicate & s5sitive device1 mu* m s t appe>s on ! surface4 ,x mu/ be giv5 equally z good c>e & att5tion z any o!r high-pric$ piece ( ma*9]y if x is to be ma9ta9$ 9 good condition = use4 ,x requires clean+ ( ! nozzles at regul> int]vals if us$ regul>ly4 ,?is clean+ is accompli%$ ) a piece ( copp] or brass wire run ?r\gh ! op5+1 & nev] ) any metal su* z /eel or iron t is h>d] ?an ! nozzle itself1 because ( ! dang] ( *ang+ ! size ( ! op5+s4 ,! tor* head & nozzle c (t5 be clean$ by all[+ ! oxyg5 to bl[ ?r\gh at high pressure )\t ! use ( any tools4 ,9 us+ a tor* a deposit ( c>bon w gradually =m inside ( ! head1 & ?is deposit w be m rapid if ! op]ator lights ! /ream ( acetyl5e be=e turn+ any oxyg5 into ! tor*4 ,?is deposit may be remov$ by runn+ k]os5e ?r\gh ! nozzle :ile x is remov$ f ! tor*1 sett+ fire to ! k]os5e & all[+ oxyg5 to fl[ ?r\gh :ile ! oil is burn+4 ,%\ld a tor* become clogg$ 9 ! head or tubes1 x may usually be clean$ by remov+ ! oxyg5 hose f ! h&le end1 clos+ ! acetyl5e cock on ! tor*1 plac+ ! end ( ! oxyg5 hose ov] ! op5+ 9 ! nozzle & turn+ on ! oxyg5 "u pressure to bl[ ! ob/ruction back ?r\gh ! passage t x has ent]$4 ,by op5+ ! acetyl5e cock & clos+ ! oxyg5 cock at ! h&le1 ! acetyl5e passages may !n be clean$ 9 ! same way4 ,"u no conditions %\ld a tor* be tak5 ap>t any m ?an to remove ! *angeable nozzle1 except 9 ! h&s ( ^? exp]i5c$ 9 ?is "w4 ,nozzle ,sizes4--,! size ( op5+ ?r\gh ! nozzle is det]m9$ accord+ to ! ?ickness & k9d ( metal be+ h&l$4 ,! foll[+ sizes are recomm5d$ = /eel3 ,davis-,b\rnonville4 ,oxweld ,l[ ,?ickness ( ,metal 7,m$ium ,pressure47 ,pressure #a_/cb ,tip ,no4 #a ,head ,no4 #b #a_/af #b #e_/fd #c #c_/cb #c #d #c_/h #d #e #c_/af #e #f #a_/d #f #g #e_/af #g #c_/h #h #h #a_/b #i #aj #e_/h #aj #ab #c_/d #aa #ae ,v heavy #ab #ae ,cutt+ ,tor*es4--,/eel may be cut ) a jet ( oxyg5 at a rate ( spe$ great] ?an 9 any o!r practicable way "u usual conditions4 ,! action consi/s ( burn+ away a ?9 section ( ! metal by all[+ a /ream ( oxyg5 to fl[ onto x :ile ! gas is at high pressure & ! metal at a :ite heat4 ,illu/ration3 ,figure #bc4--;,cutt+ ,tor* ,! cutt+ tor* 7,figure #bc7 has ! same *>act]i/ics z ! weld+ tor*1 b has an additional nozzle or means = tempor>ily us+ ! weld+ op5+ = ! high pressure oxyg54 ,! oxyg5 issues f ! op5+ :ile cutt+ at a pressure ( f t5 to #ajj p\nds to ! squ>e in*4 ,! "w is fir/ heat$ to a :ite heat by adju/+ ! tor* = a weld+ flame4 ,z soon z ! metal rea*es ?is temp]ature1 ! high pressure oxyg5 is turn$ on to ! :ite-hot portion ( ! /eel4 ,:5 ! jet ( gas /rikes ! metal x cuts /raight ?r\gh1 leav+ a v n>r[ slot & remov+ b little metal4 ,?icknesses ( /eel up to t5 in*es c be economically h&l$ 9 ?is way4 ,! oxyg5 nozzle is usually arrang$ s t x is surr\nd$ by a numb] ( small jets = ! heat+ flame4 ,x w be se5 t ?is arrangem5t makes ! heat+ flame always prec$e ! oxyg5 jet1 no matt] 9 :i* direction ! tor* is mov$4 ,! tor* is held firmly1 ei!r by h& or ) ! help ( special me*anism = guid+ x 9 ! desir$ pa?1 & is /eadily advanc$ 9 ! direction x is desir$ to ext5d ! cut1 ! rate ( advance be+ f ?ree in*es to two feet p] m9ute ?r\gh metal f n9e in*es d[n to "o-qu>t] ( an in* 9 ?ickness4 ,! foll[+ data on cutt+ is giv5 by ! ,davis-,b\rnonville ,company3 ,cubic ,feet ,co/ ( ,?ickness ( ,gas ,in*es ,gases ( ,cutt+ ,heat+ p] ,foot ,oxyg5 ,cut p] p] ,foot ,/eel ,oxyg5 ,oxyg5 ( ,cut ,acetyl5e ,m94 ( ,cut #a_/d #aj lbs4 #d lbs4 4#dj 4#jhf #bd 4#jac #a_/b #bj #d 4#ia 4#aej #ae 4#jbi #c_/d #cj #d #a4af 4#aej #ae 4#jcf #a #cj #d #a4de 4#agb #ab 4#jde #a #a_/b #cj #e #b4dj 4#chj #ab 4#jgf #b #dj #e #b4if 4#chj #ab 4#jic #d #ej #e #i4gj 4#hjj #g 4#bii #f #gj #f #ba4ji #a4ej #d 4#fdh #i #ajj #f #dc4bj #b4jj #c #a4caa ,acetyl5e-,air ,tor*4--,a =m ( tor* :i* burns ! acetyl5e aft] mix+ x ) atmosph]ic air at normal pressure r ?an ) ! oxyg5 "u high] pressures has be5 f\nd useful 9 c]ta9 pre-heat+1 braz+ & simil> op]ations4 ,?is tor* 7,figure #bd7 is atta*$ by a rubb] gas hose to any compress$ acetyl5e tank & is regulat$ z to flame size & temp]ature by op5+ or clos+ ! tank valve m or less4 ,aft] atta*+ ! tor* to ! tank1 ! gas is turn$ on v sl[ly & is light$ at ! tor* tip4 ,! adju/m5t %\ld cause ! pres5ce ( a gre5i%-:ite cone ( flame surr\nd$ by a l>g] body ( burn+ gas1 ! cone />t+ at ! m\? ( ! tor*4 ,illu/ration3 ,figure #bd4--;,acetyl5e-,air ,tor* ,by op5+ ! tank valve m1 a long] & hott] flame is produc$1 ! l5g? be+ regulat$ by ! tank valve also4 ,?is tor* w give suffici5t heat to melt /eel1 al?\gh n "u conditions suit$ to weld+4 ,because ( ! excess ( acetyl5e always pres5t !re is no dang] ( oxidiz+ ! metal be+ heat$4 ,! only c>e requir$ by ?is tor* is to keep ! small air passages at ! nozzle clean & free f c>bon deposits4 ,! flame %\ld be ext+ui%$ :5 n 9 use r ?an turn$ l[1 because ?is l[ flame rapidly deposits l>ge quantities ( soot 9 ! burn]4 ,,*apt] ,v ,,oxy-,,acetyl5e ,,weld+ ,,practice ,,prep>ation ,,( ,,"w ,preheat+4--,! practice ( heat+ ! metal ar\nd ! weld be=e apply+ ! tor* flame is a desirable "o = two reasons4 ,fir/1 x makes ! :ole process m economical2 second1 x avoids ! dang] ( breakage ?r\gh expansion & contraction ( ! "w z x is heat$ & z x cools4 ,:5 x is desir$ to jo9 two surfaces by weld+ !m1 x is1 ( c\rse1 necess>y to raise ! metal f ! temp]ature ( ! surr\nd+ air to its melt+ po9t1 involv+ an increase 9 temp]ature ( f "o ?\s& to ne>ly ?ree ?\s& degrees4 ,to obta9 ?is entire increase ( temp]ature ) ! tor* flame is v wa/eful ( fuel & ( ! op]ator's "t4 ,! total am\nt ( heat necess>y to put into metal is increas$ by ! conductivity ( t metal because ! heat appli$ at ! weld is c>ri$ to o!r p>ts ( ! piece be+ h&l$ until ! :ole mass is consid]ably rais$ 9 temp]ature4 ,to secure ?is widely di/ribut$ increase ! v>i\s me?ods ( preheat+ are adopt$4 ,z to ! second reason = prelim9>y heat+4 ,x is und]/ood t ! metal add$ to ! jo9t is molt5 at ! "t x fl[s into place4 ,all ! metals us$ 9 weld+ contract z !y cool & occupy a mu* small] space ?an :5 molt54 ,if additional metal is run betwe5 two adjo9+ surfaces :i* are p>ts ( a surr\nd+ body ( cool metal1 ?is add$ metal w cool :ile ! surfaces !mselves are held /ation>y 9 ! position !y orig9ally occupi$4 ,! inevitable result is t ! metal add$ w crack "u ! /ra91 or1 if ! weld is exceptionally /rong1 ! ma9 body ( ! "w w be brok5 by ! =ce ( contraction4 ,to ov]come ^! difficulties is ! second & mo/ important reason = preheat+ & also = sl[ cool+ foll[+ ! completion ( ! weld4 ,!re are _m ways ( secur+ ?is preheat+4 ,! "w may be br\ght to a r$ heat 9 ! =ge if x is ca/ iron or /eel2 x may be heat$ 9 special ov5s built = ! purpose2 x may be plac$ 9 a b$ ( *>coal :ile suitably support$2 x may be heat$ by gas or gasol9e preheat+ tor*es1 & ) v small "w ! out] flame ( ! weld+ tor* automatically provides means to ?is end4 ,! temp]ature ( ! p>ts heat$ %\ld be gradually rais$ 9 all cases1 giv+ ! entire mass ( metal a *ance to exp& equally & to adju/ itself to ! /ra9s impos$ by ! preheat+4 ,aft] ! region ar\nd ! weld has be5 br\ght to a prop] temp]ature ! op5+ to be fill$ is expos$ s t ! tor* flame c rea* x1 :ile ! rema9+ surfaces are /ill protect$ f cold air curr5ts & f cool+ ?r\gh natural radiation4 ,"o ( ! commone/ me?ods & "o ( ! be/ = h&l+ "w ( r l>ge size is to place ! piece to be weld$ on a b$ ( fire brick & build a loose wall ar\nd x ) o!r fire brick plac$ 9 r[s1 "o on top ( ! o!r1 ) air spaces left betwe5 adjac5t bricks 9 ea* r[4 ,! space betwe5 ! brick reta9+ wall & ! "w is fill$ ) *>coal1 :i* is light$ f bel[4 ,! top op5+ ( ! tempor>y ov5 is !n cov]$ ) asbe/os & ! fire kept up until ! "w has be5 uni=mly rais$ 9 temp]ature to ! desir$ po9t4 ,:5 mu* "w ( ! same g5]al "* & size is to be h&l$1 a p]man5t ov5 may be con/ruct$ ( fire brick1 leav+ a l>ge op5+ ?r\gh ! top & also ?r\gh "o side4 ,*>coal may be us$ 9 ?is =m ( ov5 z ) ! tempor>y arrangem5t1 or ! heat may be secur$ f any =m ( burn] or tor* giv+ a l>ge volume ( flame4 ,9 any me?od employ+ flame to d ! heat+1 ! "w itself mu/ be protect$ f ! direct bla/ ( ! fire4 ,baffles ( brick or metal %\ld be plac$ betwe5 ! m\? ( ! tor* & ! ne>e/ surface ( ! "w s t ! flame w be deflect$ to ei!r side & ar\nd ! piece be+ heat$4 ,! heat %\ld be appli$ to br+ ! po9t ( weld+ to ! highe/ temp]ature desir$ &1 except 9 ! smalle/ "w1 ! heat %\ld gradually %ade (f f ?is po9t to ! o!r p>ts ( ! piece4 ,9 ! case ( ca/ iron & /eel ! temp]ature at ! po9t to be weld$ %\ld be great en\gh to produce a dull r$ heat4 ,?is w make ! :ole op]ation mu* easi]1 because !re w be no surr\nd+ cool metal to r$uce ! temp]ature ( ! molt5 mat]ial f ! weld+ rod bel[ ! po9t at :i* x w jo9 ! "w4 ,f ?is r$ heat ! mass ( metal %\ld gr[ cool] z ! di/ance f ! weld becomes great]1 s t no great /ra9 is plac$ ^u any "o "p4 ,) "w ( a v irregul> %ape x is always be/ to heat ! entire piece s t ! /ra9s w be s ev5ly di/ribut$ t !y c cause no di/ortion or breakage "u any conditions4 ,! melt+ po9t ( ! "w :i* is be+ preheat$ %\ld be kept 9 m9d & c>e ex]cis$ n to approa* x too closely4 ,special c>e is necess>y ) alum9um 9 ?is respect1 because ( its l[ melt+ temp]ature & ! sudd5 weak5+ & fl[+ )\t w>n+4 ,workm5 h c>elessly ov]heat$ alum9um ca/+s &1 ^u uncov]+ ! piece to make ! weld1 h be5 a/oni%$ to f9d t x _h disappe>$4 ,six hundr$ degrees is ab\t ! safe limit = ?is metal4 ,x is possible to gauge ! exact temp]ature ( ! "w ) a pyromet]1 b :5 ?is in/rum5t _c be procur$1 x might be well to secure a numb] ( temp]ature cones f a *emical or laboratory supply h\se4 ,^! cones are made f mat]ial t w s(t5 at a c]ta9 heat & 9 =m !y are long & po9t$4 ,plac$ 9 position on ! "p be+ heat$1 ! po9t may be wat*$1 & :5 x b5ds ov] x is sure t ! metal itself has rea*$ a temp]ature consid]ably 9 excess ( ! temp]ature at :i* t p>ticul> cone 0 design$ to s(t54 ,! object 9 preheat+ ! metal ar\nd ! weld is to cause x to exp& suffici5tly to op5 ! crack a di/ance equal to ! contraction :5 cool+ f ! melt+ po9t4 ,9 ! case ( a crack runn+ f ! edge ( a piece into ! body or ( a crack :olly )9 ! body1 x is usually satisfactory to heat ! metal at ea* end ( ! op5+4 ,?is w cause ! :ole l5g? ( ! crack to op5 suffici5tly to receive ! molt5 mat]ial f ! rod4 ,! judgm5t ( ! op]ator w be call$ ^u to decide j :]e a piece ( metal %\ld be heat$ to op5 ! weld prop]ly4 ,x is (t5 possible to apply ! preheat+ flame to a po9t "s di/ance f ! po9t ( "w if ! p>ts are s connect$ t ! expansion ( ! heat$ "p w s]ve to draw ! edges ( ! weld ap>t4 ,:atev] "p ( ! "w is heat$ to cause expansion & sep>ation1 ?is "p mu/ rema9 hot dur+ ! entire "t ( weld+ & mu/ !n cool sl[ly at ! same "t z ! metal 9 ! weld cools4 ,illu/ration3 ,figure #be4--,preheat+ at ,a ,:ile ,weld+ at ,b4 ,c also ,may ,be ,heat$4 ,an example ( heat+ po9ts away f ! crack might be f\nd 9 weld+ a lattice "w ) "o ( ! b>s crack$ ?r\gh 7,figure #be74 ,if ! /rips p>allel & ne> to ! brok5 b> are heat$ gradually1 ! "w w be s exp&$ t ! edges ( ! break are drawn ap>t & ! weld c be successfully made4 ,9 ?is case1 ! p>allel b>s next to ! brok5 "o w\ld be heat$ highe/1 ! next r[ n q s hot & s on = "s di/ance away4 ,if only ! "o r[ 7 heat$1 ! /ra9s set up 9 ! next ones w\ld be suffici5t to cause a new break to appe>4 ,illu/ration3 ,figure #bf4--;,cutt+ ,?r\gh ! ,rim ( a ,:eel 7,cut ,%[n at ,a7 ,if weld+ is to be done ne> ! c5tral portion ( a l>ge piece1 ! /ra9s w be br\ght to be> on ! p>ts f>!/ away f ! c5t]4 ,%\ld a fly :eel spoke be brok5 & made ready to weld1 ! greate/ /ra9 w come on ! rim ( ! :eel4 ,9 cases l ?is x is (t5 desirable to cut ?r\gh at ! po9t ( greate/ /ra9 ) a saw or cutt+ tor*1 all[+ free movem5t :ile ! weld is made at ! orig9al break 7,figure #bf74 ,aft] ! inside weld is complet$1 ! cut may be weld$ )\t dang]1 = ! reason t x w always be at "s po9t at :i* sev]e /ra9s _c be set up by ! contraction ( ! cool+ metal4 ,illu/ration3 ,figure #bg4--,us+ a ,w$ge ,:ile ,weld+ ,9 mat]ials t w spr+ to "s ext5t )\t breakage1 t is1 9 p>ts t are n brittle1 x may be possible to =ce ! "w out ( %ape ) jacks or w$ges 7,figure #bg7 9 ! same way t x w\ld be di/ort$ by heat+ & exp&+ "s portion ( x z describ$4 ,a c>eful exam9ation w %[ :e!r ?is me?od c be foll[$ 9 su* a way z to =ce ! edges ( ! break to sep>ate4 ,if ! plan seems feasible1 ! w$ges may be put 9 place & all[$ to rema9 :ile ! weld is complet$4 ,z soon z ! "w is f9i%$ ! w$ges %\ld be remov$ s t ! natural contraction c take place )\t damage4 ,x %\ld always be rememb]$ t x is n s mu* ! expansion ( ! "w :5 heat$ z x is ! contraction caus$ by cool+ t w d ! damage4 ,a weld may be made t1 to all appe>ances1 is p]fect & x may be p]fect :5 complet$2 b if provision has n be5 made to all[ = ! contraction t is c]ta9 to foll[1 !re w be a breakage at "s po9t4 ,x is n possible to weld ! simple/ %apes1 o!r ?an /raight b>s1 )\t consid]+ ?is difficulty & mak+ provision to take c>e ( x4 ,! exact me?od to employ 9 preheat+ w always call = good judgm5t on ! "p ( ! workman1 & he %\ld rememb] t ! success or failure ( 8 "w w dep5d fully z mu* on prop] prep>ation z on correct h&l+ ( ! weld itself4 ,x %\ld be rememb]$ t ! out] flame ( ! oxy-acetyl5e tor* may be dep5d$ on = a c]ta9 am\nt ( preheat+1 z ?is flame gives a v l>ge volume ( heat1 b a heat t is n s int5se nor s localiz$ z ! weld+ flame itself4 ,! heat ( ?is "p ( ! flame %\ld be fully utiliz$ dur+ ! op]ation ( melt+ ! metal & x %\ld be s direct$1 :5 possible1 t x w br+ ! p>ts next to be jo9$ to z high a temp]ature z possible4 ,:5 ! "w has be5 br\ght to ! desir$ temp]ature1 all p>ts except ! break & ! surface imm$iately surr\nd+ x on bo? sides %\ld be cov]$ ) heavy %eet asbe/os4 ,?is protect+ cov] %\ld rema9 9 place ?r\gh\t ! op]ation & %\ld only be mov$ a di/ance suffici5t to all[ ! tor* flame to travel 9 ! pa? ( ! weld4 ,! use ( asbe/os 9 ?is way s]ves a tw(old purpose4 ,x reta9s ! heat 9 ! "w & prev5ts ! breakage t w\ld foll[ if a draught ( air 7 to /rike ! heat$ metal1 & x also prev5ts su* a radiation ( heat ?r\gh ! surr\nd+ air z w\ld make x almo/ impossible = ! op]ator to p]=m 8 "w1 especially 9 ! case ( l>ge & heavy ca/+s :5 ! am\nt ( heat utiliz$ is l>ge4 ,clean+ & ,*ampf]+4--,a p]fect weld c nev] be made unless ! surfaces to be jo9$ h be5 prop]ly prep>$ to receive ! new metal4 ,all spoil$1 burn$1 corrod$ & r\gh p>ticles mu/ positively be remov$ ) *isel & hamm] & ) a free application ( em]y clo? & wire bru%4 ,! metal expos$ to ! weld+ flame %\ld be p]fectly clean & bright all ov]1 or else ! additional mat]ial w n unite1 b w only /ick at be/4 ,illu/ration3 ,figure #bh4--,tap]+ ! ,op5+ ,=m$ by a ,break ,foll[+ ! clean+ x is always necess>y to bevel1 or *ampf]1 ! edges except 9 ! ?9ne/ %eet metal4 ,to make a weld t w hold1 ! metal mu/ be made into "o piece1 )\t holes or unfill$ portions at any po9t1 & mu/ be solid f inside to outside4 ,?is c only be accompli%$ by />t+ ! addition ( metal at "o po9t & gradually build+ x up until ! outside1 or top1 is rea*$4 ,) comp>atively ?9 plates ! molt5 metal may be />t$ f ! side f>!/ f ! op]ator & br\ght ?r\gh1 b ) ?ick] sections ! addition is />t$ 9 ! middle & br\ght flu% ) "o side & !n ) ! o!r4 ,x w readily be se5 t ! molt5 mat]ial _c be dep5d$ ^u to fl[ betwe5 ! tightly clos$ surfaces ( a crack 9 a way t c be at all sure to make a true weld4 ,x w be necess>y = ! op]ator to rea* to ! f>!