,transcriber's ,note3 ,subscripts are   
preceded by an acute accent mark 2      
italic text is enclosed in underscores4 
,illustration            ,,machinery',s 
,,reference ,,series        ,,each      
,,number ,,is ,,one ,,unit ,,in ,a      
,,complete ,,library ,,of ,,machine     
,,design    ,,and ,,shop ,,practice     
,,revised ,,and ,,republished ,,from    
,,machinery        ,,number #aji        
,,die ,,casting                         
,,dies--,,machines--,,methods      ,by  
,,chester ,l4 ,,lucas                   
,,contents          ,die ,casting       
#c        ,making ,dies for             
,die-,casting ,machines            #ae  
,van ,wagner ,mfg4 ,co4's ,die-,casting 
,practice      #bg        ,copyright1   
#aiac1 ,the ,industrial ,press1         
,publishers of ,,machinery1    #di-ee   
,lafayette ,street1 ,new ,york ,city    
,,chapter ,i    ,,die ,,casting         
,die-casting1 a comparatively recent    
method for producing finished  castings1
 is rapidly proving itself an important 

factor in the  economical manufacture of
 interchangeable parts for adding       
machines1  typewriters1 telephones1     
automobiles and numerous other products 
where  it is essential that the parts be
 nicely finished and accurate in        
dimensions4 ,the term 8die-casting0 is  
self-explanatory1 meaning 8to  cast by  
means of dies02 described briefly1 the  
process consists of  forcing molten     
metal into steel dies1 allowing it to   
cool in them1 and  then opening the dies
 and removing the finished casting4 ,it 
is the  purpose of this treatise to give
 a general outline of the die-casting   
process1 showing its possibilities and  
limitations1 and also to give  a        
description of the die-casting machinery
 and its operation1 of  the fundamental 
principles involved1 and of the methods 
used in the  die-making4 ,illustrative  
examples of the best types of dies1     
based on  results obtained from actual  
experience1 will also be given4         
,origin of ,die ,casting    ,the origin 

of the die-casting process is somewhat  
difficult to  ascertain4 ,we may look   
into the history of type founding and   
find  that away back in #ahch1 the first
 casting machine for type1 invented  by 
,bruce1 was a machine that involved the 
principles of die-casting  as it is     
practiced to-day4 ,more recently1 in    
#ahhe1 ,otto ,mergenthaler  brought out 
the linotype machine4 ,this machine is a
 good example of  a die-casting machine4
 ,however1 as we interpret the word     
to-day1  die-casting is a broader term  
than type-casting or linotyping1        
although  its development without doubt 
is due to the success of the linotype   
machine4 ,it is doubtful if die-casting1
 properly speaking1 was  originated     
until about fifteen years ago1 and it is
 certain that it is  only during the    
past few years that the activities in   
this line have  been very noticeable4   
,one of the first experiments in the    
direction of die-casting was  undertaken
 to get out some rubber mold parts      

cheaply enough to leave a  profit on a  
job that was beginning to look dubious  
from the financial  side4 ,the molds    
were for making rubber plates about     
three inches  square and one-eighth inch
 thick1 the top side of which was       
decorated  with fine raised scroll work2
 it was this latter feature that gave   
the trouble4 ,after wasting much time   
and money trying to stamp the  mold     
parts1 a metal-tight box was made as    
shown in ,figs4 #a and #b with  a block 
screwed in it1 the purpose of which was 
to shape the mold  impression and impart
 to it the scroll design4 ,as shown1 the
 ends of  the box were removable1 being 
screwed on4 ,this box was placed under  
a screw press and a straight plunger    
that just filled the top of the  box was
 fitted to the head of the press4 ,after
 the two were lined up1  molten type    
metal was poured into the box1 and as   
soon as the metal  had cooled to the    
8mushy0 state1 the ram of the press was 
forced down  as shown in ,fig4 #b4      

,next1 the ends of the box were removed1
 the screw  holding the block taken out1
 and the die-casting pushed from the    
box4  ,the object in having the inclined
 side to the box was to produce a  piece
 shaped with the proper inclination for 
its position in the final  mold used for
 casting the rubber plates4 ,the        
illustrations give an idea  of the      
compression that took place4 ,the       
die-casting was found to be  sharp at   
the corners and free from flaws1 and the
 scroll work came up  in fine shape4    
,naturally the rest of the mold parts   
were made in the  same way and the job  
turned from failure into success4       
,illustration3      ,fig4 #a4 ,an ,early
 ,experiment in ,die ,casting--,before  
,applying ,pressure      ,fig4 #b4 ,an  
,early ,experiment in ,die              
,casting--,after ,applying ,pressure    
,from such simple experiments as these1 
the die-casting industry has  developed 
to its present stage4 ,in view of the   
advances that have been  made in        

die-casting1 it is singular that there  
are to-day only about  a dozen concerns 
in the business in this country1 but as 
the subject  becomes better understood1 
and the possibilities of the process are
  realized1 the demand for this class of
 castings will result in many  other    
firms going into the work1 and it is not
 improbable that a large  number of     
factories will install die-casting      
plants of their own to aid  them in     
producing better work in a more         
economical way4      ,advantages1       
,possibilities and ,limitations of ,die 
,casting    ,the greatest advantage of  
die-casting is the fact that the        
castings  produced are completely and   
accurately finished when taken from the 
dies4 ,when we say completely1 we mean  
that absolutely no machining is         
required after the piece has been cast1 
as it is ready to slip into its  place  
in the machine or device of which it is 
to be a part4 ,when we say  accurately1 
we mean that each piece will come from  