/ side ) ! flame & weld+ rod1 & to />t ! new surfaces !re4 ,to all[ ?is1 ! edges t are to be jo9$ are bevel$ f "o side to ! o!r 7,figure #bh71 s t :5 plac$ toge!r 9 approximately ! position !y are to occupy !y w leave a groov$ *annel betwe5 !m ) its sides at an angle ) ea* o!r suffici5t 9 size to all[ access to e po9t ( ea* surface4 ,illu/ration3 ,figure #bi4--;,bevel+ = ,?9 ,"w ,illu/ration3 ,figure #cj4--;,bevel+ = ,?ick ,"w ,) "w less ?an "o-f\r? in* ?ick1 ?is angle %\ld be =ty-five degrees on ea* piece 7,figure #bi71 s t :5 !y are plac$ toge!r ! extreme edges w meet at ! bottom ( a groove ^: sides are squ>e1 or at "r angles1 to ea* o!r4 ,?is bevel+ %\ld be done s t only a ?9 edge is left :]e ! two p>ts come toge!r1 j en\gh po9ts 9 contact to make ! alignm5t easy to hold4 ,) "w ( a ?ickness great] ?an a qu>t] ( an in*1 ! angle ( bevel on ea* piece may be sixty degrees 7,figure #cj71 s t :5 plac$ toge!r ! angle includ$ betwe5 ! slop+ sides w also be sixty degrees4 ,if ! plate is less ?an "o-eigh? ( an in* ?ick ! bevel+ is n necess>y1 z ! edges may be melt$ all ! way ?r\gh )\t dang] ( leav+ bl[holes at any po9t4 ,illu/ration3 ,figure #ca4--;,bevel+ ,bo? ,sides ( a ,?ick ,piece ,illu/ration3 ,figure #cb4--;,bevel+ ! ,end ( a ,pipe ,?is bevel+ may be done 9 any conv5i5t way4 ,a *isel is usually mo/ satisfactory & also quicke/4 ,small sections may be h&l$ by fil+1 :ile metal t is too h>d to cut 9 ei!r ( ^! ways may be %ap$ on ! em]y :eel4 ,x is n necess>y t ! edges be p]fectly f9i%$ & absolutely smoo?1 b !y %\ld be ( regul> outl9e & %\ld always tap] (f to a ?9 edge s t :5 ! flame is fir/ appli$ x c be se5 issu+ f ! f> side ( ! crack4 ,if ! "w is q ?ick & is ( a %ape t w all[ x to be turn$ ov]1 ! bevel may be br\ght f bo? sides 7,figure #ca71 s t !re w be two grooves1 "o on ea* surface ( ! "w4 ,aft] complet+ ! weld on "o side1 ! piece is rev]s$ & f9i%$ on ! o!r side4 ,figure #cb %[s ! prop] bevel+ = weld+ pipe4 ,figure #cc %[s h[ %eet metal may be flang$ = weld+4 ,weld+ %\ld n be attempt$ ) ! edges sep>at$ 9 place ( bevel$1 because x w be f\nd impossible to build up a solid web ( new metal f "o side cle> ?r\gh to ! o!r by ?is me?od4 ,! flame _c rea* ! surfaces to make !m molt5 :ile receiv+ new mat]ial f ! rod1 & if ! flame does n rea* !m x w only s]ve to cause a few drops ( ! metal to jo9 & w surely cause a weak & defective weld4 ,illu/ration3 ,figure #cc4--;,flang+ ,%eet ,metal = ,weld+ ,support+ ,"w4--,dur+ ! op]ation ( weld+ x is necess>y t ! "w be well support$ 9 ! position x %\ld occupy4 ,?is may be done ) fire brick plac$ "u ! pieces 9 ! correct position1 or1 bett] /ill1 ) "s =m ( clamp4 ,! edges ( ! crack %\ld t\* ea* o!r at ! po9t :]e weld+ is to />t & f !re %\ld gradually sep>ate at ! rate ( ab\t "o-f\r? in* to ! foot4 ,?is is done s t ! cool+ ( ! molt5 metal z x is add$ w draw ! edges toge!r by its contraction4 ,c>e mu/ be us$ to see t ! "w is support$ s t x w ma9ta9 ! same relative position betwe5 ! p>ts z mu/ be pres5t :5 ! "w is f9i%$4 ,9 ?is connection x mu/ be rememb]$ t ! expansion ( ! metal :5 heat$ may be great en\gh to cause s]i\s di/ortion & to provide aga9/ ?is is "o ( ! difficulties to be ov]come4 ,p]fect alignm5t %\ld be secur$ betwe5 ! sep>ate p>ts t are to be jo9$ & ! two edges mu/ be held up s t !y w be 9 ! same plane :ile weld+ is c>ri$ out4 ,if1 by any *ance1 "o drops bel[ ! o!r :ile molt5 metal is be+ add$1 ! :ole job may h to be undone & done ov] aga94 ,"o precaution t is necess>y is t ( mak+ sure t ! clamp+ or support+ does n 9 itself pull ! "w out ( %ape :ile melt$4 ,,tor* ,,practice ,illu/ration3 ,figure #cd4--,rot>y ,movem5t ( ,tor* 9 ,weld+ ,! weld is made by br++ ! tip ( ! weld+ flame to ! edges ( ! metals to be jo9$4 ,! tor* %\ld be held 9 ! "r h& & mov$ sl[ly along ! crack ) a rotat+ motion1 travel+ 9 small circles 7,figure #cd71 s t ! ,weld+ flame t\*es fir/ on "o side ( ! crack & !n on ! o!r4 ,on l>ge "w ! motion may be simply back & =? across ! crack1 advanc+ regul>ly z ! metal unites4 ,x is usually be/ to weld t[>d ! op]ator r ?an f him1 al?\gh ?is rule is gov]n$ by circum/ances4 ,! head ( ! tor* %\ld be incl9$ at an angle ( ab\t #fj degrees to ! surface ( ! "w4 ,! tor* h&le %\ld ext5d 9 ! same l9e ) ! break 7,figure #ce7 & n across x1 except :5 weld+ v light plates4 ,illu/ration3 ,figure #ce4--,tor* ,held 9 ,l9e ) ! ,break ,if ! metal is #a_/af in* or less 9 ?ickness x is only necess>y to circle along ! crack1 ! metal itself furni%+ en\gh mat]ial to complete ! weld )\t additions4 ,heat bo? sides ev5ly until !y fl[ toge!r4 ,mat]ial ?ick] ?an ! above requires ! addition ( m metal ( ! same or diff]5t k9d f ! weld+ rod1 ?is rod be+ held by ! left h&4 ,! prop] size rod = ca/ iron is "o hav+ a diamet] equal to ! ?ickness ( metal be+ weld$ up to a "o-half in* rod1 :i* is ! l>ge/ us$4 ,= /eel ! rod %\ld be "o-half ! ?ickness ( ! metal be+ jo9$ up to "o-f\r? in* rod4 ,z a g5]al rule1 bett] results w be obta9$ by ! use ( small] rods1 ! v small sizes be+ twi/$ toge!r to furni% en\gh mat]ial :ile reta9+ ! free melt+ qualities4 ,illu/ration3 ,figure #cf4--,! ,weld+ ,rod ,%\ld ,be ,held 9 ! ,molt5 ,metal ,! tip ( ! rod mu/ at all times be held 9 contact ) ! pieces be+ weld$ & ! flame mu/ be s direct$ t ! two sides ( ! crack & ! end ( ! rod are melt$ at ! same "t 7,figure #cf74 ,be=e any?+ is add$ f ! rod1 ! sides ( ! crack are melt$ d[n suffici5tly to fill ! bottom ( ! groove & jo9 ! two sides4 ,aft]w>d1 z metal comes f ! rod 9 fill+ ! crack1 ! flame is circl$ along ! jo9t be+ made1 ! rod always foll[+ ! flame4 ,illu/ration3 ,figure #cg4--,weld+ ,pieces ( ,unequal ,?ickness ,figure #cg illu/rates ! weld+ ( pieces ( unequal ?ickness4 ,figure #ch illu/rates weld+ at an angle4 ,! molt5 metal may be direct$ z to :]e x %\ld g by ! tip ( ! weld+ flame1 :i* has consid]able =ce1 b c>e mu/ be tak5 n to bl[ melt$ metal on to cool] surfaces :i* x _c jo94 ,if1 :ile weld+1 a spot appe>s :i* does n unite ) ! weld1 x may be h&l$ by heat+ all ar\nd x to a :ite heat & !n imm$iately weld+ ! bad place4 ,illu/ration3 ,figure #ch4--,weld+ at an ,angle ,nev] /op 9 ! middle ( a weld1 z x is extremely difficult to cont9ue smoo?ly :5 resum+ "w4 ,! ,flame4--,! weld+ flame mu/ h exactly ! "r proportions ( ea* gas4 ,if !re is too mu* oxyg51 ! metal w be burn$ or oxidiz$2 ! pres5ce ( too mu* acetyl5e c>bonizes ! metal2 t is to say1 x adds c>bon & makes ! "w h>d]4 ,j ! "r mixture w nei!r burn nor c>bonize & is said to be a neutral flame4 ,! neutral flame1 if ( ! correct size = ! "w1 r$uces ! metal to a melt$ condition1 n too fluid1 & = a wid? ab\t ! same z ! ?ickness ( ! metal be+ weld$4 ,:5 ready to light ! tor*1 aft] atta*+ ! "r tip or head z direct$ 9 accordance ) ! ?ickness ( metal to be h&l$1 x w be necess>y to regulate ! pressure ( gases to secure ! neutral flame4 ,! oxyg5 w h a pressure ( f #b to #bj p\nds1 accord+ to ! nozzle us$4 ,! acetyl5e w h mu* less4 ,ev5 ) ! compress$ gas1 ! pressure %\ld nev] exce$ #aj p\nds = ! l>ge/ "w1 & x w usually be f #d to #f4 ,9 l[ pressure sy/ems1 ! acetyl5e w be receiv$ at g5]ator pressure4 ,x %\ld fir/ be se5 t ! h&-screws on ! regulators are turn$ way out s t ! spr+s are free f any t5sion4 ,x w d no h>m if ^! screws are turn$ back until !y come out ( ! ?reads4 ,?is mu/ be done ) bo? oxyg5 & acetyl5e regulators4 ,next1 op5 ! valve f ! g5]ator1 or on ! acetyl5e tank1 & c>efully note :e!r !re is any odor ( escap+ gas4 ,any leakage ( ?is gas mu/ be /opp$ be=e go+ on ) ! "w4 ,! h& :eel controll+ ! oxyg5 cyl9d] valve %\ld n[ be turn$ v sl[ly to ! left z f> z x w g1 :i* op5s ! valve1 & x %\ld be borne 9 m9d ! pressure t is be+ releas$4 ,turn 9 ! h& screw on ! oxyg5 regulator until ! small pressure gauge %[s a read+ accord+ to ! requirem5ts ( ! nozzle be+ us$4 ,?is oxyg5 regulator adju/m5t %\ld be made ) ! cock on ! tor* op51 & aft] ! regulator is ?us adju/$ ! tor* cock may be clos$4 ,op5 ! acetyl5e cock on ! tor* & screw 9 on ! acetyl5e regulator h&-screw until gas comm5ces to come ?r\gh ! tor*4 ,light ?is fl[ ( acetyl5e & adju/ ! regulator screw to ! pressure desir$1 or1 if !re is no gauge1 s t !re is a good full flame4 ,) ! pressure ( acetyl5e controll$ by ! type ( g5]ator x w only be necess>y to op5 ! tor* cock4 ,) ! acetyl5e burn+1 sl[ly op5 ! oxyg5 cock on ! tor* & all[ ?is gas to jo9 ! flame4 ,! flame w turn int5sely bright & !n blue :ite4 ,!re w be an out] flame f f\r to eight in*es long & f "o to ?ree in*es ?ick4 ,inside ( ?is flame w be two m r di/9ctly def9$ flames4 ,! inn] "o at ! tor* tip is v small1 & ! int]m$iate "o is long & po9t$4 ,! oxyg5 %\ld be turn$ on until ! two inn] flames unite into "o blue-:ite cone f "o-f\r? to "o-half in* long & "o-eigh? to "o-f\r? in* 9 diamet]4 ,if ?is s+le1 cle>ly def9$ cone does n appe> :5 ! oxyg5 tor* cock has be5 fully op5$1 turn (f "s ( ! acetyl5e until x does appe>4 ,if too mu* oxyg5 is add$ to ! flame1 !re w /ill be ! c5tral blue-:ite cone1 b x w be small] & m or less ragg$ ar\nd ! edges 7,figure #ci74 ,:5 !re is j en\gh oxyg5 to make ! s+le cone1 & :51 by turn+ on m acetyl5e or by turn+ (f oxyg51 two cones are caus$ to appe>1 ! flame is neutral 7,figure #dj71 & ! small blue-:ite cone is call$ ! weld+ flame4 ,illu/ration3 ,figure #ci4--,oxidiz+ ,flame--,too ,mu* ,oxyg5 ,illu/ration3 ,figure #dj4--,neutral ,flame ,illu/ration3 ,figure #da4--,r$uc+ ,flame--,%[+ an ,excess ( ,acetyl5e ,:ile weld+1 te/ ! correctness ( ! flame adju/m5t occasionally by turn+ on m acetyl5e or by turn+ (f "s oxyg5 until two flames or cones appe>4 ,!n regulate z be=e to secure ! s+le di/9ct cone4 ,too mu* oxyg5 is n usually s h>mful z too mu* acetyl5e1 except ) alum9um4 7,see ,figure #da47 ,an excessive am\nt ( sp>ks com+ f ! weld d5otes t !re is too mu* oxyg5 9 ! flame4 ,%\ld ! op5+ 9 ! tip become p>tly clogg$1 x w be difficult to secure a neutral flame & ! tip %\ld be clean$ ) a brass or copp] wire--nev] ) iron or /eel tools or wire ( any k9d4 ,:ile ! tor* is do+ its "w1 ! tip may become excessively hot due to ! heat radiat$ f ! molt5 metal4 ,! tip may be cool$ by turn+ (f ! acetyl5e & dipp+ 9 wat] ) a slight fl[ ( oxyg5 ?r\gh ! nozzle to prev5t wat] f9d+ its way into ! mix+ *amb]4 ,! regulators = cutt+ are simil> to ^? = weld+1 except t high] pressures may be h&l$1 & !y are fitt$ ) gauges read+ up to #bjj or #bej p\nds pressure4 ,9 weld+ metals :i* conduct ! heat v rapidly x is necess>y to use a mu* l>g] nozzle & flame ?an = metals :i* h n ?is prop]ty4 ,?is peculi>ity is f\nd to ! greate/ ext5t 9 copp]1 alum9um & brass4 ,%\ld a hole be bl[n ?r\gh ! "w1 x may be clos$ by )draw+ ! flame = a few seconds & !n comm5c+ to build additional metal ar\nd ! edges1 work+ all ! way ar\nd & f9ally clos+ ! small op5+ left at ! c5t] ) a drop or two f ! weld+ rod4 ,,weld+ ,,v>i\s ,,metals ,because ( ! v>y+ melt+ po9ts1 rates ( expansion & contraction1 & o!r peculi>ities ( diff]5t metals1 x is necess>y to give detail$ consid]ation to ! mo/ important ones4 ,*>act]i/ics ( ,metals4--,! weld] %\ld ?or\ghly und]/& ! peculi>ities ( ! v>i\s metals ) :i* he has to deal4 ,! metals & _! alloys are describ$ "u ?is head+ 9 ! fir/ *apt] ( ?is book & a tabulat$ li/ ( ! mo/ important po9ts relat+ to ea* metal w be f\nd at ! end ( ! pres5t *apt]4 ,all ?is in=mation %\ld be not$ by ! op]ator ( a weld+ in/allation be=e comm5c+ actual "w4 ,because ( ! nature ( weld+1 ! melt+ po9t ( a metal is ( great importance4 ,a metal melt+ at a l[ temp]ature %\ld h m c>eful treatm5t to avoid undesir$ fl[ ?an "o :i* melts at a temp]ature :i* is relatively high4 ,:5 two dissimil> metals are to be jo9$1 ! "o :i* melts at ! high] temp]ature mu/ be act$ ^u by ! flame fir/ & :5 x is 9 a molt5 condition ! heat conta9$ 9 x w 9 _m cases be suffici5t to cause fusion ( ! l[] melt+ metal & all[ !m to unite )\t play+ ! flame on ! l[] metal to any great ext5t4 ,! heat conductivity be>s a v important relation to weld+1 inasmu* z a metal ) a high rate ( conductance requires m protection f cool+ air curr5ts & heat radiation ?an "o n hav+ ?is quality to su* a m>k$ ext5t4 ,a metal :i* conducts heat rapidly w require a l>g] volume ( flame1 a l>g] nozzle1 ?an o!rwise1 ?is be+ necess>y to supply ! additional heat tak5 away f ! weld+ po9t by ?is conductance4 ,! relative rates ( expansion ( ! v>i\s metals "u heat %\ld be und]/ood 9 ord] t p>ts made f su* mat]ial may h prop] prep>ation to comp5sate = ?is expansion & contraction4 ,p>ts made f metals hav+ widely v>y+ rates ( expansion mu/ h special treatm5t to all[ = ?is quality1 o!rwise breakage is sure to occur4 ,ca/ ,iron4--,all spoil$ metal %\ld be cut away & if ! "w is m ?an "o-eigh? in* 9 ?ickness ! sides ( ! crack %\ld be bevel$ to a #de degree angle1 leav+ a numb] ( po9ts t\*+ at ! bottom ( ! bevel s t ! "w may be jo9$ 9 its orig9al relation4 ,! entire piece %\ld be preheat$ 9 a brick$-up ov5 or ) *>coal plac$ on ! =ge1 :5 size does n w>rant build+ a tempor>y ov54 ,! entire piece %\ld be sl[ly heat$ & ! portion imm$iately surr\nd+ ! weld %\ld be br\ght to a dull r$4 ,c>e %\ld be us$ t ! heat does n w>p ! metal ?r\gh application to "o "p m ?an ! o!rs4 ,aft] weld+1 ! "w %\ld be sl[ly cool$ by cov]+ ) a%es1 slak$ lime1 asbe/os fibre or "s o!r non-conductor ( heat4 ,^! precautions are absolutely ess5tial 9 ! case ( ca/ iron4 ,a neutral flame1 f a nozzle proportion$ to ! ?ickness ( ! "w1 %\ld be held ) ! po9t ( ! blue-:ite cone ab\t "o-eigh? in* f ! surface ( ! iron4 ,a ca/ iron rod ( correct diamet]1 usually made ) an excess ( silicon1 is us$ by keep+ its end 9 contact ) ! molt5 metal & fl[+ x into ! puddle =m$ at ! po9t ( fusion4 ,metal %\ld be add$ s t ! weld /&s ab\t "o-eigh? in* above ! surr\nd+ surface ( ! "w4 ,v>i\s =ms ( flux may be us$ & !y are appli$ by dipp+ ! end ( ! weld+ rod into ! p[d] at int]vals4 ,^! p[d]s may conta9 borax or salt1 & to prev5t a h>d1 brittle weld1 graphite or f]ro-silicon may be add$4 ,flux %\ld be add$ only aft] ! iron is molt5 & z little z possible %\ld be us$4 ,no flux %\ld be us$ j be=e completion ( ! "w4 ,! weld+ flame %\ld be play$ on ! "w ar\nd ! crack & gradually br\ght to be> on ! "w4 ,! bottom ( ! bevel %\ld be jo9$ fir/ & x w be not$ t ! ca/ iron t5ds to run t[>d ! flame1 b does n /ick toge!r easily4 ,a h>d & por\s weld %\ld be c>efully gu>d$ aga9/1 z describ$ above1 & ^u completion ( ! "w ! weld$ surface %\ld be scrap$ ) a file1 :ile /ill r$ hot1 9 ord] to remove ! surface scale4 ,malleable ,iron4--,?is mat]ial %\ld be bevel$ 9 ! same way t ca/ iron is h&l$1 & preheat+ & sl[ cool+ are equally desirable4 ,! flame us$ is ! same z = ca/ iron & s is ! flux4 ,! weld+ rod may be ( ca/ iron1 al?\gh bett] results are secur$ ) ,norway iron wire or else a mild /eel wire wrapp$ ) a coil ( copp] wire4 ,x w be und]/ood t malleable iron turns to ord9>y ca/ iron :5 melt$ & cool$4 ,welds 9 malleable iron are usually f> f satisfactory & a bett] jo9t is secur$ by braz+ ! edges toge!r ) bronze4 ,! edges to be jo9$ are br\ght to a heat j a little bel[ ! po9t at :i* !y w fl[ & ! op5+ is !n quickly-fill$ f a rod ( ,tob9 bronze or manganese bronze1 a brass or bronze flux be+ us$ 9 ?is "w4 ,wr\ght ,iron or ,semi-,/eel4--,?is metal %\ld be bevel$ & heat$ 9 ! same way z describ$ = ca/ iron4 ,! flame %\ld be neutral1 ( ! same size z = /eel1 & us$ ) ! tip ( ! blue-:ite cone j t\*+ ! "w4 ,! weld+ rod %\ld be ( mild /eel1 or1 if wr\ght iron is to be weld$ to /eel1 a ca/ iron rod may be us$4 ,a ca/ iron flux is well suit$ = ?is "w4 ,x %\ld be not$ t wr\ght iron turns to ord9>y ca/ iron if kept heat$ = any l5g? ( "t4 ,/eel4--,/eel %\ld be bevel$ if m ?an "o-eigh? in* 9 ?ickness4 ,x requires only a local preheat+ ar\nd ! po9t to be weld$4 ,! weld+ flame %\ld be absolutely neutral1 )\t excess ( ei!r gas4 ,if ! metal is "o-sixte5? in* or less 9 ?ickness1 ! tip ( ! blue-:ite cone mu/ be held a %ort di/ance f ! surface ( ! "w2 9 all o!r cases ! tip ( ?is cone is t\*$ to ! metal be+ weld$4 ,! weld+ rod may be ( mild1 l[ c>bon /eel or ( ,norway iron4 ,nickel /eel rods may be us$ = p>ts requir+ great /r5g?1 b vanadium alloys are v difficult to h&le4 ,a v satisfactory rod is made by twi/+ toge!r two wires ( ! requir$ mat]ial4 ,! rod mu/ be kept con/antly 9 contact ) ! "w & %\ld n be add$ until ! edges are ?or\ghly melt$4 ,! flux may or may n be us$4 ,if "o is want$1 x may be made f ?ree p>ts iron fil+s1 six p>ts borax & "o "p sal ammoniac4 ,x w be notic$ t ! /eel runs f ! flame1 b t5ds to hold toge!r4 ,%\ld foam+ comm5ce 9 ! molt5 metal1 x %[s an excess ( oxyg5 & t ! metal is be+ burn$4 ,high c>bon /eels are v difficult to h&le4 ,x is claim$ t a drop or two ( copp] add$ to ! weld w assi/ ! fl[1 b w also h>d5 ! "w4 ,an excess ( oxyg5 r$uces ! am\nt ( c>bon & s(t5s ! /eel1 :ile an excess ( acetyl5e increases ! proportion ( c>bon & h>d5s ! metal4 ,high spe$ /eels may sometimes be weld$ if fir/ coat$ ) semi-/eel be=e weld+4 ,alum9um4--,?is is ! mo/ difficult ( ! commonly f\nd metals to weld4 ,?is is caus$ by its high rate ( expansion & contraction & its liability to melt & fall away f "u ! flame4 ,! alum9um seems to melt on ! inside fir/1 &1 )\t previ\s w>n+1 a portion ( ! "w w simply vani% f 9 front ( ! op]ator's eyes4 ,! metal t5ds to run f ! flame & sep>ate at ! same "t4 ,to keep ! metal 9 %ape & free f oxide1 x is work$ or puddl$ :ile 9 a pla/ic condition by an iron rod :i* has be5 flatt5$ at "o end4 ,sev]al ( ^! rods %\ld be at h& & may be kept 9 a j> ( salt wat] :ile n be+ us$4 ,^! rods mu/ n become coat$ ) alum9um & !y mu/ n get r$ hot :ile 9 ! weld4 ,! surfaces to be jo9$1 toge!r ) ! adjac5t p>ts1 %\ld be clean$ ?or\ghly & !n wa%$ ) a #be p] c5t solution ( nitric acid 9 hot wat]1 us$ on a swab4 ,! p>ts %\ld !n be r9s$ 9 clean wat] & dri$ ) sawdu/4 ,x is also well to make tempor>y fire clay m\lds back ( ! p>ts to be heat$1 s t ! metal may be fl[$ into place & all[$ to cool )\t dang] ( breakage4 ,alum9um mu/ inv>iably be preheat$ to ab\t #fjj degrees1 & ! :ole piece be+ h&l$ %\ld be well cov]$ ) %eet asbe/os to prev5t excessive heat radiation4 ,! flame is =m$ ) an excess ( acetyl5e su* t ! second cone ext5ds ab\t an in*1 or slightly m1 beyond ! small blue-:ite po9t4 ,! tor* %\ld be held s t ! end ( ?is second cone is 9 contact ) ! "w1 ! small cone ord9>ily us$ be+ kept an in* or an in* & a half f ! surface ( ! "w4 ,weld+ rods ( special alum9um are us$ & mu/ be h&l$ ) _! end subm]g$ 9 ! molt5 metal ( ! weld at all times4 ,:5 alum9um is melt$ x =ms alum9a1 an oxide ( ! metal4 ,?is alum9a surr\nds small masses ( ! metal1 & z x does n melt at temp]atures bel[ #ejjj degrees 7:ile alum9um melts at ab\t #abjj71 x prev5ts a weld f be+ made4 ,! =mation ( ?is oxide is ret>d$ & ! oxide itself is dissolv$ by a suitable flux1 :i* usually conta9s phosphorus to break d[n ! alum9a4 ,copp]4--,! :ole piece %\ld be preheat$ & kept well cov]$ :ile weld+4 ,! flame mu/ be mu* l>g] ?an = ! same ?ickness ( /eel & neutral 9 "*4 ,a slight excess ( acetyl5e w\ld be pref]able to an excess ( oxyg51 & 9 all cases ! molt5 metal %\ld be kept envelop$ ) ! flame4 ,! weld+ rod is ( copp] :i* conta9s phosphorus2 & a flux1 also conta9+ phosphorus1 %\ld be spread = ab\t an in* ea* side ( ! jo9t4 ,^! assi/ 9 prev5t+ oxidation1 :i* is sure to occur ) heat$ copp]4 ,copp] breaks v easily at a heat slightly "u ! weld+ temp]ature & aft] cool+ x is simply ca/ copp] 9 all cases4 ,brass & ,bronze4--,x is necess>y to preheat ^! metals1 al?\gh n to a v high temp]ature4 ,!y mu/ be kept well cov]$ at all times to prev5t undue radiation4 ,! flame %\ld be produc$ ) a nozzle "o size l>g] ?an = ! same ?ickness ( /eel & ! small blue-:ite cone %\ld be held f "o-f\r? to "o-half in* above ! surface ( ! "w4 ,! flame %\ld be neutral 9 "*4 ,a rod or wire ( s(t brass conta9+ a l>ge p]c5tage ( z9c is suitable = add+ to brass1 :ile copp] requires ! use ( copp] or manganese bronze rods4 ,special flux or borax may be us$ to assi/ ! fl[4 ,! emission ( :ite smoke indicates t ! z9c conta9$ 9 ^! alloys is be+ burn$ away & ! heat %\ld imm$iately be turn$ away or r$uc$4 ,! fumes f brass & bronze weld+ are v poison\s & %\ld n be brea!d4 ,,re/oration ,,( ,,/eel ,! result ( ! high heat to :i* ! /eel has be5 subject$ is t x is weak5$ & ( a diff]5t "* ?an be=e weld+4 ,! op]ator may avoid ?is z mu* z possible by fir/ play+ ! out] flame ( ! tor* all ov] ! surfaces ( ! "w j complet$ until ^! faces are all ( uni=m color1 aft] :i* ! metal %\ld be well cov]$ ) asbe/os & all[$ to cool )\t be+ di/urb$4 ,if a tempor>y heat+ ov5 has be5 employ$1 ! "w & ov5 %\ld be all[$ to cool toge!r :ile protect$ ) ! %eet asbe/os4 ,if ! outside air /rikes ! fre%ly weld$ "w1 ev5 = a mom5t1 ! result w be breakage4 ,a weld 9 /eel w always leave ! metal ) a co>se gra9 & ) all ! *>act]i/ics ( r l[ grade ca/ /eel4 ,z previ\sly m5tion$ 9 ano!r *apt]1 ! l>g] ! gra9 size 9 /eel ! weak] ! metal w be1 & x is ! purpose ( ! good workman to avoid1 z f> z possible1 ?is weak5+4 ,! /ructure ( ! metal 9 "o piece ( /eel w diff] accord+ to ! heat t x has "u gone4 ,! p>ts ( ! "w t h be5 at ! melt+ po9t w1 !re=e1 h ! l>ge/ gra9 size & ! lea/ /r5g?4 ,^? p>ts t h n suff]$ any great rise 9 temp]ature w be practically unaffect$1 & all ! p>ts betwe5 ^! two extremes w be weak] or /rong] accord+ to _! di/ance f ! weld itself4 ,to re/ore ! /eel s t x w h ! be/ gra9 size1 ! op]ator may resort to ei!r ( two me?ods3 7#a7 ,! gra9 may be improv$ by =g+4 ,t means t ! metal add$ to ! weld & ! surfaces t h be5 at ! weld+ heat are hamm]$ mu* z a blacksmi? w\ld hamm] 8 f9i%$ "w to give x great] /r5g?4 ,! hamm]+ %\ld cont9ue f ! "t ! metal fir/ />ts to cool until x has rea*$ ! temp]ature at :i* ! gra9 size is be/ = /r5g?4 ,?is temp]ature w v>y some:at ) ! composition ( ! metal be+ h&l$1 b 9 a g5]al way1 x may be /at$ t ! hamm]+ %\ld cont9ue )\t int]mission f ! "t ! flame is remov$ f ! weld until ! /eel j beg9s to %[ attraction = a magnet pres5t$ to x4 ,?is temp]ature ( magnetic attraction w always be l[ en\gh & ! hamm]+ %\ld be imm$iately discont9u$ at ?is po9t4 7#b7 ,a me?od t is m satisfactory1 al?\gh h>d] to apply1 is t ( reheat+ ! /eel to a c]ta9 temp]ature ?r\gh\t its :ole mass :]e ! heat has _h any effect1 & !n all[+ sl[ & ev5 cool+ f ?is temp]ature4 ,! gra9 size is affect$ by ! temp]ature at :i* ! reheat+ is /opp$1 & n by ! cool+1 yet ! cool+ %\ld be sl[ en\gh to avoid /ra9s caus$ by unev5 contraction4 ,aft] ! weld has be5 complet$ ! /eel mu/ be all[$ to cool until bel[ #abjj ,fahr5heit4 ,! next /ep is to heat ! "w sl[ly until all ^? p>ts to be re/or$ h rea*$ a temp]ature at :i* ! magnet j ceases to be attract$4 ,:ile ! v be/ temp]ature w v>y accord+ to ! nature & h>dness ( ! /eel be+ h&l$1 x w be safe to c>ry ! heat+ to ! po9t indicat$ by ! magnet 9 ! abs5ce ( suitable means ( measur+ accurately ^! high temp]atures4 ,9 us+ a magnet = te/+1 x w be mo/ satisfactory if x is an electromagnet & n ( ! p]man5t type4 ,! electric curr5t may be secur$ f any small batt]y & w be ! means ( mak+ sure ( ! te/4 ,! p]man5t magnet w quickly lose its p[] ( attraction "u ! comb9$ action ( ! heat & ! j>r+ to :i* x w be subject$4 ,9 reheat+ ! "w x is necess>y to make sure t no "p rea*es a temp]ature above t desir$ = be/ gra9 size & also to see t all p>ts are br\ght to ?is temp]ature4 ,"h ent]s ! greate/ difficulty 9 re/or+ ! metal4 ,! heat+ may be done s sl[ly t no "p ( ! "w on ! outside rea*es too high a temp]ature & !n keeps ! outside at ?is heat until ! entire mass is at ! same temp]ature4 ,a less desirable way is to heat ! outside high] ?an ?is temp]ature & all[ ! conductivity ( ! metal to di/ribute ! excess to ! inside4 ,! mo/ satisfactory me?od1 :]e x c be employ$1 is to make use ( a ba? ( "s molt5 metal or "s *emical mixture t c be kept at ! exact heat necess>y by means ( gas fires t admit ( close regulation4 ,! temp]ature ( ^! ba?s may be ma9ta9$ at a con/ant po9t by wat*+ a pyromet]1 & ! f9i%$ "w may be all[$ to rema9 9 ! ba? until all p>ts h rea*$ ! desir$ temp]ature4 ,,weld+ ,,in=mation ,! foll[+ tables include mu* ( ! in=mation t ! op]ator mu/ use cont9ually to h&le ! v>i\s metals successfully4 ,! temp]ature scales are giv5 = conv5i5ce only4 ,! composition ( v>i\s alloys w give an idea ( ! difficulties to be cont5d$ ) by consult+ ! in=mation on weld+ v>i\s metals4 ,! rema9+ tables are ( self-evid5t value 9 ?is "w4 ,,temp]ature ,,scales ,c5tigrade ,fahr5heit ,c5tigrade ,fahr5heit #bjj #cib #ajjj #ahcb #bbe #dcg #ajej #aibb #bej #dhb #aajj #bjab #bge #ebg #aaej #bajb #cjj #egb #abjj #baib #cbe #fag #abej #bbhb #cej #ffb #acjj #bcgb #cge #gjg #acej #bdfb #djj #geb #adjj #beeb #dbe #gig #adej #bfdb #dej #hdb #aejj #bgcb #dge #hhg #aeej #bhbb #ejj #icb #afjj #biab #ebe #igg #afej #cjjb #eej #ajbb #agjj #cjib #ege #ajfg #agej #cahb #fjj #aaab #ahjj #cbgb #fbe #aaeg #ahej #ccfb #fej #abjb #aijj #cdeb #fge #abdg #bjjj #cfcb #gjj #abib #bjej #cgbb #gbe #accg #bajj #chab #gej #achb #baej #cijb #gge #adbg #bbjj #ciib #hjj #adgb #bbej #djhb #hbe #aeag #bcjj #dagb #hej #aefb #bcej #dbfb #hge #afjg #bdjj #dceb #ijj #afeb #bdej #dddb #ibe #afig #bejj #decb #iej #agdb #beej #dfbb #ige #aghg #bfjj #dgab ,,metal ,,alloys 7,society ( ,automobile ,eng9e]s7 ,babbitt-- ,t9444444444444444444444444444 #hd4jj ,antimony4444444444444444444444 #i4jj ,copp]444444444444444444444444 #g4jj ,brass1 ,:ite-- ,copp]444444444444444444444444 #c4jj to #f4jj ,t9 7m9imum7 4444444444444444 #fe4jj ,z9c44444444444444444444444444 #bh4jj to #cj4jj ,brass1 ,r$ ,ca/-- ,copp]444444444444444444444444 #he4jj ,t9444444444444444444444444444 #e4jj ,lead44444444444444444444444444 #e4jj ,z9c44444444444444444444444444 #e4jj ,brass1 ,yell[-- ,copp]444444444444444444444444 #fb4jj to #fe4jj ,lead44444444444444444444444444 #b4jj to #d4jj ,z9c44444444444444444444444444 #cf4jj to #ca4jj ,bronze1 ,h>d-- ,copp]444444444444444444444444 #hg4jj to #hh4jj ,t9444444444444444444444444444 #i4ej to #aj4ej ,z9c44444444444444444444444444 #a4ej to #b4ej ,bronze1 ,phosphor-- ,copp]444444444444444444444444 #hj4jj ,t9444444444444444444444444444 #aj4jj ,lead44444444444444444444444444 #aj4jj ,phosphorus44444444444444444444 4#ej to 4#be ,bronze1 ,manganese-- ,copp] 7approximate7 444444444 #fj4jj ,z9c 7approximate7 44444444444 #dj4jj ,manganese 7v>iable7 444444444 small ,bronze1 ,ge>-- ,copp]444444444444444444444444 #hh4jj to #hi4jj ,t9444444444444444444444444444 #aa4jj to #ab4jj ,alum9um ,alloys-- ,alum9um ,copp] ,z9c ,manganese ,no4 #a44 #ij4jj #h4e-g4j ,no4 #b44 #hj4jj #b4j-c4j #ae ,n ov] #j4dj ,no4 #c44 #fe4jj #ce4j ,ca/ ,iron-- ,gray ,iron ,malleable ,total c>bon44444444#c4j to #c4e ,comb9$ c>bon44444#j4d to #j4g ,manganese44444444444#j4d to #j4g #j4c to #j4g ,phosphorus4444444444#j4f to #a4j ,n ov] #j4b ,sulphur44444444444,n ov] #j4a ,n ov] #j4f ,silicon444444444444#a4ge to #b4be ,n ov] #a4j ,c>bon ,/eel 7#aj ,po9t7-- ,c>bon444444444444444444444444 4#je to 4#ae ,manganese444444444444444444444 4#cj to 4#fj ,phosphorus 7maximum74444444444 4#jde ,sulphur 7maximum74444444444444 4#je 7#bj ,po9t7-- ,c>bon444444444444444444444444 4#ae to 4#be ,manganese444444444444444444444 4#cj to 4#fj ,phosphorus 7maximum74444444444 4#jde ,sulphur 7maximum74444444444444 4#je 7#ce ,po9t7-- ,manganese444444444444444444444 4#ej to 4#hj ,c>bon444444444444444444444444 4#cj to 4#dj ,phosphorus 7maximum74444444444 4#je ,sulphur 7maximum74444444444444 4#je 7#ie ,po9t7-- ,c>bon444444444444444444444444 4#ij to #a4je ,manganese444444444444444444444 4#be to 4#ej ,phosphorus 7maximum74444444444 4#jd ,sulphur 7maximum74444444444444 4#je ,,heat+ ,,p[] ,,( ,,fuel ,,gases 7,9 ,b4,t4,u4 p] ,cubic ,foot47 ,acetyl5e4444444 #adih4ii ,e?yl5e4444444 #aefb4i ,hydrog544444444 #bia4if ,me?ane44444444 #iec4f ,alcohol444444444 #aeja4gf ,,melt+ ,,po9ts ,,( ,,metals ,plat9um44444444444444444444#cbjj ,iron1 wr\ght444444444444444#bijj malleable44444444444444444#bejj ca/4444444444444444444444#bdjj pure4444444444444444444444#bgfj ,/eel1 mild44444444444444444#bgjj ,m$ium44444444444444444444#bfjj ,h>d4444444444444444444444#bejj ,copp]4444444444444444444444#aiej ,brass44444444444444444444444#ahjj ,silv]4444444444444444444444#agej ,bronze4444444444444444444444#agjj ,alum9um44444444444444444444#aage ,antimony44444444444444444444#aaej ,z9c444444444444444444444444 #hjj ,lead444444444444444444444444 #fbj ,babbitt444444444444444444#ejj-gjj ,sold]4444444444444444444#ejj-ege ,t94444444444444444444444444 #dej ,,note4--,^! melt+ po9ts are = av]age compositions & conditions4 ,! exact proportion ( elem5ts ent]+ into ! metals affects _! melt+ po9ts "o way or ! o!r 9 practice4 ,,t5sile ,,/r5g? ,,( ,,metals ,alloy /eels c be made ) t5sile /r5g?s z high z #cjj1jjj p\nds p] squ>e in*4 ,"s c>bon /eels are giv5 bel[ accord+ to po9ts3 ,p\nds p] ,squ>e ,in* ,/eel1 #aj po9t4444444444444444 #ej1jjj to #fe1jjj #bj po9t444444444444444444444 #fj1jjj to #hj1jjj #dj po9t444444444444444444444 #gj1jjj to #ajj1jjj #fj po9t444444444444444444444 #ij1jjj to #abj1jjj ,iron1 ,ca/444444444444444444444 #ac1jjj to #cj1jjj ,wr\ght4444444444444444444444 #dj1jjj to #fj1jjj ,malleable44444444444444444444 #be1jjj to #de1jjj ,copp]4444444444444444444444444 #bd1jjj to #ej1jjj ,bronze4444444444444444444444444 #cj1jjj to #fj1jjj ,brass1 ,ca/44444444444444444444 #ab1jjj to #ah1jjj ,roll$44444444444444444444444 #cj1jjj to #dj1jjj ,wire4444444444444444444444444 #fj1jjj to #ge1jjj ,alum9um44444444444444444444444 #ab1jjj to #bc1jjj ,z9c444444444444444444444444444 #e1jjj to #ae1jjj ,t94444444444444444444444444444 #c1jjj to #e1jjj ,lead444444444444444444444444444 #a1ejj to #b1ejj ,,conductivity ,,( ,,metals 7,bas$ on ! ,value ( ,silv] z #ajj7 ,heat ,electricity ,silv]44444444444444444444#ajj #ajj ,copp]44444444444444444444 #gd #ii ,alum9um444444444444444444 #ch #fc ,brass444444444444444444444 #bc #bb ,z9c4444444444444444444444 #ai #bi ,t944444444444444444444444 #ad #ae ,wr\ght ,iron44444444444444 #ab #af ,/eel444444444444444444444 #aa4e #ab ,ca/ ,iron44444444444444444 #aa #ab ,bronze44444444444444444444 #i #g ,lead4444444444444444444444 #h #i ,,weight ,,( ,,metals 7,p] ,cubic ,in*7 ,p\nds ,p\nds ,lead444444444444 4#daj ,wr\ght ,iron44444 4#bgh ,copp]4444444444 4#cbj ,t944444444444444 4#bfc ,bronze4444444444 4#cac ,ca/ ,iron44444444 4#bfj ,brass44444444444 4#cjj ,z9c4444444444444 4#beh ,/eel44444444444 4#bhc ,alum9um444444444 4#jic ,,expansion ,,( ,,metals 7,measur$ 9 ,?\s&?s ( an ,in* p] ,foot ( ,l5g? ,:5 ,rais$ #ajjj ,degrees 9 ,temp]ature7 ,in* ,in* ,lead444444444444 4#ahh ,brass444444444444 4#aae ,z9c444444444444 4#afh ,copp]44444444444 4#ajf ,alum9um44444444 4#adh ,/eel444444444444 4#jhc ,silv]4444444444 4#abi ,wr\ght ,iron44444 4#jgh ,bronze4444444444 4#aah ,ca/ ,iron44444444 4#jfh ,,*apt] ,,vi ,,electric ,,weld+ ,,resi/ance ,,me?od ,two di/9ct =ms ( electric weld+ app>atus are 9 use1 "o produc+ heat by ! resi/ance ( ! metal be+ treat$ to ! passage ( electric curr5t1 ! o!r us+ ! heat ( ! electric arc4 ,! resi/ance process is ( ! greate/ use 9 manufactur+ l9es :]e !re is a l>ge quantity ( "o k9d ( "w to d1 _m ?\s& pieces ( "o k9d1 = in/ance4 ,! arc me?od may be appli$ 9 practically any case :]e any o!r =m ( weld may be made4 ,! resi/ance process w be describ$ fir/4 ,x is a well kn[n fact t a poor conductor ( electricity w (f] s mu* resi/ance to ! fl[ ( electricity t x w heat4 ,copp] is a good conductor1 & a b> ( iron1 a comp>atively poor conductor1 :5 plac$ betwe5 heavy copp] conductors ( a weld]1 becomes heat$ 9 attempt+ to c>ry ! l>ge volume ( curr5t4 ,! degree ( heat dep5ds on ! am\nt ( curr5t & ! resi/ance ( ! conductor4 ,9 an electric circuit ! ends ( two pieces ( metal br\ght toge!r =m ! po9t ( greate/ resi/ance 9 ! electric circuit1 & ! abutt+ ends in/antly beg9 to heat4 ,! hott] ?is metal becomes1 ! great] ! resi/ance to ! fl[ ( curr5t2 consequ5tly1 z ! edges ( ! abutt+ ends heat1 ! curr5t is =c$ into ! adjac5t cool] p>ts1 until !re is a uni=m heat ?r\gh\t ! entire mass4 ,! heat is fir/ develop$ 9 ! int]ior ( ! metal s t x is weld$ !re z p]fectly z at ! surface4 ,illu/ration3 ,figure #db4--,spot ,weld+ ,ma*9e ,! electric weld] 7,figure #db7 is built to hold ! p>ts to be jo9$ betwe5 two heavy copp] dies or contacts4 ,a curr5t ( ?ree to five volts1 b ( v great volume 7amp]age71 is all[$ to pass across ^! dies1 & 9 go+ ?r\gh ! metal to be weld$1 heats ! edges to a weld+ temp]ature4 ,x may be expla9$ t ! voltage ( an electric curr5t measures ! pressure or =ce ) :i* x is be+ s5t ?r\gh ! circuit & has no?+ to d ) ! quantity or volume pass+4 ,amp]es measure ! rate at :i* ! curr5t is pass+ ?r\gh ! circuit & consequ5tly give a measure ( ! quantity :i* passes 9 any giv5 "t4 ,volts correspond to wat] pressure measur$ by p\nds to ! squ>e in*2 amp]es repres5t ! fl[ 9 gallons p] m9ute4 ,! l[ voltage us$ avoids all dang] to ! op]ator1 ?is pressure n be+ suffici5t to be felt ev5 ) ! h&s re/+ on ! copp] contacts4 ,curr5t is suppli$ to ! weld+ ma*9e at a high] voltage & l[] amp]age ?an is actually us$ betwe5 ! dies1 ! l[ voltage & high amp]age be+ produc$ by a trans=m] incorporat$ 9 ! ma*9e itself4 ,by means ( w9d+s ( suitable size wire1 ! outside curr5t may be receiv$ at voltages rang+ f #aaj to #eej & conv]t$ to ! l[ pressure ne$$4 ,! s\rce ( curr5t = ! resi/ance weld] mu/ be alt]nat+1 t is1 ! curr5t mu/ fir/ be negative 9 value & !n positive1 pass+ f "o extreme to ! o!r at rates v>y+ f #be to #acc times a second4 ,?is =m is kn[n z alt]nat+ curr5t1 z oppos$ to direct curr5t1 9 :i* !re is no *ang+ ( positive & negative4 ,! curr5t mu/ also be :at is kn[n z s+le phase1 t is1 a curr5t :i* rises f z]o 9 value to ! highe/ po9t z a positive curr5t & !n rec$es to z]o be=e ris+ to ! highe/ po9t ( negative value4 ,two-phase ( ?ree-phase curr5ts w\ld give two or ?ree positive impulses dur+ ?is "t4 ,z long z ! curr5t is s+le phase alt]nat+1 ! voltage & cycles 7numb] ( alt]nations p] second7 may be any?+ conv5i5t4 ,v>i\s voltages & cycles are tak5 c>e ( by specify+ all ^! po9ts :5 design+ ! trans=m] :i* is to h&le ! curr5t4 ,direct curr5t is n us$ because !re is no way ( r$uc+ ! voltage conv5i5tly )\t plac+ resi/ance wires 9 ! circuit & ?is uses p[] )\t produc+ useful "w4 ,direct curr5t may be *ang$ to alt]nat+ by hav+ a direct curr5t motor runn+ an alt]nat+ curr5t dynamo1 or ! *ange may be made by a rot>y conv]t]1 al?\gh ?is la/ me?od is n s satisfactory z ! fir/4 ,! voltage us$ 9 weld+ be+ s l[ to />t )1 x is absolutely necess>y t x be ma9ta9$ at ! correct po9t4 ,if ! s\rce ( curr5t supply is n ( ample capacity = ! weld] be+ us$1 x w be v h>d to avoid a fall ( voltage :5 ! curr5t is =c$ to pass ?r\gh ! high resi/ance ( ! weld4 ,! curr5t voltage = v>i\s "w is calculat$ accurately1 & ! effici5cy ( ! outfit dep5ds to a great ext5t on ! voltage be+ con/ant4 ,a simple te/ = fall ( voltage is made by connect+ an inc&esc5t electric lamp across ! supply l9es at "s po9t ne> ! weld]4 ,! lamp %\ld burn ) ! same brilliancy :5 ! weld is be+ made z at any o!r "t4 ,if ! lamp burns dim at any "t1 x indicates a drop 9 voltage1 & ?is condition %\ld be correct$4 ,! dynamo furni%+ ! alt]nat+ curr5t may be 9 ! same build+ ) ! weld] & op]at$ f a direct curr5t motor1 z m5tion$ above1 or op]at$ f any conv5i5t %aft+ or s\rce ( p[]4 ,:5 ! dynamo is a "p ( ! weld+ plant x %\ld be plac$ z close to ! weld+ ma*9e z possible1 because ! l5g? ( ! wire us$ affects ! voltage appreciably4 ,9 ord] to hold ! voltage con/ant1 ! ,tol$o ,electric ,weld] ,company has devis$ connections :i* include a rheo/at to ins]t a v>iable resi/ance 9 ! field w9d+s ( ! dynamo s t ! voltage may be increas$ by cutt+ ?is resi/ance out at ! prop] "t4 ,an auxili>y swit* is connect$ to ! weld] swit* s t bo? swit*es act toge!r4 ,:5 ! weld] swit* is clos$ 9 mak+ a weld1 t portion ( ! rheo/at resi/ance betwe5 two arms det]m9+ ! voltage is %ort circuit$4 ,?is l[]s ! resi/ance & ! field magnets ( ! dynamo are made /rong] s t additional voltage is provid$ to c>e = ! resi/ance 9 ! metal be+ heat$4 ,a typical ma*9e is %[n 9 ! accompany+ cut 7,figure #dc74 ,on top ( ! weld] are two jaws = hold+ ! ends ( ! pieces to be weld$4 ,! l[] "p ( ! jaws is rigid :ile ! top is br\ght d[n on top ( ! "w1 act+ z a clamp4 ,^! jaws c>ry ! copp] dies ?r\gh :i* ! curr5t ent]s ! "w be+ h&l$4 ,aft] ! "w is clamp$ betwe5 ! jaws1 ! upp] set is =c$ clos] to ! l[] set by a long compression lev]4 ,! curr5t be+ turn$ on ) ! surfaces ( ! "w 9 contact1 !y imm$iately heat to ! weld+ po9t :5 add$ pressure on ! lev] =ces !m toge!r & completes ! weld4 ,illu/ration3 ,figure #dc--,op]at+ ,p>ts ( a ,tol$o ,spot ,weld] ,illu/ration3 ,figure #dc;a4--,me?od ( ,te/+ ,electric ,weld] ,illu/ration3 ,figure #dd4--;,detail ( ,wat]-,cool$ ,spot ,weld+ ,head ,! trans=m] is c>ri$ 9 ! base ( ! ma*9e & on ! left-h& side is a regulator = controll+ ! voltage = v>i\s k9ds ( "w4 ,! clamps are appli$ by treadles conv5i5t to ! foot ( ! op]ator4 ,a treadle is provid$ :i* in/antly releases bo? jaws ^u ! completion ( ! weld4 ,"o or bo? ( ! copp] dies may be cool$ by a /ream ( wat] circulat+ ?r\gh x f ! city wat] ma9s 7,figure #dd74 ,! regulator & swit* give ! op]ator control ( ! heat1 any?+ f a dull r$ to ! melt+ po9t be+ easily obta9$ by movem5t ( ! lev] 7figure #de74 ,illu/ration3 ,figure #de4--,weld+ ,head ( a ,wat]-,cool$ ,weld] ,weld+4--,x is n necess>y to give ! metal to be weld$ any special prep>ation1 al?\gh :5 v ru/y or cov]$ ) scale1 ! ru/ & scale %\ld be remov$ suffici5tly to all[ good contact ( clean metal on ! copp] dies4 ,! clean] & bett] ! /ock1 ! less curr5t x takes1 & !re is less we> on ! dies4 ,! dies %\ld be kept firm & tight 9 _! hold]s to make a good contact4 ,all bolts & nuts fa/5+ ! electrical contacts %\ld be clean & tight at all times4 ,! scale may be remov$ f =g+s by imm]s+ !m 9 a pickl+ solution 9 a wood1 /one or lead-l9$ tank4 ,! solution is made ) five gallons ( comm]cial sulphuric acid 9 #aej gallons ( wat]4 ,to get ! quicke/ & be/ results f ?is me?od1 ! solution %\ld be kept z ne> ! boil+ po9t z possible by hav+ a coil ( extra heavy lead pipe runn+ inside ! tank & c>ry+ live /eam4 ,a v few m9utes 9 ?is ba? w remove ! scale & ! p>ts %\ld !n be wa%$ 9 runn+ wat]4 ,aft] ?is wa%+ !y %\ld be dipp$ into a ba? ( #ej p\nds ( unslak$ lime 9 #aej gallons ( wat] to neutralize any trace ( acid4 ,ca/ iron _c be comm]cially weld$1 z x is high 9 c>bon & silicon1 & passes sudd5ly f a cry/all9e to a fluid /ate :5 br\ght to ! weld+ temp]ature4 ,) /eel or wr\ght iron ! temp]ature mu/ be kept bel[ ! melt+ po9t to avoid injury to ! metal4 ,! metal mu/ be heat$ quickly & press$ toge!r ) suffici5t =ce to pu% all burnt metal out ( ! jo9t4 ,high c>bon /eel c be weld$1 b mu/ be anneal$ aft] weld+ to ov]come ! /ra9s set up by ! heat be+ appli$ at "o place4 ,good results are h>d to obta9 :5 ! c>bon runs z high z #ge po9ts1 & /eel ( ?is class c only be h&l$ by an exp]i5c$ op]ator4 ,if ! /eel is bel[ #be po9ts 9 c>bon cont5t1 good welds w always be ! result4 ,to weld high c>bon to l[ c>bon /eel1 ! /ock %\ld be clamp$ 9 ! dies ) ! l[ c>bon /ock /ick+ consid]ably fur!r out f ! die ?an ! high c>bon /ock4 ,nickel /eel welds readily1 ! nickel increas+ ! /r5g? ( ! weld4 ,iron & copp] may be weld$ toge!r by r$uc+ ! size ( ! copp] end :]e x comes 9 contact ) ! iron4 ,:5 weld+ copp] & brass ! pressure mu/ be less ?an :5 weld+ iron4 ,! metal is all[$ to actually fuse or melt at ! juncture & ! pressure mu/ be suffici5t to =ce ! burn$ metal out4 ,! curr5t is cut (f ! in/ant ! metal ends beg9 to s(t51 ?is be+ done by means ( an automatic swit* :i* op5s :5 ! s(t5+ ( ! metal all[s ! ends to come toge!r4 ,! pressure is appli$ to ! weld by hav+ ! slid+ jaw mov$ by a weight on ! end ( an arm4 ,copp] & brass require a l>g] volume ( curr5t at a l[] voltage ?an = /eel & iron4 ,! die faces are set ap>t ?ree times ! diamet] ( ! /ock = brass & f\r times ! diamet] = copp]4 ,light gauges ( %eet /eel c be weld$ to heavy gauges or to solid b>s ( /eel by spot weld+1 :i* w be describ$ lat]4 ,galvaniz$ iron c be weld$1 b ! z9c coat+ w be burn$ (f4 ,%eet /eel c be weld$ to ca/ iron1 b w pull ap>t1 te>+ out p>ticles ( ! iron4 ,%eet copp] & %eet brass may be weld$1 al?\gh ?is "w requires m exp]i5ce ?an ) iron & /eel4 ,"s grades ( %eet alum9um c be spot-weld$ if ! slight r\ghness left on ! surface "u ! die is n objectionable4 ,butt ,weld+4--,?is is ! process :i* jo9s ! ends ( two pieces ( metal z describ$ 9 ! =ego+ "p ( ?is *apt]4 ,! ends are 9 pla9 sight ( ! op]ator at all times & x c easily be se5 :5 ! metal rea*es ! weld+ heat & beg9s to s(t5 7,figure #df74 ,x is at ?is po9t t ! pressure mu/ be appli$ ) ! lev] & ! ends =c$ toge!r 9 ! weld4 ,illu/ration3 ,figure #df4--;,butt ,weld] ,! p>ts are plac$ 9 ! clamp+ jaws 7,figure #dg7 ) #a_/h to #a_/b in* ( metal ext5d+ beyond ! jaw4 ,! ends ( ! metal t\* ea* o!r & ! curr5t is turn$ on by means ( a swit*4 ,to raise ! ends to ! prop] heat requires f #c seconds = #a_/d-;in* rods to #ce seconds = a #a-a_/b-;in* b>4 ,?is me?od is applicable to metals hav+ practically ! same area ( metal to be br\ght into contact on ea* end4 ,:5 su* p>ts are =c$ toge!r a slight projection w be left 9 ! =m ( a f9 or an enl>g$ portion call$ an upset4 ,! degree ( heat requir$ = any "w is f\nd by mov+ ! h&le ( ! regulator "o way or ! o!r :ile te/+ sev]al p>ts4 ,:5 ?is sett+ is "r ! "w c cont9ue z long z ! same sizes are be+ h&l$4 ,illu/ration3 ,figure #dg4--;,clamp+ ,dies ( a ,butt ,weld] ,copp]1 brass1 tool /eel & all o!r metals t are h>m$ by high temp]atures mu/ be heat$ quickly & press$ toge!r ) suffici5t =ce to =ce all burn$ metal f ! weld4 ,9 case x is desir$ to make a weld 9 ! =m ( a capital lett] ,t1 x is necess>y to heat ! "p correspond+ to ! top b> ( ! ,t to a bright r$1 !n br+ ! l[] b> to ! pre-heat$ "o & aga9 turn on ! curr5t1 :5 a weld c be quickly made4 ,spot ,weld+4--,?is is a me?od ( jo9+ metal %eets toge!r at any desir$ po9t by a weld$ spot ab\t ! size ( a rivet4 ,x is done on a spot weld] by fus+ ! metal at ! po9t desir$ & at ! same in/ant apply+ suffici5t pressure to =ce ! p>ticles ( molt5 metal toge!r4 ,! dies are usually plac$ "o above ! o!r s t ! "w may re/ on ! l[] "o :ile ! upp] "o is br\ght d[n on top ( ! upp] %eet to be weld$4 ,"o ( ! dies is usually po9t$ slightly1 ! oppos+ "o be+ left flat4 ,! po9t$ die leaves a slight ind5tation on "o side ( ! metal1 :ile ! o!r side is left smoo?4 ,! dies may be rev]s$ s t ! outside surface ( any "w may be left smoo?4 ,! curr5t is all[$ to fl[ ?r\gh ! dies by a swit* :i* is clos$ aft] pressure is appli$ to ! "w4 ,!re is a limit to ! ?ickness ( %eet metal t c be weld$ by ?is process because ( ! fact t ! copp] rods c only c>ry a c]ta9 quantity ( curr5t )\t becom+ unduly heat$ !mselves4 ,ano!r reason is t x is difficult to make heavy sections ( metal t\* at ! weld+ po9t )\t excessive pressure4 ,lap weld+ is ! process us$ :5 two pieces ( metal are caus$ to ov]lap & :5 br\ght to a weld+ heat are =c$ toge!r by pass+ ?r\gh roll]s1 or "u a press1 ?us leav+ ! weld$ jo9t practically ! same ?ickness z ! balance ( ! "w4 ,:]e x is desirable to make a cont9u\s seam1 a special ma*9e is requir$1 or an atta*m5t = "o ( ! o!r types4 ,9 ?is =m ( "w ! /ock mu/ be ?or\ghly clean$ & is !n pass$ betwe5 copp] roll]s :i* act 9 ! same capacity z ! copp] dies4 ,o!r ,applications4--,h>d5+ & temp]+ c be done by clamp+ ! "w 9 ! weld+ dies & sett+ ! control & "t to br+ ! metal to ! prop] color1 :5 x is cool$ 9 ! usual mann]4 ,braz+ is done by clamp+ ! "w 9 ! jaws & heat+ until ! flux1 !n ! spelt] has melt$ & run into ! jo9t4 ,rivet+ & head+ ( rivets c be done by br++ ! dies d[n on opposite ends ( ! rivet aft] x has be5 ins]t$ 9 ! hole1 ! dies be+ %ap$ to =m ! heads prop]ly4 ,h>d5$ /eel may be s(t5$ & anneal$ s t x c be ma*9$ by connect+ ! dies ( ! weld] to ea* side ( ! po9t to be s(t5$4 ,! curr5t is !n appli$ until ! "w has rea*$ a po9t at :i* x w s(t5 :5 cool$4 ,tr\bles & ,rem$ies4--,! foll[+ me?ods h be5 furni%$ by ! ,tol$o ,electric ,weld] ,company & are recomm5d$ = ?is class ( "w :5ev] necess>y4 ,to locate gr\nds 9 ! prim>y or high voltage side ( ! circuit1 connect inc&esc5t lamps 9 s]ies by means ( a long piece ( lamp cord1 z %[n1 9 ,figure #dc;a4 ,= #aaj volts use "o lamp1 = #bbj volts use two lamps & = #ddj volts use f\r lamps4 ,atta* "o end ( ! lamp cord to "o side ( ! swit*1 & close ! swit*4 ,take ! o!r end ( ! cord 9 ! h& & press x aga9/ "s "p ( ! weld] frame :]e ! metal is clean & bright4 ,pa9t1 grease & dirt act z insulators & prev5t electrical contact4 ,if ! lamp lights1 ! circuit is 9 electrical contact ) ! frame2 9 o!r words1 gr\nd$4 ,if ! lamps d n light1 connect ! wire to a t]m9al block1 die or slide4 ,if ! lamps !n light1 ! circuit1 coils or leads are 9 electrical contact ) ! l>ge coil 9 ! trans=m] or its connections4 ,if1 h[ev]1 ! lamps d n light 9 ei!r case1 ! lamp cord %\ld be disconnect$ f ! swit* & connect$ to ! o!r side1 & ! op]ations ( connect+ to weld] frame1 dies1 t]m9al blocks1 etc41 z expla9$ above1 %\ld be repeat$4 ,if ! lamps light at any ( ^! connections1 a gr\nd is indicat$4 ,gr\nds c usually be f\nd by c>efully trac+ ! prim>y circuit until a place is f\nd :]e ! insulation is defective4 ,re9sulate & make ! above te/s aga9 to make sure ev]y?+ is cle>4 ,if ! gr\nd c n be locat$ by obs]vation1 ! v>i\s p>ts ( ! prim>y circuit %\ld be disconnect$1 & ! trans=m]1 swit*1 regulator1 etc41 te/$ sep>ately4 ,to locate a gr\nd 9 ! regulator or o!r "p1 disconnect ! l9es runn+ to ! weld] f ! swit*4 ,! te/ lamps us$ 9 ! previ\s te/s are connect$1 "o end ( lamp cord to ! swit*1 ! o!r end to a b9d+ po/ ( ! regulator4 ,connect ! o!r side ( ! swit* to "s "p ( ! regulator h\s+4 7,?is mu/ be a clean connection to a bolt head or ! pa9t %\ld be scrap$ (f47 ,close ! swit*4 ,if ! lamps light1 ! regulator w9d+ or "s "p ( ! swit* is gr\nd$ to ! iron base or core ( ! regulator4 ,if ! lamps d n light1 ?is "p ( ! app>atus is cle>4 ,?is te/ c be easily appli$ to any "p ( ! weld] outfit by connect+ to ! curr5t c>ry+ "p ( ! app>atus1 & to ! iron base or frame t %\ld n c>ry curr5t4 ,if ! lamps light1 x indicates t ! insulation is brok5 d[n or is defective4 ,an ,a4,c4 voltmet] c1 ( c\rse1 be sub/itut$ = ! lamps1 or a ,d4,c4 voltmet] ) ,d4,c4 curr5t c be us$ 9 mak+ ! te/s4 ,a %ort circuit 9 ! prim>y is caus$ by ! insulation ( ! coils becom+ defective & all[+ ! b>e copp] wires to t\* ea* o!r4 ,?is may result 9 a burn out ( "o or m ( ! trans=m] coils1 if ! tr\ble is 9 ! trans=m]1 or 9 ! cont9u$ bl[+ ( fuses 9 ! l9e4 ,feel ( ea* coil sep>ately4 ,if a %ort circuit exi/s 9 a coil x w heat excessively4 ,exam9e all ! wires2 ! insulation may h worn ?r\gh & two ( !m may cross1 or be 9 contact ) ! frame or o!r "p ( ! weld]4 ,a %ort circuit 9 ! regulator w9d+ is indicat$ by failure ( ! app>atus to regulate prop]ly1 & sometimes1 ?\gh n always1 by ! heat+ ( ! regulator coils4 ,! rem$y = a %ort circuit is to re9sulate ! defective p>ts4 ,x is a good plan to prev5t tr\ble by exam9+ ! wir+ occasionally & see t ! insulation is p]fect4 ,to ,locate ,gr\nds & ,%ort ,circuits 9 ! ,second>y1 or ,l[ ,voltage ,side4--,tr\ble ( ?is k9d is indicat$ by ! ma*9e act+ sluggi% or1 p]haps1 refus+ to op]ate4 ,to make a te/1 x w be necess>y to fir/ asc]ta9 ! excit+ curr5t ( y\r p>ticul> trans=m]4 ,?is is ! curr5t ! trans=m] draws on op5 circuit1 or :5 suppli$ ) curr5t f ! l9e ) no /ock 9 ! weld] dies4 ,! foll[+ table w give ?is in=mation close en\gh = all practical purposes3 ,k4,w4 ----------------- ,amp]es at ---------------- ,rat+ #aaj ,volts #bbj ,volts #ddj ,volts #eej ,volts #c #a4e 4#ge 4#ch 4#c #e #b4e #a4be 4#fc 4#e #h #c4f #a4h 4#i 4#gb #aj #d4be #b4ac #a4jg 4#he #ae #f4 #c4 #a4e #a4b #bj #g4 #c4e #a4ge #a4d #cj #i4 #d4e #b4be #a4h #ce #i4f #d4h #b4d #a4ib #ej #aj4 #e4 #b4e #b ,remove ! fuses f ! wall swit* & sub/itute fuses j l>ge en\gh to c>ry ! excit+ curr5t4 ,if no suitable fuses are at h&1 f9e /r&s ( copp] f an ord9>y lamp cord may be us$4 ,^! /r&s are usually ,no4 #cj gauge wire & w fuse at ab\t #aj amp]es4 ,"o or m /r&s %\ld be us$1 dep5d+ on ! am\nt ( excit+ curr5t1 & are connect$ across ! fuse clips 9 place ( fuse wire4 ,place a piece ( wood or fibre betwe5 ! weld+ dies 9 ! weld] z ?\gh y 7 go+ to weld !m4 ,see t ! regulator is on ! highe/ po9t & close ! weld] swit*4 ,if ! second>y circuit is badly gr\nd$1 curr5t w fl[ ?r\gh ! gr\nd1 & ! small fuses or small /r&s ( wire w burn out4 ,?is is an indication t bo? sides ( ! second>y circuit are gr\nd$ or t a %ort circuit exi/s 9 a prim>y coil4 ,9 ei!r case ! weld] %\ld n be op]at$ until ! tr\ble is f\nd & remov$4 ,if1 h[ev]1 ! small fuses d n bl[1 remove same & replace ! l>ge fuses1 !n disconnect wires runn+ f ! wall swit* to ! weld] & sub/itute two pieces ( ,no4 #h or ,no4 #f insulat$ copp] wire1 aft] scrap+ (f ! insulation = an in* or two at ea* end4 ,connect "o wire f ! swit* to ! frame ( weld]2 ?is w leave "o loose end4 ,hold ?is a foot or s away f ! place :]e ! insulation is cut (f2 !n turn on ! curr5t & /rike ! free end ( ?is wire lightly aga9/ "o ( ! copp] dies1 draw+ x away quickly4 ,if no sp>k+ is produc$1 ! second>y circuit is free f gr\nd1 & y w !n look = a brok5 connection 9 ! circuit4 ,"s caution mu/ be us$ 9 mak+ ! above te/1 z 9 case "o t]m9al is heavily gr\nd$ ! te/+ wire may be fus$ if all[$ to /ay 9 contact ) ! die4 ,! ,rem$y4--,clean ! slides1 dies & t]m9al blocks ?or\ghly & dry out ! fibre insulation if x is damp4 ,see t no scale or metal has work$ "u ! slid+ p>ts1 & t ! second>y leads d n t\* ! frame4 ,if ! gr\nd is v heavy x may be necess>y to remove ! slides 9 ord] to facilitate ! exam9ation & removal ( ! gr\nd4 ,insulation1 :]e torn or worn ?r\gh1 mu/ be c>efully replac$ or tap$4 ,if ! trans=m] coils are gr\nd$ to ! iron core ( ! trans=m] or to ! second>y1 x may be necess>y to remove ! coils & re9sulate !m at ! po9ts ( contact4 ,a %ort circuit$ coil w heat excessively & ev5tually burn out4 ,?is may mean a new coil if y are unable to repair ! old "o4 ,9 all cases ! trans=m] w9d+s %\ld be protect$ f me*anical injury or dampness4 ,unless excessively ov]load$1 trans=m]s w la/ = ye>s )\t giv+ a mom5t's tr\ble1 if !y are n expos$ to moi/ure or are n injur$ me*anically4 ,! mo/ common tr\ble arises f poor electrical contacts1 & !y are ! cause ( endless tr\ble & annoyance4 ,see t all connections are clean & bright4 ,take out ! dies e day or two & see t !re is no scale1 grease or dirt betwe5 !m & ! hold]s4 ,clean !m ?or\ghly be=e replac+4 ,tight5 ! bolts runn+ f ! trans=m] leads to ! "w jaws4 ,,electric ,,arc ,,weld+ ,?is me?od be>s no relation to ! "o j consid]$1 except t ! s\rce ( heat is ! same 9 bo? cases4 ,arc weld+ makes use ( ! flame produc$ by ! voltaic arc 9 practically ! same way t oxy-acetyl5e weld+ uses ! flame f ! gases4 ,if ! ends ( two pieces ( c>bon ?r\gh :i* a curr5t ( electricity is fl[+ :ile !y are 9 contact are sep>at$ f ea* o!r q sl[ly1 a brilliant arc ( flame is =m$ betwe5 !m :i* consi/s ma9ly ( c>bon vapor4 ,! c>bons are consum$ by comb9ation ) ! oxyg5 9 ! air & ?r\gh be+ turn$ to a gas "u ! int5se heat4 ,! mo/ int5se action takes place at ! c5t] ( ! c>bon :i* c>ries ! positive curr5t & ?is is ! po9t ( greate/ heat4 ,! temp]ature at ?is po9t 9 ! arc is great] ?an c be produc$ by any o!r means "u human control4 ,an arc may be =m$ betwe5 pieces ( metal1 call$ electrodes1 9 ! same way z betwe5 c>bon4 ,! metallic arc is call$ a flam+ arc & z ! metal ( ! electrode burns ) ! heat1 x gives ! flame a color *>act]i/ic ( ! mat]ial be+ us$4 ,! metallic arc may be drawn out to a mu* great] l5g? ?an "o =m$ betwe5 c>bon electrodes4 ,arc ,weld+ is c>ri$ out by draw+ a piece ( c>bon :i* is ( negative pol>ity away f ! pieces ( metal to be weld$ :ile ! metal is made positive 9 pol>ity4 ,! negative wire is fa/5$ to ! c>bon electrode & ! "w is laid on a table made ( ca/ or wr\ght iron to :i* ! positive wire is made fa/4 ,! direction ( ! flame is !n f ! metal be+ weld$ to ! c>bon & ! "w is ?us prev5t$ f be+ saturat$ ) c>bon1 :i* w\ld prove v detrim5tal to its /r5g?4 ,a second>y advantage is f\nd 9 ! fact t ! greate/ heat is at ! metal be+ weld$ because ( its be+ ! positive electrode4 ,! c>bon electrode is usually made f "o qu>t] to "o & a half in*es 9 diamet] & f six to twelve in*es 9 l5g?4 ,! l5g? ( ! arc may be any:]e f "o in* to f\r in*es1 dep5d+ on ! size ( ! "w be+ h&l$4 ,:ile ! p>ts are c>efully insulat$ to avoid dang] ( %ock1 x is necess>y = ! op]ator to we> rubb] gloves z a fur!r protection1 & to we> "s =m ( hood ov] ! head to %ield him aga9/ ! extreme heat lib]at$4 ,?is hood may be made f metal1 al?\gh "s mat]ial t does n conduct electricity is to be pref]r$4 ,! "w is wat*$ ?r\gh pieces ( glass =m$ ) "o %eet1 :i* is ei!r blue or gre51 plac$ ov] ano!r :i* is r$4 ,scre5s ( glass are sometimes us$ )\t ! head protector4 ,"s protection = ! eyes is absolutely necess>y because ( ! int5se :ite light4 ,x is seldom necess>y to preheat ! "w z ) ! gas processes1 because ! heat is localiz$ at ! po9t ( weld+ & ! action is s rapid t ! expansion is n s great4 ,! necessity ( preheat+1 h[ev]1 dep5ds entirely on ! mat]ial1 =m & size ( ! "w be+ h&l$4 ,! same advice applies to arc weld+ z to ! gas flame me?od b 9 a less] degree4 ,fill+ rods are us$ 9 ! same way z ) any o!r flame process4 ,x is ! purpose ( ?is explanation to /ate ! fundam5tal pr9ciples ( ! application ( ! electric arc to weld+ metals1 & by apply+ ! pr9ciples ! foll[+ que/ions w be answ]$3 ,:at metals c be weld$ by ! electric arc8 ,:at difficulties are to be enc\nt]$ 9 apply+ ! electric arc to weld+8 ,:at is ! /r5g? ( ! weld 9 comp>ison ) ! orig9al piece8 ,:at is ! function ( ! arc weld+ ma*9e itself8 ,:at is ! comp>ative application ( ! electric arc & ! oxy-acetyl5e me?od & o!rs ( a simil> nature8 ,! answ]s to ^! que/ions w make x possible to und]/& ! application ( ?is process to any "w4 ,9 a great _m places ! use ( ! arc is cutt+ ! co/ ( weld+ to a v small fraction ( :at x w\ld be by any o!r me?od1 s t ! importance ( ?is me?od may be well und]/ood4 ,any two metals :i* are br\ght to ! melt+ temp]ature & appli$ to ea* o!r w adh]e s t !y are no m apt to break at ! weld ?an at any o!r po9t outside ( ! weld4 ,x is ! prop]ty ( all metals to /ick toge!r "u ^! conditions4 ,! electric arc is us$ 9 ?is connection m]ely z a heat+ ag5t4 ,?is is its only function 9 ! process4 ,x has advantages 9 its ease ( application & ! *eapness ) :i* heat c be lib]at$ at any giv5 po9t by its use4 ,!re is no?+ 9 connection ) arc weld+ t ! above pr9ciples w n answ]2 t is1 t metals at ! melt+ po9t w weld & t ! electric arc w furni% ! heat to br+ !m to ?is po9t4 ,z to ! fir/ "q1 :at metals c be weld$1 all metals c be weld$4 ,! difficulties :i* are enc\nt]$ are z foll[s3 ,9 ! case ( brass or z9c1 ! metals w be cov]$ ) a coat ( z9c oxide be=e !y rea* a weld+ heat4 ,?is z9c oxide makes x impossible = two clean surfaces to come toge!r & "s me?od has to be us$ = elim9at+ ?is possibility & all[+ ! two surfaces to jo9 )\t ! possibility ( ! oxide int]v5+4 ,! same is true ( alum9um1 9 :i* ! oxide1 alum9a1 w be =m$1 & ) sev]al o!r alloys compris+ elem5ts ( diff]5t melt+ po9ts4 ,9 ord] to elim9ate ^! oxides1 x is necess>y 9 practical "w1 to puddle ! weld2 ?is is1 to h a suffici5t quantity ( molt5 metal at ! weld s t ! oxide is float$ away4 ,:5 ?is is done1 ! two surfaces :i* are to be jo9$ are cov]$ ) a coat ( melt$ metal on :i* floats ! oxide & o!r impurities4 ,! two pieces are ?us all[$ to jo9 :ile _! surfaces are protect$4 ,?is precaution is n necess>y 9 work+ ) /eel except 9 extreme cases4 ,ano!r difficulty :i* is met ) 9 ! weld+ ( a great _m metals is _! expansion "u heat1 :i* results 9 s great a contraction :5 ! weld cools t ! metal is left ) a consid]able /ra9 on x4 ,9 extreme cases ?is w result 9 crack+ at ! weld or ne> x4 ,to elim9ate ?is dang] x is necess>y to apply heat ei!r all ov] ! piece to be weld$ or at c]ta9 po9ts4 ,9 ! case ( ca/ iron & sometimes ) copp] x is necess>y to anneal aft] weld+1 s9ce o!rwise ! weld$ pieces w be v brittle on acc\nt ( ! *ill+4 ,?is is also true ( malleable iron4 ,v ?9 metals :i* are weld$ toge!r & are n back$ up by some?+ to c>ry away ! excess heat1 are v apt to burn ?r\gh1 leav+ a hole :]e ! weld %\ld be4 ,?is difficulty c be elim9at$ by back+ up ! weld ) a metal face or by decreas+ ! int5sity ( ! arc s t ?is melt+ ?r\gh w n occur4 ,h[ev]1 ! practical limit = arc weld+ )\t back+ up ! "w ) a metal face or decreas+ ! int5sity ( ! arc is approximately #bb gauge1 al?\gh ?9n] metal c be weld$ by a v skillful & c>eful op]ator4 ,"o difficulty ) arc weld+ is ! lack ( skillful op]ators4 ,?is me?od is (t5 look$ ^u z be+ some?+ out ( ! ord9>y & gov]n$ by laws entirely diff]5t f o!r weld+4 ,z a matt] ( fact1 x does n take z mu* skill to make a good arc weld z x does to make a good weld 9 a =ge fire z ! blacksmi? does x4 ,!re are few jobs :i* _c be h&l$ successfully by an op]ator ( av]age intellig5ce ) "o week's in/ructions1 al?\gh 8 "w w become bett] & bett] 9 quality z he cont9ues to use ! arc4 ,n[ comes ! "q ( ! /r5g? ( ! weld aft] x has be5 made4 ,?is /r5g? is equally z great z t ( ! metal t is us$ to make ! weld4 ,x %\ld be rememb]$1 h[ev]1 t ! metal :i* goes into ! weld is put 9 !re z a ca/+ & has n be5 roll$4 ,?is w\ld make ! /r5g? ( ! weld z great z ! same metal t is us$ = fill+ if 9 ! ca/ =m4 ,two pieces ( /eel c\ld be weld$ toge!r hav+ a t5sile /r5g? at ! weld ( #ej1jjj p\nds4 ,high] /r5g?s ?an ?is c be obta9$ by ! use ( special alloys = ! fill+ mat]ial or by roll+4 ,welds ) a t5sile /r5g? z great z m5tion$ w give a result :i* is p]fectly satisfactory 9 almo/ all cases4 ,!re are a great _m jobs :]e x is possible to fill up ! weld1 t is1 make ! section at ! po9t ( ! weld a little l>g] ?an ! section ?r\gh ! re/ ( ! piece4 ,by do+ ?is1 ! disadvantages ( ! weld be+ 9 ! =m ( a ca/+ 9 comp>ison ) ! re/ ( ! piece be+ 9 ! =m ( roll$ /eel c be ov]come1 & make ! weld itself ev5 /rong] ?an ! orig9al piece4 ,! next "q is ! adaptability ( ! electric arc 9 comp>ison ) =ge fire1 oxy-acetyl5e or o!r me?od4 ,! answ] is some:at difficult if made g5]al4 ,!re are no d\bt "s cases :]e ! use ( a drop hamm] & =ge fire or ! use ( ! oxy-acetyl5e tor* w make1 all ?+s be+ consid]$1 a bett] job ?an ! use ( ! electric arc1 al?\gh a case :]e ?is is absolutely prov$ is r>e4 ,! electric arc w melt metal 9 a weld = less ?an ! same metal c be melt$ by ! use ( ! oxy-acetyl5e tor*1 &1 on acc\nt ( ! fact t ! heat c be appli$ exactly :]e x is requir$ & 9 ! am\nt requir$1 ! arc c 9 almo/ all cases supply weld+ heat = less co/ ?an a =ge fire or heat+ furnace4 ,! "o great advantage ( ! oxy-acetyl5e me?od 9 comp>ison ) o!r me?ods ( weld+ is ! fact t 9 "s cases ( v ?9 %eet1 ! weld c be made some:at soon] ?an is possible o!rwise4 ,) metal ( #ah gauge or ?ick]1 ?is advantage is elim9at$4 ,9 cutt+ /eel1 ! oxy-acetyl5e tor* is sup]ior to almo/ any o!r possible me?od4 ,arc ,weld+ ,ma*9es4--,a consid]ation ( ! function & purpose ( ! v>i\s types ( arc weld+ ma*9es %[s t ! only reason = ! use ( any ma*9e is ei!r = conv]sion ( ! curr5t f alt]nat+ to direct1 or1 if ! curr5t is already direct1 !n ! sav+ 9 ! application ( ?is curr5t 9 ! arc4 ,x is practically out ( ! "q to apply an alt]nat+ curr5t arc to weld+ = ! reason t 9 any arc practically all ! heat is lib]at$ at ! positive electrode1 :i* means t1 9 alt]nat+ curr5t1 half ! heat is lib]at$ at ea* electrode z ! curr5t *anges its direction ( fl[ or alt]nates4 ,ano!r disadvantage ( ! alt]nat+ arc is t x is difficult ( control & application4 ,9 all arc weld+ by ! use ( ! c>bon arc1 ! positive electrode is made ! piece to be weld$1 :ile 9 weld+ ) metallic electrodes ?is may be ei!r ! piece to be weld$ ( ! rod t is us$ z a fill]4 ,! voltage across ! arc is a v>iable quantity1 dep5d+ on ! l5g? ( ! flame1 its temp]ature & ! gases lib]at$ 9 ! arc4 ,) a c>bon electrode ! voltage w v>y f z]o to =ty-five volts4 ,) ! metallic electrode ! voltage w v>y f z]o to ?irty volts4 ,x is1 !re=e1 necess>y = ! weld+ ma*9e to be able to furni% to ! arc ! requisite am\nt ( curr5t1 ?is am\nt be+ v>i$1 & furni% x at all times at ! voltage requir$4 ,! simple/ weld+ app>atus is a resi/ance 9 s]ies ) ! arc4 ,?is is entirely satisfactory 9 e way except 9 co/ ( curr5t4 ,by ! use ( resi/ance 9 s]ies ) ! arc & us+ #bbj volts z ! supply1 f eighty to n9ety p] c5t ( ! curr5t is lo/ 9 heat at ! resi/ance4 ,ano!r disadvantage is ! fact t mo/ mat]ials *ange _! resi/ance z _! temp]ature *anges1 ?us mak+ ! am\nt ( curr5t = ! arc a v>iable quantity1 dep5d+ on ! temp]ature ( ! resi/ance4 ,!re h be5 v>i\s me?ods orig9at$ = sav+ ! p[] m5tion$ & a good _m ma*9es h be5 put on ! m>ket = ?is purpose4 ,all ( !m save "s p[] ov] :at a pla9 resi/ance w\ld use4 ,practically all arc weld+ ma*9es at ! pres5t "t are motor g5]ator sets1 ! motor ( :i* is arrang$ = ! supply voltage & curr5t1 ?is motor be+ direct connect$ to a comp\nd w\nd g5]ator deliv]+ approximately sev5ty-five volts direct curr5t4 ,!n by ! use ( a resi/ance1 ?is sev5ty-five volt supply is appli$ to ! arc4 ,s9ce ! voltage across ! arc w v>y f z]o to fifty volts1 ?is ma*9e w save f z]o up to sev5ty p] c5t ( ! p[] t ! ma*9e deliv]s4 ,! re/ ( ! p[]1 ( c\rse1 has to be dissipat$ 9 ! resi/ance us$ 9 s]ies ) ! arc4 ,a motor g5]ator set :i* c be pur*as$ f any electrical company1 ) a long piece ( f5ce wire w\nd ar\nd a piece ( asbe/os1 gives results equally z good & at a v small "p ( ! fir/ co/4 ,x is possible to con/ruct a ma*9e :i* w elim9ate all losses 9 ! resi/ance2 9 o!r words1 elim9ate all resi/ance 9 s]ies ) ! arc4 ,a ma*9e ( ?is k9d w save its co/ )9 a v %ort "t1 provid+ ! weld] is us$ to any ext5t4 ,putt+ x 9 figures1 ! results are z foll[s = av]age conditions4 ,curr5t at #b;c p] kil[att h\r1 metallic electrode arc ( #aej amp]es1 c>bon arc #ejj amp]es2 voltage across ! metallic electrode arc #bj1 voltage across ! c>bon arc #ce4 ,supply curr5t #bbj volts1 direct4 ,9 ! case ( ! metallic electrode1 if resi/ance is us$1 ! co/ ( runn+ ?is arc is sixty-six c5ts p] h\r4 ,) ! c>bon electrode1 #b4bj p] h\r4 ,if a motor g5]ator set ) a sev5ty volt con/ant pot5tial ma*9e is us$ = a weld]1 ! co/ w be z foll[s3 ,metallic electrode #be4b;c4 ,c>bon electrode #hd;c p] h\r4 ,) a ma*9e :i* w deliv] ! requir$ voltage at ! arc & elim9ate all ! resi/ance 9 s]ies ) ! arc1 ! co/ w be z foll[s3 ,metallic electrode #g4b;c p] h\r2 c>bon electrode #db;c p] h\r4 ,?is is ) ! und]/&+ t ! arc is held con/ant & cont9u\sly at its full value4 ,?is1 h[ev]1 is practically impossible & ! actual load factor is approximately fifty p] c5t1 :i* w\ld mean t op]at+ a weld] z x is usually op]at$1 ?is result w be r$uc$ to "o-half ( t /at$ 9 all cases4 ,,*apt] ,,vii ,,h& ,,=g+ ,,& ,,weld+ ,smi?+1 or blacksmi?+1 is ! process ( work+ heat$ iron1 /eel or o!r metals by =g+1 b5d+ or weld+ !m4 ,! ,=ge4--,! metal is heat$ 9 a =ge consi/+ ( a %all[ pan = hold+ ! fire1 9 ! c5t] ( :i* is an op5+ f bel[ ?r\gh :i* air is =c$ to make a hot fire4 ,illu/ration3 ,figure #dh4--,tuy]e ,con/ruction on a ,=ge ,air is =c$ ?r\gh ?is hole1 call$ a tuy]e 7,figure #dh7 by means ( a h& bell[s1 a rot>y fan op]at$ ) crank or lev]1 or ) a fan driv5 f an electric motor4 ,! h>d] ! air is driv5 into ! fire above ! tuy]e ! m oxyg5 is furni%$ & ! hott] ! fire becomes4 ,directly bel[ ! tuy]e is an op5+ ?r\gh :i* ! a%es t drop f ! fire may be clean$ out4 ,! ,fire4--,! fire is made by plac+ a small piece ( wa/e soak$ 9 oil1 k]os5e or gasol9e1 ov] ! tuy]e1 light+ ! wa/e1 !n />t+ ! fan or bl[] sl[ly4 ,gradually cov] ! wa/e1 :ile x is burn+ brightly1 ) a lay] ( s(t coal4 ,! coal w cat* fire & burn aft] ! wa/e has be5 consum$4 ,a piece ( wa/e half ! size ( a p]son's h& is ample = ?is purpose4 ,! fuel %\ld be smi?+ coal4 ,a lump ( smi?+ coal breaks easily1 %[s clean & ev5 on all sides & %\ld n break into lay]s4 ,! coal is brok5 into f9e pieces & wet be=e be+ us$ on ! fire4 ,! fire %\ld be kept deep en\gh s t !re is always ?ree or f\r in*es ( fire bel[ ! piece ( metal to be heat$ & !re %\ld be en\gh fire above ! "w s t no "p ( ! metal be+ heat$ comes 9 contact ) ! air4 ,! fire %\ld be kept z small z possible :ile foll[+ ^! rules z to dep?4 ,to make ! fire l>g]1 loos5 ! coal ar\nd ! edges4 ,to make ! fire small]1 pack wet coal ar\nd ! edges 9 a compact mass & loos5 ! fire 9 ! c5t]4 ,add fre% coal only ar\nd ! edges ( ! fire4 ,x w turn to coke & c !n be rak$ onto ! fire4 ,bl[ only en\gh air into ! fire to keep x burn+ brightly1 n s mu* t ! fire is bl[n up ?r\gh ! top ( ! coal pack4 ,to prev5t ! fire f go+ out betwe5 jobs1 /ick a piece ( s(t wood into x & cov] ) fre% wet coal4 ,tools4--,! hamm] is a ball p5e1 or blacksmi?'s hamm]1 weigh+ ab\t a p\nd & a half4 ,! sl$ge is a heavy hamm]1 weigh+ f #e to #bj p\nds & hav+ a h&le #cj to #cf in*es long4 ,! anvil is a heavy piece ( wr\ght iron 7,figure #di71 fac$ ) /eel & hav+ f\r legs4 ,x has a po9t$ horn on "o end1 an ov]hang+ tail on ! o!r end & a flat top4 ,9 ! tail !re is a squ>e hole call$ ! h>die hole & a r\nd "o call$ ! spud hole4 ,illu/ration3 ,figure #di4--;,anvil1 ,%[+ ,horn1 ,tail1 ,h>die ,hole & ,spud ,hole ,tongs1 ) h&les ab\t "o foot long & jaws suitable = hold+ ! "w1 are us$4 ,to secure a firm grip on ! "w1 ! jaws may be heat$ r$ hot & hamm]$ into %ape ov] ! piece to be held1 ?us giv+ a prop]ly =m$ jaw4 ,jaws %\ld t\* ! "w along _! entire l5g?4 ,! set hamm] is a hamm]1 "o end ( ^: head is squ>e & flat1 & f ?is face ! head tap]s ev5ly to ! o!r face4 ,! l>ge face is ab\t #a-a_/d in*es squ>e4 ,! flatt] is a hamm] hav+ "o face ( its head flat & ab\t #b-a_/b in*es squ>e4 ,swages are hamm]s hav+ specially =m$ faces = f9i%+ r\nds1 squ>es1 hexagons1 ovals1 tap]s1 etc4 ,full]s are hamm]s hav+ a r\nd$ face1 long 9 "o direction4 ,!y are us$ = spread+ metal 9 "o direction only4 ,! h>dy is a =m ( *isel ) a %ort1 squ>e %ank :i* may be set into ! h>die hole = cutt+ (f hot b>s4 ,op]ations4--,blacksmi?+ consi/s ( b5d+1 draw+ or upsett+ ) ! v>i\s hamm]s1 or 9 pun*+ holes4 ,b5d+ is done ov] ! squ>e corn]s ( ! anvil if squ>e corn]$ b5ds are desir$1 or ov] ! horn ( ! anvil if r\nd+ b5ds1 eyes1 hooks1 etc41 are want$4 ,to b5d a r+ or eye 9 ! end ( a b>1 fir/ figure ! l5g? ( /ock ne$$ by multiply+ ! diamet] ( ! hole by #ca_/g1 !n heat ! piece to a good full r$ at a po9t ?is di/ance back f ! end4 ,next b5d ! iron ov] at a #ij degree angle 7squ>e7 at ?is po9t4 ,next1 heat ! iron f ! b5d j made cle> to ! po9t & make ! eye by lay+ ! "p t 0 b5t squ>e ov] ! horn ( ! anvil & b5d+ ! extreme tip into "p ( a circle4 ,keep pu%+ ! piece f>!r & f>!r ov] ! horn ( ! anvil1 b5d+ x z y g4 ,d n hamm] directly ov] ! horn ( ! anvil1 b on ! side :]e y are do+ ! b5d+4 ,to make ! outside ( a b5d squ>e1 %>p & full1 r ?an slightly r\nd+1 ! b5t piece mu/ be laid edgewise on ! face ( ! anvil4 ,t is1 aft] mak+ ! b5d ov] ! corn] ( ! anvil1 lay ! piece on top ( ! anvil s t its edge & n ! flat side re/s on ! anvil top4 ,) ! "w 9 ?is position1 /rike directly aga9/ ! corn] ) ! hamm] s t ! bl[s come 9 l9e1 fir/ ) "o leg ( ! "w1 !n ! o!r1 & always directly on ! corn] ( ! piece4 ,?is op]ation _c be p]=m$ by lay+ ! "w s t "o leg hangs ov] ! anvil's corn]4 ,to make a %\ld] on a rod or b>1 heat ! "w & lay flat across ! top ( ! anvil ) ! po9t at :i* ! %\ld] is desir$ at ! edge ( ! anvil4 ,!n place ! set hamm] on top ( ! piece1 ) ! outside edge ( ! set hamm] directly ov] ! edge ( ! anvil4 ,:ile hamm]+ 9 ?is position keep ! "w turn+ cont9ually4 ,to draw /ock means to make x long] & ?9n] by hamm]+4 ,a piece to be drawn out is usually laid across ! horn ( ! anvil :ile be+ /ruck ) ! hamm]4 ,! metal is !n spread 9 only "o direction 9 place ( be+ spread 9 e direction1 z x w\ld be if laid on ! anvil face4 ,to draw ! "w1 heat x to z high a temp]ature z x w /& )\t ?r[+ sp>ks & burn+4 ,! full] may be us$ = draw+ metal 9 place ( lay+ ! "w ov] ! horn ( ! anvil4 ,:5 draw+ r\nd /ock1 x %\ld be fir/ drawn out squ>e1 & :5 almo/ d[n to size x may be r\nd$4 ,:5 po9t+ /ock1 ! same rule ( fir/ draw+ out squ>e applies4 ,upsett+ means to make a piece %ort] 9 l5g? & great] 9 ?ickness or wid?1 or bo? %ort] & ?ick]4 ,to upset %ort pieces1 heat to a bright r$ at ! place to be upset1 !n /& on end on ! anvil face & hamm] directly d[n on top until ( ! "r =m4 ,long] pieces may be swung aga9/ ! anvil or plac$ upright on a heavy piece ( metal ly+ on ! floor or t is sunk into ! floor4 ,:ile /&+ on ?is heavy piece ! metal may be upset by /rik+ d[n on ! end ) a heavy hamm] or ! sl$ge4 ,if a b5d appe>s :ile upsett+1 x %\ld be /raight5$ by hamm]+ back into %ape on ! anvil face4 ,light bl[s affect ! metal = only a %ort di/ance f ! po9t ( /rik+1 b heavy bl[s t5d to swell ! metal m equally ?r\gh its entire l5g?4 ,9 driv+ rivets t %\ld fill ! holes1 heavy bl[s %\ld be /ruck1 b to %ape ! end ( a rivet or to make a head on a rod1 light bl[s %\ld be us$4 ,! "p ( ! piece t is heat$ mo/ w upset ! mo/4 ,to pun* a hole ?r\gh metal1 use a tool /eel pun* ) its end slightly tap]+ to a size a little small] ?an ! hole to be pun*$4 ,! end ( ! pun* mu/ be squ>e across & nev] po9t$ or r\nd$4 ,fir/ drive ! pun* "p way ?r\gh f "o side & !n turn ! "w ov]4 ,:5 y turn x ov]1 notice :]e ! bulge appe>s & 9 t way locate ! hole & drive ! pun* ?r\gh f ! second side4 ,?is makes a clean] & m ev5 hole ?an to drive completely ?r\gh f "o side4 ,:5 ! pun* is driv5 9 f ! second side1 ! place to be pun*$ ?r\gh %\ld be laid ov] ! spud hole 9 ! tail ( ! anvil & ! piece driv5 out ( ! "w4 ,"w :5 hot is l>g] ?an x w be aft] cool+4 ,?is mu/ be rememb]$ :5 fitt+ p>ts or tr\ble w result4 ,a two-foot b> ( /eel w be #a_/d in* long] :5 r$ hot ?an :5 cold4 ,! temp]atures ( iron correspond to ! foll[+ colors3 ,dulle/ r$ se5 9 ! d>k444 #hgh ,dulle/ r$ se5 9 daylight444 #hhg ,dull r$44444444444444444444444 #aajj ,full r$44444444444444444444444 #acgj ,light r$4444444444444444444444 #aeej ,orange4444444444444444444444444 #afej ,light orange4444444444444444444 #agbe ,yell[4444444444444444444444444 #ahbe ,light yell[4444444444444444444 #aiej ,b5d+ ,pipes & ,tubes4--,x is difficult to make b5ds or curves 9 pipes & tub+ )\t leav+ a noticeable bulge at "s po9t ( ! "w4 ,seamless /eel tub+ may be h&l$ )\t v great dang] ( ?is tr\ble if c>e is us$1 b iron pipe1 hav+ a seam runn+ l5g?wise1 mu/ be giv5 special att5tion to avoid op5+ ! seam4 ,b5ds may be made )\t k9k+ if ! tube or pipe is br\ght to a full r$ heat all ! way ar\nd its circumf]5ce & at ! place :]e ! b5d is desir$4 ,hold ! cool portion solidly 9 a vise &1 by tak+ hold ( ! free end1 b5d v sl[ly & ) a /eady pull4 ,! pipe mu/ be kept at full r$ heat ) ! flames f "o or m tor*es & mu/ n be hamm]$ to produce ! b5d4 ,if a suffici5t pur*ase _c be secur$ on ! free end by ! h&1 ins]t a piece ( rod or a small] pipe into ! op5+4 ,:ile mak+ ! b5d1 %\ld small bulges appe>1 !y may be hamm]$ back into %ape be=e proce$+ ) ! "w4 ,tub+ or pipes may be b5t :ile be+ held betwe5 two flat metal surfaces :ile at a bright r$ heat4 ,! metal plates at ea* side ( ! "w prev5t bulg+4 ,ano!r me?od by :i* tub+ may be b5t consi/s ( fill+ completely ) tightly pack$ s& & fitt+ a solid cap or plug at ea* end4 ,?9 brass tub+ may be fill$ ) melt$ res9 & may be b5t aft] ! res9 cools4 ,to remove ! res9 x is necess>y to heat ! tube1 all[+ x to run out4 ,l>ge jobs ( b5d+ %\ld be h&l$ 9 special pipe b5d+ ma*9es 9 :i* ! "w is =c$ ?r\gh =m$ rolls :i* prev5t its bulg+4 ,,weld+ ,weld+ ) ! heat ( a blacksmi? =ge fire1 or a coal or illum9at+ gas fire1 c only be p]=m$ ) iron & /eel because ( ! l[ heat :i* is n localiz$ z ) ! oxy-acetyl5e & electric processes4 ,iron to be weld$ 9 ?is mann] is heat$ until x rea*es ! temp]ature indicat$ by an orange color1 n :ite1 z is (t5 /at$1 ?is orange color be+ slightly above #cfjj degrees ,fahr5heit4 ,/eel is usually weld$ at a bright r$ heat because ( ! dang] ( oxidiz+ or burn+ ! metal if ! temp]ature is c>ri$ above ?is po9t4 ,! ,fire4--,if made 9 a =ge1 ! fire %\ld be built f good smi?+ coal or1 bett] /ill1 f coke4 ,gas fires are1 ( c\rse1 produc$ by suitable burn]s & require no special prep>ation except adju/m5t ( ! heat to ! prop] degree = ! size & ?ickness ( ! metal be+ weld$ s t x w n be burn$4 ,a coal fire us$ = ord9>y =g+ op]ations %\ld n be us$ = weld+ because ( ! impurities x conta9s4 ,a fre% fire %\ld be built ) a r deep b$ ( coal1 f\r to eight in*es be+ ab\t "r = "w ord9>ily met )4 ,! fire %\ld be kept burn+ until ! coal ar\nd ! edges has be5 ?or\ghly cok$ & a suffici5t quantity ( fuel %\ld be on & ar\nd ! fire s t no fre% coal w h to be add$ :ile work+4 ,aft] ! cok+ process has progress$ suffici5tly1 ! edges %\ld be pack$ d[n & ! fire made z small z possible :ile /ill surr\nd+ ! ends to be jo9$4 ,! fire %\ld n be alt]$ by pok+ x :ile ! metal is be+ heat$4 ,! be/ =m ( fire to use is "o hav+ r high banks ( cok$ coal on ea* side ( ! mass1 leav+ an op5+ or *annel f end to end4 ,?is w all[ ! add$ fuel to be br\ght d[n on top ( ! fire ) a small am\nt ( di/urbance4 ,prep>+ to ,weld4--,if ! op]ator is n famili> ) ! metal to be h&l$1 x is be/ to secure a te/ piece if at all possible & try heat+ x & jo9+ ! ends4 ,v>i\s grades ( iron & /eel call = diff]5t me?ods ( h&l+ & = diff]5t degrees ( heat1 ! prop] me?od & temp]ature be+ det]m9$ be/ by actual te/ "u ! hamm]4 ,! =m ( ! pieces also has a great deal to d ) _! h&l+1 especially 9 ! case ( a m or less inexp]i5c$ workman4 ,if ! pieces are at all irregul> 9 %ape1 ! motions %\ld be gone ?r\gh ) be=e ! metal is heat$ & ! be/ positions on ! anvil z well z 9 ! fire det]m9$ ) reg>d to ! conv5i5ce ( ! workman & spe$ ( h&l+ ! "w aft] be+ br\ght to a weld+ temp]ature4 ,unnatural positions at ! anvil %\ld be avoid$ z good "w is mo/ difficult ( p]=mance "u ^! conditions4 ,sc>f+4--,:ile !re are _m =ms ( welds1 dep5d+ on ! relative %ape ( ! pieces to be jo9$1 ! portions t are to meet & =m "o piece are always %ap$ 9 ! same g5]al way1 ?is %ape be+ call$ a sc>f4 ,! end ( a piece ( "w1 :5 sc>f$1 is tap]$ (f on "o side s t ! extremity comes to a r %>p edge4 ,! o!r side ( ! piece is left flat & a cont9uation 9 ! same /raight plane ) its side ( ! :ole piece ( "w4 ,! end is !n 9 ! =m ( a bevel or mitre jo9t 7,figure #ej74 ,illu/ration3 ,figure #ej4--,sc>f+ ,ends ( ,"w ,ready = ,weld+ ,sc>f+ may be produc$ 9 any "o ( sev]al ways4 ,! usual me?od is to br+ ! ends to a =g+ heat1 at :i* "t !y are upset to give a l>g] body ( metal at ! ends to be jo9$4 ,?is body ( metal is !n hamm]$ d[n to ! tap] on "o side1 ! l5g? ( ! tap]$ portion be+ ab\t "o & a half times ! ?ickness ( ! :ole piece be+ h&l$4 ,ea* piece %\ld be giv5 ?is %ape be=e proce$+ f>!r4 ,! sc>f may be produc$ by fil+1 saw+ or *isel+ ! ends1 al?\gh ?is is n good practice because x is !n impossible to give ! desir$ upset & additional metal = ! weld4 ,?is add$ ?ickness is call$ = by ! fact t ! metal burns away to a c]ta9 ext5t or turns to scale1 :i* is remov$ be=e weld+4 ,:5 ! two ends h be5 giv5 ?is %ape !y %\ld n fit z closely toge!r z might be expect$1 b %\ld t\* only at ! c5t] ( ! area to be jo9$ 7,figure #ea74 ,t is to say1 ! surface ( ! bevel$ portion %\ld bulge 9 ! middle or %\ld be convex 9 %ape s t ! edges are sep>at$ by a little di/ance :5 ! pieces are laid toge!r ) ! bevels t[>d ea* o!r4 ,?is is done s t ! scale :i* is =m$ on ! metal by ! heat ( ! fire c h a *ance to escape f ! int]ior ( ! weld z ! two p>ts are =c$ toge!r4 ,illu/ration3 ,figure #ea4--,prop] ,%ape ( ,sc>f$ ,ends ,if ! sc>f 7 to be =m$ ) "o or m ( ! edges t\*+ ea* o!r at ! same "t or be=e ! c5t]s did s1 ! scale w\ld be imprison$ )9 ! body ( ! weld & w\ld cause ! f9i%$ "w to be weak1 :ile possibly giv+ a satisfactory appe>ance f ! outside4 ,fluxes4--,9 ord] to assi/ 9 remov+ ! scale & o!r impurities & to make ! weld+ surfaces z clean z possible :ile be+ jo9$1 v>i\s flux+ mat]ials are us$ z 9 o!r me?ods ( weld+4 ,= weld+ iron1 a flux ( :ite s& is usually us$1 ?is mat]ial be+ plac$ on ! metal aft] x has be5 br\ght to a r$ heat 9 ! fire4 ,/eel is weld$ ) dry borax p[d]1 ?is flux be+ appli$ at ! same "t z ! iron flux j m5tion$4 ,borax may also be us$ = iron weld+ & a mixture ( borax ) /eel bor+s may also be us$ = ei!r class ( "w4 ,mixtures ( sal ammoniac ) borax h be5 successfully us$1 ! proportions be+ ab\t f\r p>ts ( borax to "o ( sal ammoniac4 ,v>i\s prep>$ flux+ p[d]s are on ! m>ket = ?is "w1 practically all ( !m produc+ satisfactory results4 ,aft] ! metal has be5 9 ! fire long en\gh to rea* a r$ heat1 x is remov$ tempor>ily &1 if small en\gh 9 size1 ! ends are dipp$ into a box ( flux4 ,if ! pieces are l>ge1 !y may simply be pull$ to ! edge ( ! fire & ! flux !n spr9kl$ on ! portions to be jo9$4 ,a great] quantity ( flux is requir$ 9 =ge weld+ ?an 9 electric or oxy-acetyl5e processes because ( ! losses 9 ! fire4 ,aft] ! p[d] has be5 appli$ to ! surfaces1 ! "w is return$ to ! fire & heat$ to ! weld+ temp]ature4 ,heat+ ! ,"w4--,aft] be+ sc>f$1 ! two pieces to be weld$ are plac$ 9 ! fire & br\ght to ! correct temp]ature4 ,?is temp]ature c only be recogniz$ by exp]im5t & exp]i5ce4 ,! metal mu/ be j bel[ t po9t at :i* small sp>ks beg9 to be ?r[n out ( ! fire & naturally ?is is a h>d po9t to di/+ui%4 ,at ! weld+ heat ! metal is almo/ ready to fl[ & is ab\t ! consi/5cy ( putty4 ,aga9/ ! backgr\nd ( ! fire & coal ! color appe>s to be a cream or v light yell[ & ! "w feels s(t z x is h&l$4 ,x is absolutely necess>y t bo? p>ts be heat$ uni=mly & s t !y rea* ! weld+ temp]ature at ! same "t4 ,= ?is reason !y %\ld be z close toge!r 9 ! fire z possible & side by side4 ,:5 remov$ to be hamm]$ toge!r1 "t is sav$ if !y are pick$ up 9 su* a way t :5 laid toge!r naturally ! bevel$ surfaces come toge!r4 ,?is makes x necess>y t ! workman rememb] :e!r ! sc>f$ side is up or d[n1 & to assi/ 9 ?is x is a good ?+ to m>k ! sc>f$ side ) *alk or 9 "s o!r noticeable mann]1 s t no mi/ake w be made 9 ! hurry ( plac+ ! "w on ! anvil4 ,! common practice 9 heat+ all[s ! temp]ature to rise until ! small :ite sp>ks are se5 to come f ! fire4 ,any heat+ above ?is po9t w surely result 9 burn+ t w ru9 ! iron or /eel be+ h&l$4 ,! be/ weld+ heat c be disc]n$ by ! appe>ance ( ! metal & its color aft] exp]i5ce has be5 ga9$ ) ?is p>ticul> mat]ial4 ,te/ welds c be made & !n brok51 if possible1 s t ! /r5g? ga9$ ?r\gh diff]5t degrees ( heat c be kn[n be=e attempt+ m important "w4 ,weld+4--,:5 ! "w has rea*$ ! weld+ temp]ature aft] hav+ be5 replac$ 9 ! fire ) ! flux appli$1 ! two p>ts are quickly tapp$ to remove ! loose scale f _! surfaces4 ,!y are !n imm$iately laid across ! top ( ! anvil1 be+ plac$ 9 a diagonal position if bo? pieces are /raight4 ,! l[] piece is re/$ on ! anvil fir/ ) ! sc>f turn$ up & ready to receive ! top piece 9 ! position desir$4 ,! second piece mu/ be laid 9 exactly ! position x is to f9ally occupy because ! two p>ts w /ick toge!r z soon z !y t\* & !y _c well be mov$ aft] hav+ once be5 all[$ to come 9 contact ) ea* o!r4 ,?is "p ( ! "w mu/ be done )\t any unnecess>y loss ( "t because ! comp>atively l[ heat at :i* ! p>ts weld all[s !m to cool bel[ ! work+ temp]ature 9 a few seconds4 ,! greate/ difficulty w be exp]i5c$ 9 )draw+ ! metal f ! fire be=e x becomes burn$ & 9 gett+ x jo9$ be=e x cools bel[ ?is critical po9t4 ,! bevel$ edges ( ! sc>f are1 ( c\rse1 ! fir/ p>ts to cool & ! weld mu/ be made be=e !y rea* a po9t at :i* !y w n jo91 or else ! "w w be defective 9 appe>ance & 9 fact4 ,if ! p>ts be+ h&l$ are ( su* a %ape t !re is dang] ( b5d+ a portion back ( ! weld1 ?is "p may be cool$ by quickly dipp+ x into wat] be=e lay+ ! "w on ! anvil to be jo9$4 ,! workman uses a heavy h& hamm] 9 mak+ ! jo9t1 & 8 help]1 if "o is employ$1 uses a sl$ge4 ,) ! two p>ts ( ! "w 9 place on ! anvil1 ! workman /rikes sev]al light bl[s1 ! fir/ ones be+ at a po9t directly ov] ! c5t] ( ! weld1 s t ! jo9t w />t f ?is po9t & be work$ t[>d ! edges4 ,aft] ! pieces h unit$ ! help] /rikes alt]nate bl[s ) 8 sl$ge1 always /rik+ 9 exactly ! same place z ! la/ /roke ( ! workman4 ,! hamm] bl[s are c>ri$ ne>] & ne>] to ! edges ( ! weld & are made /eadily heavi] z ! "w progresses4 ,! aim dur+ ! fir/ "p ( ! op]ation %\ld be to make a p]fect jo9t1 ) e "p ( ! surfaces unit$1 & too mu* att5tion %\ld n be paid to appe>ance1 at lea/ n en\gh to take any *ance ) ! /r5g? ( ! "w4 ,x w be f\nd1 aft] completion ( ! weld1 t !re has be5 a loss 9 l5g? equal to "o-half ! ?ickness ( ! metal be+ weld$4 ,?is loss is occasion$ by ! burn$ metal & ! scale :i* has be5 =m$4 ,f9i%+ ! ,weld4--,if x is possible to d s1 ! mat]ial %\ld be hamm]$ into ! %ape t x %\ld rema9 ) ! same heat t 0 us$ = weld+4 ,x w usually be f\nd1 h[ev]1 t ! metal has cool$ bel[ ! po9t at :i* x c be work$ to advantage4 ,x %\ld !n be replac$ 9 ! fire & br\ght back to a =g+ heat4 ,illu/ration3 ,figure #eb4--,upsett+ & ,sc>f+ ! ,end ( a ,rod ,:ile %ap+ ! "w at ?is =g+ heat e "p t has be5 at a r$ heat %\ld be hamm]$ ) uni=mly light & ev5 bl[s z x cools4 ,?is re/ores ! gra9 & /r5g? ( ! iron or /eel to a great ext5t & makes ! unavoidable weakness z small z possible4 ,=ms ( ,welds4--,! simple/ ( all welds is t call$ a lap weld4 ,?is is made betwe5 ! ends ( two pieces ( equal size & simil> =m by sc>f+ !m z describ$ & !n lay+ "o on top ( ! o!r :ile !y are hamm]$ toge!r4 ,a butt weld 7,figure #eb7 is made betwe5 ! ends ( two pieces ( %aft or o!r b> %apes by upsett+ ! ends s t !y h a consid]able fl>e & %ap+ ! face ( ! end s t x is slightly high] 9 ! c5t] ?an ar\nd ! edges1 ?is be+ done to make ! c5t]s come toge!r fir/4 ,! pieces are heat$ & pu%$ into contact1 aft] :i* ! hamm]+ is done z ) any o!r weld4 ,illu/ration3 ,figure #ec4--,sc>f+ = a ,t ,weld ,a =m simil> to ! butt weld 9 "s ways is us$ = jo9+ ! end ( a b> to a flat surface & is call$ a jump weld4 ,! b> is %ap$ 9 ! same way z = a butt weld4 ,! flat plate may be left z x is1 b if possible a depression %\ld be made at ! po9t :]e ! %aft is to be plac$4 ,) ! two p>ts heat$ z usual1 ! b> is dropp$ into position & hamm]$ f above4 ,z soon z ! c5t] ( ! weld has be5 made p]fect1 ! jo9t may be f9i%$ ) a full] driv5 all ! way ar\nd ! edge ( ! jo9t4 ,:5 x is requir$ to jo9 a b> to ano!r b> or to ! edge ( any piece at "r angles ! "w is call$ a ,t weld f its %ape :5 complete 7,figure #ec74 ,! end ( ! b> is sc>f$ z describ$ & ! po9t ( ! o!r b> or piece :]e ! weld is to be made is hamm]$ s t x tap]s to a ?9 edge l "o-half ( a circul> depression4 ,! pieces are !n laid toge!r & hamm]$ z = a lap weld4 ,! ends ( heavy b> %apes are (t5 jo9$ ) a ,v1 or cleft1 weld4 ,"o b> end is %ap$ s t x is tap]+ on bo? sides & comes to a broad edge l ! end ( a *isel4 ,! o!r b> is heat$ to a =g+ temp]ature & !n slit op5 9 a l5g?wise direction s t ! ,v-%ap$ op5+ :i* is =m$ w j receive ! po9t$ edge ( ! fir/ piece4 ,) ! "w at weld+ heat1 ! two p>ts are driv5 toge!r by hamm]+ on ! re> ends & ! hamm]+ !n cont9ues z ) a lap weld1 except t ! "w is turn$ ov] to complete bo? sides ( ! jo9t4 ,illu/ration3 ,figure #ed4-,splitt+ ,ends to ,be ,weld$ 9 ,?9 ,"w ,! =ms s f> describ$ all require t ! pieces be laid toge!r 9 ! prop] position aft] removal f ! fire1 & ?is always causes a slight loss ( "t & a consequ5t l[]+ ( ! temp]ature4 ,) v light /ock1 ?is fall ( temp]ature w\ld be s rapid t ! weld w\ld be unsuccessful1 & 9 ?is case ! lock weld is resort$ to4 ,! ends ( ! two pieces to be jo9$ are split = "s di/ance back1 & "o-half ( ea* end is b5t up & ! o!r half d[n 7,figure #ed74 ,! two are !n pu%$ toge!r & plac$ 9 ! fire 9 ?is position4 ,:5 ! weld+ heat is rea*$1 x is only necess>y to take ! "w out ( ! fire & hamm] ! p>ts toge!r1 inasmu* z !y are already 9 ! correct position4 ,o!r =ms ( welds 9 :i* ! p>ts are too small to reta9 _! heat1 c be made by fir/ rivet+ !m toge!r or cutt+ !m s t !y c be tempor>ily fa/5$ 9 any conv5i5t way :5 fir/ plac$ 9 ! fire4 ,,*apt] ,,viii ,,sold]+1 ,,braz+ ,,& ,,!rmit ,,weld+ ,,sold]+ ,common sold] is an alloy ( "o-half lead ) "o-half t91 & is call$ half & half4 ,h>d sold] is made ) two-?irds t9 & "o-?ird lead4 ,^! alloys1 :5 heat$1 are us$ to jo9 surfaces ( ! same or dissimil> metals su* z copp]1 brass1 lead1 galvaniz$ iron1 z9c1 t9n$ plate1 etc4 ,^! metals are easily jo9$1 b ! action ( sold] ) iron1 /eel & alum9um is n s satisfactory & requires great] c>e & skill4 ,! sold] is caus$ to make a p]fect union ) ! surfaces treat$ ) ! help ( heat f a sold]+ iron4 ,! sold]+ iron is made f a piece ( copp]1 po9t$ at "o end & ) ! o!r end atta*$ to an iron rod & wood5 h&le4 ,a flux is us$ to remove impurities f ! jo9t & all[ ! sold] to secure a firm union ) ! metal surface4 ,! iron1 & 9 _m cases ! "w1 is heat$ ) a gasol9e bl[ tor*1 a small gas furnace1 an electric heat] or an acetyl5e & air tor*4 ,! gasol9e tor* :i* is mo/ commonly us$ %\ld be fill$ two-?irds full ( gasol9e ?r\gh ! hole 9 ! bottom1 :i* is clos$ by a screw plug4 ,aft] work+ ! small h& pump = #aj to #bj /rokes1 hold ! palm ( y\r h& ov] ! end ( ! l>ge iron tube on top ( ! tor* & op5 ! gasol9e ne$le valve ab\t a half turn4 ,hold ! tor* s t ! liquid runs d[n into ! cup bel[ ! tube & fills x4 ,%ut ! gasol9e ne$le valve1 wipe ! h&s dry1 & set fire to ! fuel 9 ! cup4 ,j z ! gasol9e fire goes out1 op5 ! gasol9e ne$le valve ab\t a half turn & hold a light$ mat* at ! end ( ! iron tube to ignite ! mixture ( vaporiz$ gasol9e & air4 ,op5 or close ! ne$le valve to secure a flame ab\t #d in*es long4 ,on top ( ! iron tube f :i* ! flame issues !re is a re/ = support+ ! sold]+ iron ) ! copp] "p 9 ! flame4 ,place ! iron 9 ! flame & all[ x to rema9 until ! copp] becomes v hot1 n q r$1 b almo/ s4 ,a new sold]+ iron or "o t has be5 misus$ w h to be t9n$ be=e us+4 ,to d ?is1 take ! iron f ! fire :ile v hot & rub ! tip on "s flux or dip x into sold]+ acid4 ,!n rub ! tip ( ! iron on a /ick ( sold] or rub ! sold] on ! iron4 ,if ! sold] melts (f ! /ick )\t coat+ ! end ( ! iron1 all[ a few drops to fall on a piece ( t9 plate1 !n nil ! end ( ! iron on ! t9 plate ) consid]able =ce4 ,alt]nately rub ! iron on ! sold] & dip into flux until ! tip has a coat+ ( bright sold] = ab\t half an in* f ! end4 ,if ! iron is 9 v bad %ape1 x may be necess>y to scrape or file ! end be=e dipp+ 9 ! flux = ! fir/ "t4 ,aft] ! end ( ! iron is t9n$ 9 ?is way1 replace x on ! re/ ( ! tor* s t ! t9n$ po9t is n directly 9 ! flame1 turn+ ! flame d[n to accompli% ?is4 ,flux4--,! commone/ flux1 :i* is call$ sold]+ acid1 is made by plac+ pieces ( z9c 9 muriatic 7hydro*loric7 acid conta9$ 9 a heavy glass or porcela9 di%4 ,!re w be bubbles & consid]able heat evolv$ & z9c %\ld be add$ until ?is action ceases & ! z9c rema9s 9 ! liquid1 :i* is n[ *loride ( z9c4 ,?is sold]+ acid may be us$ on any metal to be sold]$ by apply+ ) a bru% or swab4 ,= electrical "w1 ?is acid %\ld be made neutral by ! addition ( "o "p ammonia & "o "p wat] to ea* ?ree p>ts ( ! acid4 ,?is neutraliz$ flux w n corrode metal z w ! ord9>y acid4 ,p[d]$ res9 makes a good flux = lead1 t9 plate1 galvaniz$ iron & alum9um4 ,tall[1 olive oil1 beeswax & vasel9e are also us$ = ?is purpose4 ,muriatic acid may be us$ = z9c or galvaniz$ iron )\t ! addition ( ! z9c1 z describ$ 9 mak+ z9c *loride4 ,! addition ( two heap+ teaspoonfuls ( sal ammoniac to ea* p9t ( ! *loride ( z9c is sometimes f\nd to improve its action4 ,sold]+ ,metal ,p>ts4--,all surfaces to be jo9$ %\ld be fitt$ to ea* o!r z accurately z possible & !n ?or\ghly clean$ ) a file1 em]y clo?1 scrat* bu% or by dipp+ 9 lye4 ,"w may be clean$ by dipp+ x into nitric acid :i* has be5 dilut$ ) an equal volume ( wat]4 ,! "w %\ld be heat$ z hot z possible )\t dang] ( melt+1 z ?is causes ! sold] to fl[ bett] & secure a mu* bett] hold on ! surfaces4 ,h>d sold] gives bett] results ?an half & half1 b is m difficult to "w4 ,x is v important t ! sold]+ iron be kept at a high heat dur+ all "w1 o!rwise ! sold] w only /ick to ! surfaces & w n jo9 ) !m4 ,sweat+ is a =m ( sold]+ 9 :i* ! surfaces ( ! "w are fir/ cov]$ ) a ?9 lay] ( sold] by rubb+ !m ) ! hot iron aft] x has be5 dipp$ 9 or t\*$ to ! sold]+ /ick4 ,^! surfaces are !n plac$ 9 contact & heat$ to a po9t at :i* ! sold] melts & unites4 ,sweat+ is mu* to be pref]r$ to ord9>y sold]+ :]e ! =m ( ! "w p]mits x4 ,?is is ! only me?od :i* %\ld ev] be us$ :5 a fitt+ is to be plac$ ov] ! end ( a l5g? ( tube4 ,sold]+ ,holes4--,clean ! surfaces = "s di/ance ar\nd ! hole until !y are bright1 & apply flux :ile hold+ ! hot iron ne> ! hole4 ,t\* ! tip ( ! iron to "s sold] until ! sold] is pick$ up on ! iron1 & !n place ?is sold]1 :i* 0 j pick$ up1 ar\nd ! edge ( ! hole4 ,x w leave ! sold]+ iron & /ick to ! metal4 ,keep add+ sold] 9 ?is way until ! hole has be5 clos$ up by work+ f ! edges & build+ t[>d ! c5t]4 ,aft] ! hole is clos$1 apply m flux to ! job & smoo? ov] ) ! hot iron until !re are no r\gh spots4 ,%\ld ! sold] refuse to fl[ smoo?ly1 ! iron is n hot en\gh4 ,sold]+ ,seams4--,clean back f ! seam or split = at lea/ half an in* all ar\nd & !n build up ! sold] 9 ! same way z 0 done ) ! hole4 ,aft] clos+ ! op5+1 apply m flux to ! "w & run ! hot iron l5g?wise to smoo? ! job4 ,sold]+ ,wires4--,clean all insulation f ! ends to be sold]$ & scrape ! ends bright4 ,lay ! ends p>allel to ea* o!r &1 />t+ at ! middle ( ! clean$ portion1 wrap ! ends ar\nd ea* o!r1 "o be+ wrapp$ to ! "r1 ! o!r to ! left4 ,hold ! hot iron "u ! twi/$ jo9t & apply flux to ! wire4 ,!n dip ! iron 9 ! sold] & apply to ! twi/$ portion until ! spaces betwe5 ! wires are fill$ ) sold]4 ,f9i% by smoo?+ ! jo9t & clean+ away all excess metal by rubb+ ! hot iron l5g?wise4 ,! jo9t %\ld n[ be cov]$ ) a lay] ( rubb] tape & ?is cov]$ ) a lay] ( ord9>y friction tape4 ,/eel & ,iron4--,/eel surfaces %\ld be clean$1 !n cov]$ ) cle> muriatic acid4 ,:ile ! acid is on ! metal1 rub ) a /ick ( z9c & !n t9 ! surfaces ) ! hot iron z direct$4 ,ca/ iron %\ld be clean$ & dipp$ 9 /rong lye to remove grease4 ,wa% ! lye away ) clean wat] & cov] ) muriatic acid z ) /eel4 ,!n rub ) a piece ( z9c & t9 ! surfaces by us+ res9 z a flux4 ,x is v difficult to sold] alum9um ) ord9>y sold]4 ,a special alum9um sold] %\ld be secur$1 :i* is easily appli$ & makes a /rong jo9t4 ,z9c or phosphor t9 may be us$ 9 place ( ord9>y sold] to t9 ! surfaces or to fill small holes or cracks4 ,! alum9um mu/ be ?or\ghly heat$ be=e attempt+ to sold] & ! flux may be ei!r res9 or sold]+ acid4 ,! alum9um mu/ be ?or\ghly clean$ ) dilute nitric acid & kept hot :ile ! sold] is appli$ by =cible rubb+ ) ! hot iron4 ,,braz+ ,?is is a process = jo9+ metal p>ts1 v simil> to sold]+1 except t brass is us$ to make ! jo9t 9 place ( ! lead & z9c alloys :i* =m sold]4 ,braz+ mu/ n be attempt$ on metals ^: melt+ po9t is less ?an t ( %eet brass4 ,two pieces ( brass to be braz$ toge!r are heat$ to a temp]ature at :i* ! brass us$ 9 ! process w melt & fl[ betwe5 ! surfaces4 ,! brass amalgamates ) ! surfaces & makes a v /rong & p]fect jo9t1 :i* is f> sup]ior to any =m ( sold]+ :]e ! "w all[s ?is process to be us$1 & 9 _m cases is ! equal ( weld+ = ! p>ticul> field 9 :i* x applies4 ,braz+ ,heat & ,tools4--,! metal commonly us$ = braz+ w melt at heats betwe5 #acej & #afej ,fahr5heit4 ,to br+ ! p>ts to ?is temp]ature1 v>i\s me?ods are 9 use1 us+ solid1 liquid or gase\s fuels4 ,:ile braz+ may be accompli%$ ) ! fire ( ! blacksmi? =ge1 ?is me?od is seldom satisfactory because ( ! difficulty ( mak+ a suffici5tly clean fire ) smi?+ coal1 & x %\ld n be us$ :5 any?+ else is available4 ,l>ge jobs ( braz+ may be h&l$ ) a *>coal fire built 9 ! =ge1 z ?is fuel produces a v satisfactory & clean fire4 ,! only objection is 9 ! difficulty ( conf9+ ! heat to ! desir$ p>ts ( ! "w4 ,! mo/ satisfactory fire is t f a fuel gas tor* built = ?is "w4 ,^! tor*es are simply =ms ( ,buns5 burn]s1 mix+ ! prop] quantity ( air ) ! gas to br+ ab\t a p]fect combu/ion4 ,hose l9es lead to ! mix+ tube ( ! gas tor*1 "o l9e c>ry+ ! gas & ! o!r air "u a mod]ate pressure4 ,! air l9e is (t5 disp5s$ )1 all[+ ! gas to draw air into ! burn] on ! injector pr9ciple1 mu* ! same z ) illum9at+ gas burn]s = use ) inc&esc5t mantles4 ,valves are provid$ ) :i* ! op]ator may regulate ! am\nt ( bo? gas & air1 & ord9>ily ! quality & int5sity ( ! flame4 ,:5 gas is n available1 rec\rse may be _h to ! gasol9e tor* made = braz+4 ,?is tor* is built 9 ! same way z ! small portable gasol9e tor*es = sold]+ op]ations1 ) ! exception t two regulat+ ne$le valves are incorporat$ 9 place ( only "o4 ,! tor*es are c>ri$ on a framework1 :i* also supports ! "w be+ h&l$4 ,fuel is =c$ to ! tor* f a l>ge tank ( gasol9e into :i* air pressure is pump$ by h&4 ,! tor*es are regulat$ to give ! desir$ flame by means ( ! ne$le valves 9 mu* ! same way z ) any o!r =m ( pressure tor* us+ liquid fuel4 ,ano!r v satisfactory =m ( tor* = braz+ is ! acetyl5e-air comb9ation describ$ 9 ! *apt] on weld+ in/rum5ts4 ,?is tor* gives ! correct degree ( heat & may be regulat$ to give a clean & easily controll$ flame4 ,reg>dless ( ! s\rce ( heat1 ! fire or flame mu/ be adju/$ s t no soot is deposit$ on ! metal surfaces ( ! "w4 ,?is c only be accompli%$ by supply+ ! exact am\nts ( gas & air t w produce a complete burn+ ( ! fuel4 ,) ! braz+ tor*es 9 common use two heads are furni%$1 be+ suppli$ f ! same s\rce ( fuel1 b ) sep>ate regulat+ devices4 ,! tor*es are adju/ably m\nt$ 9 su* a way t ! flames may be direct$ t[>d ea* o!r1 heat+ two sides ( ! "w at ! same "t & all[+ ! pieces to be completely surr\nd$ ) ! flame4 ,except = ! s\rce ( heat1 b "o tool is requir$ = ord9>y braz+ op]ations1 ?is be+ a spatula =m$ by flatt5+ "o end ( a qu>t]-in* /eel rod4 ,! spatula is us$ = plac+ ! braz+ metal on ! "w & = h&l+ ! flux t is requir$ 9 ?is "w z 9 all o!r simil> op]ations4 ,spelt]4--,! metal t is melt$ into ! jo9t is call$ spelt]4 ,:ile ?is "n orig9ally appli$ to b "o p>ticul> grade or composition ( metal1 common use has ext5d$ ! mean+ until x is g5]ally appli$ to all grades4 ,spelt] is v>i\sly compos$ ( alloys conta9+ copp]1 z9c1 t9 & antimony1 ! mixture employ$ dep5d+ on ! "w to be done4 ,! diff]5t grades are ( v>y+ h>dness1 ! h>d] k9ds melt+ at high] temp]atures ?an ! s(t ones & produc+ a /rong] jo9t :5 us$4 ,! reason = n us+ h>d spelt] 9 all cases is ! increas$ difficulty ( work+ x & ! fact t its melt+ po9t is s ne> to "s ( ! metals braz$ t !re is great dang] ( melt+ ! "w z well z ! spelt]4 ,! h>de/ grade ( spelt] is made f ?ree-f\r?s copp] ) "o-f\r? z9c & is us$ = work+ on malleable & ca/ iron & = /eel4 ,?is h>d spelt] melts at ab\t #afej & is correspond+ly difficult to h&le4 ,a spelt] suitable = work+ ) copp] is made f equal p>ts ( copp] & z9c1 melt+ at ab\t #adjj ,fahr5heit1 #ejj bel[ ! melt+ po9t ( ! copp] itself4 ,a /ill s(t] braz+ metal is compos$ ( half copp]1 ?ree-eigh?s z9c & "o-eigh? t94 ,?is grade is us$ = fa/5+ brass to iron & copp] & = work+ ) l>ge pieces ( brass to brass4 ,= braz+ ?9 %eet brass & light brass ca/+s1 a metal is us$ :i* conta9s two-?irds t9 & "o-?ird antimony4 ,! l[ melt+ po9t ( ?is la/ composition makes x v easy to "w ) & ! dang] ( melt+ ! "w is v slight4 ,h[ev]1 z might be expect$1 a comp>atively weak jo9t is secur$1 :i* w n /& any great /ra94 ,all ( ! above braz+ metals are us$ 9 p[d] =m s t !y may be appli$ ) ! spatula :]e ! jo9t is expos$ on ! outside ( ! "w4 ,9 case x is necess>y to braze on ! inside ( a tube or any deep recess1 ! spelt] may be plac$ on a flat rod long en\gh to rea* to ! f>!/ po9t4 ,by di/ribut+ ! spelt] at ! prop] po9ts along ! rod x may be plac$ at ! "r po9ts by turn+ ! rod ov] aft] ins]t+ into ! recess4 ,flux4--,9 ord] to remove ! oxides produc$ "u braz+ heat & to all[ ! braz+ metal to fl[ freely into place1 a flux ( "s k9d mu/ be us$4 ,! commone/ flux is simply a pure calc9$ borax p[d]1 t is1 a borax p[d] t has be5 heat$ until practically all ! wat] has be5 driv5 (f4 ,calc9$ borax may also be mix$ ) ab\t #ae p] c5t ( sal ammoniac to make a satisfactory flux+ p[d]4 ,x is absolutely necess>y to use flux ( "s k9d & a "p ( :atev] is us$ %\ld be made into a pa/e ) wat] s t x c be appli$ to ! jo9t to be braz$ be=e heat+4 ,! rema9d] ( ! p[d] %\ld be kept dry = use dur+ ! op]ation & aft] ! heat has be5 appli$4 ,prep>+ ! ,"w4--,! surfaces to be braz$ are fir/ ?or\ghly clean$ ) files1 em]y clo? or s& pap]4 ,if ! "w is greasy1 x %\ld be dipp$ into a ba? ( lye or hot soda wat] s t all trace ( oil is remov$4 ,! p>ts are !n plac$ 9 ! relation to ea* o!r t !y are to occupy :5 ! "w has be5 complet$4 ,! edges to be jo9$ %\ld make a secure & tight fit1 & %\ld mat* ea* o!r at all po9ts s t ! smalle/ possible space is left betwe5 !m4 ,?is fit %\ld n be s tight t x is necess>y to =ce ! "w into place1 nei!r %\ld x be loose en\gh to all[ any consid]able space betwe5 ! surfaces4 ,! molt5 spelt] w p5etrate betwe5 surfaces t wat] w fl[ betwe5 :5 ! "w & spelt] h bo? be5 br\ght to ! prop] heat4 ,x is1 ( c\rse1 necess>y t ! two p>ts h a suffici5t numb] ( po9ts ( contact s t !y w rema9 9 ! prop] relative position4 ,! "w is plac$ on ! surface ( ! braz+ table 9 su* a position t ! flame f ! tor*es w /rike ! p>ts to be heat$1 & ) ! jo9t 9 su* a position t ! melt$ spelt] w fl[ d[n ?r\gh x & fill e possible "p ( ! space betwe5 ! surfaces "u ! action ( gravity4 ,t means t ! edge ( ! jo9t mu/ be upp]mo/ & ! crack to be fill$ mu/ n lie horizontal1 b at ! greate/ slant possible4 ,bett] ?an any degree ( slant w\ld be to h ! l9e ( ! jo9t v]tical4 ,! "w is brac$ up or clamp$ 9 ! prop] position be=e comm5c+ to braze1 & x is be/ to place fire brick 9 su* positions t x w be impossible = cool+ draughts ( air to rea* ! heat$ metal %\ld ! flame be remov$ tempor>ily dur+ ! process4 ,9 case !re is a l>ge body ( iron1 /eel or copp] to be h&l$1 x is (t5 advisable to place *>coal ar\nd ! "w1 ignit+ ?is ) ! flame ( ! tor* be=e />t+ to braze s t ! metal w be ma9ta9$ at ! correct heat )\t dep5d+ entirely on ! tor*4 ,:5 h&l+ brass pieces hav+ ?9 sections !re is dang] ( melt+ ! brass & caus+ x to fl[ away f "u ! flame1 ) ! result t ! "w is ru9$4 ,if1 9 ! judgm5t ( ! workman1 ?is may happ5 ) ! p>ticul> job 9 h&1 x is well to build up a m\ld ( fire clay back ( ! ?9 p>ts or pref]ably back ( ! :ole piece1 s t ! metal w h ! necess>y support4 ,?is m\ld may be made by mix+ ! fire clay into a /iff pa/e ) wat] & !n pack+ x aga9/ ! piece to be support$ tightly en\gh s t ! =m w be reta9$ ev5 if ! metal s(t5s4 ,braz+4--,) ! "w 9 place1 x %\ld be well cov]$ ) ! pa/e ( flux & wat]1 !n heat$ until ?is flux boils up & runs ov] ! surfaces4 ,spelt] is !n plac$ 9 su* a position t x w run into ! jo9t & ! heat is cont9u$ or increas$ until ! spelt] melts & fl[s 9 betwe5 ! two surfaces4 ,! flame %\ld surr\nd ! "w dur+ ! heat+ s t outside air is exclud$ z f> z is possible to prev5t excessive oxidization4 ,:5 h&l+ brass or copp]1 ! flame %\ld n be direct$ s t its c5t] /rikes ! metal squ>ely1 b s t x glances f "o side or ! o!r4 ,direct+ ! flame /raight aga9/ ! "w is (t5 ! cause ( melt+ ! pieces be=e ! op]ation is complet$4 ,:5 braz+ two diff]5t metals1 ! flame %\ld play only on ! "o t melts at ! high] temp]ature1 ! l[] melt+ "p receiv+ its heat f ! o!r4 ,?is avoids ! dang] ( melt+ "o be=e ! o!r rea*es ! braz+ po9t4 ,! heat %\ld be cont9u$ only long en\gh to cause ! spelt] to fl[ into place & no long]4 ,prolong$ heat+ ( any metal c d no?+ b oxidize & weak5 x1 & ?is practice %\ld be avoid$ z mu* z possible4 ,if ! spelt] melts into small globules 9 place ( fl[+1 x may be caus$ to spread & run into ! jo9t by lightly tapp+ ! "w4 ,m dry flux may be add$ ) ! spatula if ! tapp+ does n produce ! desir$ result4 ,excessive use ( flux1 especially t[>d ! end ( ! "w1 w result 9 a v h>d surface on all ! "w1 a surface :i* w be extremely difficult to f9i% prop]ly4 ,?is tr\ble w be pres5t to a c]ta9 ext5t anyway1 b x may be less5$ by a vigor\s scrap+ ) a wire bru% j z soon z ! "w is remov$ f ! fire4 ,if all[$ to cool be=e clean+1 ! f9al appe>ance w n be z good z ) ! surplus metal & scale remov$ imm$iately ^u complet+ ! job4 ,aft] ! "w has be5 clean$ ) ! bru% x may be all[$ to cool & f9i%$ to ! desir$ %ape1 size & surface by fil+ & poli%+4 ,:5 fil$1 a v ?9 l9e ( brass %\ld appe> :]e ! crack 0 at ! beg9n+ ( ! "w4 ,if x is desir$ to avoid a squ>e %\ld] & fill 9 an angle jo9t to make x r\nd+1 ! fill+ is be/ accompli%$ by w9d+ a coil ( v ?9 brass wire ar\nd ! "p ( ! "w t projects & !n caus+ ?is to fl[ itself or else all[ ! spelt] to fill ! spaces betwe5 ! lay]s ( wire4 ,copp] wire may also be us$ = ?is purpose1 ! spaces be+ fill$ ) melt$ spelt]4 ,,!rmit ,,weld+ ,! process ( weld+ :i* makes use ( ! great heat produc$ by oxyg5 comb9+ ) alum9um is kn[n z ! ,!rmit process & 0 p]fect$ by ,dr4 ,hans ,golds*midt4 ,! process1 :i* is controll$ by ! ,golds*midt ,!rmit ,company1 makes use ( a mixture ( f9ely p[d]$ alum9um ) an oxide ( iron call$ by ! trade "n1 ,!rmit4 ,! reaction is />t$ ) a special ignition p[d]1 su* z b>ium sup]oxide & alum9um1 & ! oxyg5 f ! iron oxide comb9+ ) ! alum9um1 produc+ a mass ( sup]heat$ /eel at ab\t #ejjj degrees ,fahr5heit4 ,aft] ! reaction1 :i* takes f4 #cj seconds to a m9ute1 ! molt5 metal is drawn f ! crucible on to ! surfaces to be jo9$4 ,its extreme heat fuses ! metal & a p]fect jo9t is ! result4 ,?is process is suit$ = weld+ iron or /eel p>ts ( comp>atively l>ge size4 ,prep>ation4--,! p>ts to be jo9$ are ?or\ghly clean$ on ! surfaces & = sev]al in*es back f ! jo9t1 aft] :i* !y are support$ 9 place4 ,! surfaces betwe5 :i* ! metal w fl[ are sep>at$ f #a_/d to #a in*1 dep5d+ on ! size ( ! p>ts1 b cutt+ or drill+ "p ( ! metal away4 ,aft] ?is sep>ation is made = all[+ ! entrance ( new metal1 ! effects ( contraction ( ! molt5 /eel are c>$ = by preheat+ adjac5t p>ts or by =c+ ! ends ap>t ) w$ges & jacks4 ,! am\nt ( ?is la/ sep>ation mu/ be det]m9$ by ! %ape & proportions ( ! p>ts 9 ! same way z w\ld be done = any o!r class ( weld+ :i* heats ! p>ts to a melt+ po9t4 ,yell[ wax1 :i* has be5 w>m$ until pla/ic1 is !n plac$ ar\nd ! jo9t to =m a coll>1 ! wax completely fill+ ! space betwe5 ! ends & be+ provid$ ) v5t holes by imb$d+ a piece ( /\t cord1 :i* is pull$ out aft] ! wax cools4 ,a reta9+ m\ld 7,figure #ee7 made f %eet /eel or fire brick is !n plac$ ar\nd ! p>ts4 ,?is m\ld is !n fill$ ) a mixture ( "o "p fire clay1 "o "p gr\nd fire brick & "o "p fire s&4 ,^! mat]ials are well mix$ & moi/5$ ) en\gh wat] s t !y w pack4 ,?is mixture is !n plac$ 9 ! m\ld1 fill+ ! space betwe5 ! walls & ! wax1 & is pack$ h>d ) a ramm] s t ! mat]ial =ms a wall sev]al in*es ?ick betwe5 any po9t ( ! m\ld & ! wax4 ,! mixture mu/ be plac$ 9 ! m\ld 9 small quantities & pack$ tight z ! fill+ progresses4 ,illu/ration3 ,figure #ee4--,!rmit ,m\ld ,con/ruction ,?ree or m op5+s are provid$ ?r\gh ?is m\ld+ mat]ial by ! ins]tion ( wood or pipe =ms4 ,"o ( ^! op5+s w lead f ! l[e/ po9t ( ! wax patt]n & is us$ = ! introduction ( ! preheat+ flame4 ,ano!r op5+ leads f ! top ( ! m\ld into ?is preheat+ gate1 op5+ into ! preheat+ gate at a po9t ab\t "o in* f ! wax patt]n4 ,op5+s1 call$ ris]s1 are !n provid$ f ea* ( ! high po9ts ( ! wax patt]n to ! top ( ! m\ld1 ^! ris]s end+ at ! top 9 a %all[ bas94 ,! molt5 metal comes up into ^! ris]s & c>es = contraction ( ! ca/+1 z well z avoid+ defects 9 ! coll> ( ! weld4 ,aft] ! m\ld+ mat]ial is well pack$1 ^! gate patt]ns are tapp$ lightly & )drawn1 except 9 ! case ( ! metal pipes :i* are plac$ at po9ts at :i* x w\ld be impossible to )draw a patt]n4 ,preheat+4--,! ends to be weld$ are br\ght to a bright r$ heat by introduc+ ! flame f a tor* ?r\gh ! preheat+ gate4 ,! tor* mu/ use ei!r gasol9e or k]os5e1 & n crude oil1 z ! crude oil deposits too mu* c>bon on ! p>ts4 ,preheat+ ( o!r adjac5t p>ts to c>e = contraction is done at ?is "t by an additional tor* burn]4 ,! heat+ flame is />t$ g5tly at fir/ & gradually increas$4 ,! wax w melt & may be all[$ to run out ( ! preheat+ gate by remov+ ! flame at int]vals = a few seconds4 ,! heat is cont9u$ until ! m\ld is ?or\ghly dri$ & ! p>ts to be jo9$ are br\ght to ! r$ heat requir$4 ,?is leaves a m\ld j ! %ape ( ! wax patt]n4 ,! heat+ gate %\ld !n be plugg$ ) a s& core1 iron plug or piece ( fitt$ fire brick1 & back$ up ) sev]al %ovels full ( ! m\ld+ mixture1 well pack$4 ,illu/ration3 ,figure #ef4--,!rmit ,crucible ,plug4 ,a1 ,h>d burn magnesia /one2 ,b1 ,magnesia ?imble2 ,c1 ,refractory s&2 ,d1 ,metal disc2 ,e1 ,asbe/os wa%]2 ,f1 ,tapp+ p9 ,!rmit ,metal4--,! reaction takes place 9 a special crucible l9$ ) magnesia t>1 :i* is bak$ at a r$ heat until ! t> is driv5 (f & ! magnesia left4 ,?is l9+ %\ld la/ f twelve to fifte5 reactions4 ,?is magnesia l9+ ends at ! bottom ( ! crucible 9 a r+ ( magnesia /one & ?is r+ c>ries a magnesia ?imble ?r\gh :i* ! molt5 /eel passes on its way to ! m\ld4 ,x w usually be necess>y to r5ew ?is ?imble aft] ea* reaction4 ,?is l[] op5+ is clos$ be=e fill+ ! crucible ) !rmit by means ( a small disc or iron c>ry+ a /em1 :i* is call$ a tapp+ p9 7,figure #ef74 ,?is p91 ,f1 is plac$ 9 ! ?imble ) ! /em ext5d+ d[n ?r\gh ! op5+ & expos+ ab\t two in*es4 ,! top ( ?is p9 is cov]$ ) an asbe/os1 wa%]1 ,e1 !n ) ano!r iron disc4 ,d1 & f9ally ) a lay] ( refractory s&4 ,! crucible is tapp$ by knock+ ! /em ( ! p9 upw>ds ) a spade or piece ( flat iron ab\t f\r feet long4 ,! *>ge ( !rmit is add$ by plac+ a few h&fuls ov] ! refractory s& & !n p\r+ 9 ! balance requir$4 ,! am\nt ( !rmit requir$ is calculat$ f ! wax us$4 ,! wax is weigh$ be=e & aft] fill+ ! entire space t ! !rmit w occupy4 ,?is does n mean only ! wax coll>1 b ! space ( ! m\ld ) all gates fill$ ) wax4 ,! numb] ( p\nds ( wax requir$ = ?is fill+ multipli$ by #be w give ! numb] ( p\nds ( !rmit to be us$4 ,to ?is quantity ( !rmit %\ld be add$ ,i p] c5t ( pure manganese1 #a p] c5t nickel !rmit & #ae p] c5t ( /eel pun*+s4 ,x is necess>y1 :5 m ?an #aj p\nds ( !rmit w be us$1 to mix /eel pun*+s n exce$+ #c_/h in* diamet] by #a_/h in* ?ick ) ! p[d] 9 ord] to suffici5tly ret>d ! int5sity ( ! reaction4 ,half a teaspoonful ( ignition p[d] is plac$ on top ( ! !rmit *>ge & ignit$ ) a /orm mat* or piece ( r$ hot iron4 ,! cov] %\ld be imm$iately clos$ on ! top ( ! crucible & ! op]ator %\ld get away to a safe di/ance because ( ! metal t may be ?r[n out ( ! crucible4 ,aft] all[+ ab\t #cj seconds to a m9ute = ! reaction to take place & ! slag to rise to ! top ( ! crucible1 ! tapp+ p9 is /ruck f bel[ & ! molt5 metal all[$ to run into ! m\ld4 ,! m\ld %\ld be all[$ to rema9 9 place z long z possible1 pref]ably ov] night1 s z to anneal ! /eel 9 ! weld1 b 9 no case %\ld x be di/urb$ = sev]al h\rs aft] p\r+4 ,aft] remov+ ! m\ld1 drill ?r\gh ! metal left 9 ! ris] & gates & knock ^! sections (f4 ,no "p ( ! coll> %\ld be remov$ unless absolutely necess>y4 ,,*apt] ,,ix ,,oxyg5 ,,process ,,= ,,removal ,,( ,,c>bon ,until rec5tly ! me?ods us$ = remov+ c>bon deposits f gas eng9e cyl9d]s 7 v impractical & unsatisfactory4 ,! job meant dismantl+ ! motor1 te>+ out all p>ts1 & scrap+ ! pi/ons & cyl9d] walls by h&4 ,! "w 0 nev] done ?or\ghly4 ,x requir$ h\rs ( "t to d x1 & !n !re 0 always ! dang] ( injur+ ! inside ( ! cyl9d]s4 ,^! me?ods h be5 to a l>ge ext5t sup]s$$ by ! use ( oxyg5 "u pressure4 ,! v>i\s devices t are be+ manufactur$ are kn[n z c>bon remov]s1 dec>boniz]s1 etc41 & l>ge numb]s ( !m are 9 use 9 ! automobile & gasol9e traction motor indu/ry4 ,outfit4--,! oxyg5 c>bon clean] consi/s ( a high pressure oxyg5 cyl9d] ) automatic r$uc+ valve1 usually con/ruct$ on ! diaphragm pr9ciple1 ?us assur+ positive regulation ( pressure4 ,?is valve is fitt$ ) a pressure gauge1 rubb] hose1 dec>boniz+ tor* ) %ut (f & flexible tube = ins]tion into ! *amb] f :i* ! c>bon is to be remov$4 ,!re %\ld also be an asbe/os swab = swabb+ out ! inside ( ! cyl9d] or o!r *amb] ) k]os5e previ\s to />t+ ! op]ation4 ,! action consi/s 9 simply burn+ ! c>bon to a f9e du/ 9 ! pres5ce ( ! /ream ( oxyg51 ?is du/ be+ !n bl[n out4 ,op]ation4--,! foll[+ are in/ructions = op]at+ ! clean]3-- 7#a7 ,close valve 9 gasol9e supply l9e & />t ! motor1 lett+ x run until ! gasol9e is exhau/$4 7#b7 ,if ! cyl9d]s be ,t or ,l head1 remove ei!r ! inlet or ! exhau/ valve cap1 or a sp>k plug if ! cap is tight4 ,if ! cyl9d]s h ov]head valves1 remove a sp>k plug4 ,if any sp>k plug is !n rema9+ 9 ! cyl9d] x %\ld be remov$ & an old "o or an iron pipe plug sub/itut$4 7#c7 ,raise ! pi/on ( ! cyl9d] fir/ to be clean$ to ! top ( ! compression /roke & cont9ue ?is f cyl9d] to cyl9d] z ! "w progresses4 7#d7 ,9 motors :]e c>bon has be5 burn$ h>d1 ! cyl9d] int]ior %\ld !n be swabb$ ) k]os5e be=e proce$+4 ,"w ! swab1 saturat$ ) k]os5e1 ar\nd ! inside ( ! cyl9d] until all ! c>bon has be5 moi/5$ ) ! oil4 ,?is same swab may be us$ to ignite ! gas 9 ! cyl9d] 9 place ( us+ a mat* or tap]4 7#e7 ,make all connections to ! oxyg5 cyl9d]4 7#f7 ,ins]t ! tor* nozzle 9 ! cyl9d]1 op5 ! tor* valve gradually & regulate to ab\t two lbs4 pressure4 ,manipulate ! nozzle inside ! cyl9d] & light a mat* or o!r flame at ! op5+ s t ! c>bon />ts to burn4 ,cov] ! v>i\s po9ts )9 ! cyl9d] & :5 !re is no fur!r burn+ ! c>bon has be5 remov$4 ,! regulat+ & oxyg5 tank valves are op]at$ 9 exactly ! same way z = weld+ z previ\sly expla9$4 ,x %\ld be c>efully not$ t :5 ! pi/on is up1 ready to />t ! op]ation1 bo? valves mu/ be clos$4 ,!re w be a consid]able display ( sp>ks :ile ?is op]ation is tak+ place1 b !y w n set fire to ! grease & oil4 ,c>e %\ld be us$ to see t no gasol9e is ab\t4 ,,index ,acetyl5e filt]+ g5]ators 9 tanks pip+ prop]ties ( purification ( ,acetyl5e-air tor*es ,air oxyg5 f ,alloys table ( ,alloy /eel ,alum9um alloys weld+ ,anneal+ ,anvil ,arc weld+1 electric ma*9es ,asbe/os1 use (1 9 weld+ ,babbitt ,b5d+ pipes & tubes ,bessem] /eel ,bevel+ ,brass weld+ ,braz+ electric heat & tools spelt] ,bronze weld+ ,butt weld+ ,calcium c>bide ,c>bide /orage (1 ,fire ,und]writ]s' ,rules to wat] g5]ator ,c>bon removal by oxyg5 process ,case h>d5+ /eel ,ca/ iron weld+ ,*ampf]+ ,*>g+ g5]ator ,*lorate ( pota% oxyg5 ,conductivity ( metals ,copp] alloys weld+ ,crucible /eel ,cutt+1 oxy-acetyl5e tor*es ,dissolv$ acetyl5e ,electric arc weld+ ,electric weld+ tr\bles & rem$ies ,expansion ( metals ,flame1 weld+ ,fluxes = braz+ = sold]+ ,=ge fire practice tools tuv]e con/ruction ( weld+ weld+ prep>ation welds1 =ms ( ,=g+ ,gas hold]s ,gases1 heat+ p[] ( ,g5]ator1 acetyl5e c>bide to wat] con/ruction ,g5]ator location ( op]ation & c>e ( ov]heat+ requirem5ts wat] to c>bide ,g]man silv] ,gloves ,goggles ,h& =g+ ,h>d5+ /eel ,heat treatm5t ( /eel ,hildebr&t process ,hose ,injectors1 adju/] ,iron ca/ grades ( malleable ca/ wr\ght ,jump weld ,lap weld+ ,lead ,l9de process ,liquid air oxyg5 ,magnalium ,malleable iron weld+ ,melt+ po9ts ( metals ,metal alloys1 table ( ,metals *>act]i/ics ( conductivity ( expansion ( heat treatm5t ( melt+ po9ts ( t5sile /r5g? ( weight ( ,nickel ,nozzle sizes1 tor* ,op5 he>? /eel ,oxy-acetyl5e cutt+ weld+ practice ,oxyg5 cyl9d]s weight ( ,pipes1 b5d+ ,plat9um ,preheat+ ,removal ( c>bon by oxyg5 process ,resi/ance me?od ( electric weld+ ,re/oration ( /eel ,rods1 weld+ ,safety devices ,sc>f+ ,sold] ,sold]+ flux holes seams /eel & iron wires ,spelt] ,spot weld+ ,/eel alloys ,bessem] crucible heat treatm5t ( op5 he>? re/oration ( t5sile /r5g? ( weld+ ,/r5g? ( metals ,tank valves ,tap]+ ,tables ( weld+ in=mation ,temp]+ /eel ,!rmit metal preheat+ prep>ation weld+ ,t9 ,tor* acetyl5e-air c>e con/ruction cutt+ high pressure l[ pressure m$ium pressure nozzles practice ,valves1 regulat+ tank ,wat] to c>bide g5]ator ,weld+ alum9um brass bronze butt ca/ iron copp] electric electric arc flame =ge in=mation & tables in/rum5ts lap malleable iron mat]ials practice1 oxy-acetyl5e rods spot /eel table !rmit tor*es v>i\s metals wr\ght iron ,wr\ght iron weld+ ,z9c