the die an exact  counterpart of the    
last one2 and if the dies are carefully 
made1 the  castings will be accurate    
within #j4jja inch on all dimensions1   
whether  they are outside measurements1 
diameters of holes or radii4 ,all holes 
are cast and come out smoother than they
 could be reamed2 lugs and gear  teeth  
are cast in place2 threads1 external and
 internal1 and of any  desired pitch can
 be cast4 ,oil grooves can be cast in   
bearings1 and1 in  a word1 any piece    
that can be machined can be die-cast4   
,the saving in machining works both     
ways2 not only is all machine work      
eliminated by the one operation of      
casting1 but the machine tools and  the 
workmen necessary for their operation   
and up-keep are dispensed  with1 the    
expense of building jigs and fixtures is
 stopped2 and no  cutters1 reamers1 taps
 or drills are required for this branch 
of the  production4 ,in addition1 the   
labor required for operating the casting
  machines may be classed as unskilled4 

,no matter how intricate and  exacting  
the machine work on a piece has been1   
and how skillful a  workman was required
 to produce the work when machine-made1 
the same  result may be brought about by
 die-casting1 and usually the work is   
excelled1 and1 excluding the die-making1
 unskilled men can make the  parts4     
,from a metallurgical standpoint a      
die-casting is superior to a            
sand-casting on account of its density1 
strength and freedom from  blow-holes4  
,also1 when the hot metal comes in      
contact with the cool  dies1 it forms a 
8skin0 similar to the scale on an iron  
sand-casting4  ,as the die-casting      
requires no machining after leaving the 
dies1 this  skin increases the wearing  
qualities of the casting4    ,the       
possibilities of die-casting are        
numerous4 ,by this method of            
manufacturing it is possible and        
practical to cast pieces that could  not
 possibly be machined4 ,it is an        
every-day occurrence to make  castings  

with inserted parts of another metal1   
as1 for instance1 a  zinc wheel with a  
steel hub4 ,it is also possible to make 
babbitt  bearings that are harder and   
better than can be made in any other    
way4  ,often there are two or more parts
 of a device that have formerly been    
made separately1 machined and assembled1
 that can be die-cast as one  piece4 ,in
 such cases the saving in production is 
very great4 ,figures  and letters may be
 cast sunken or in relief on wheels for 
counting  or printing1 and of course    
ornamentation may be cast on pieces that
  require exterior finish4 ,as to size1 
there is no definite limit to the  work 
that can be cast4 ,one job that is being
 done at the present time  is a disk #af
 inches in diameter with a round flange 
#a inch in diameter1  around the rim4   
,illustration3 ,fig4 #c4 ,examples of   
,die-castings    8,there is no great    
gain without some small loss10 is just  
as true of a  process like die-casting  
as it is of anything else4 ,the         

limitations of  this work are few1      
however1 and they are here given so as  
to state the  situation fairly4         
,generally speaking1 a part should not  
be considered  for die-casting if there 
are but few pieces required1 because the
 cost  of the dies would usually be     
prohibitive4 ,often1 however1 it happens
  that because of the large amount of   
accurate machine work being done on  a  
machine part1 it is economical to make a
 die for the comparatively  small number
 of parts required and die-cast them4 ,a
 case illustrating  this phase of the   
matter recently occurred in actual      
practice4 ,in  getting out an order of  
two hundred vending machines1 it was    
decided  to try die-casting on a part   
that was difficult to machine4 ,the dies
  were expensive1 costing #bjj1 and as  
there were only #bjj pieces to be  cast1
 the die cost per piece was one dollar2 
but even with that initial  handicap1 it
 was found that on account of the       
difficult machining that  had formerly  

been required1 the die-cast parts       
effected a large saving1  and of course 
the results were superior4    ,a rough  
part that would require little or no    
machining should not  be die-cast1      
because pound for pound1 the die-casting
 metals cost  more than cast iron or    
steel4 ,the casting machine cannot make 
parts  as rapidly or of as hard metals  
as the punch press or the automatic     
screw machine4 ,for this latter reason a
 part that necessarily must be  made of 
brass1 iron or steel1 cannot be         
die-cast1 although mixtures             
approximately equal in strength to iron 
and brass are readily die-cast4  ,to    
give added strength to a die-cast part  
it is often advisable to  add webs and  
ribs or to insert brass or iron pins at 
points that are  weak or subject to hard
 wear4 ,roughly speaking1 it is the part
 that  has required a good deal of      
accurate machine operations that shows  
the  greatest difference in cost when   
die-cast1 and sometimes the saving is   

as great as #hj per cent4      ,the     
,metals used in ,die ,casting    ,the   
metals that produce the best            
die-castings are alloys of lead1 tin1   
zinc1 antimony1 aluminum and copper1 and
 the bulk of the die-castings  made at  
the present time are mixtures of the    
first four of these  metals4 ,from them1
 compositions may be made that will meet
 the  requirements of nearly any part4  
,for parts that perform little or no    
actual work1 save to 8lend  their       
weight10 such as balance weights1       
novelties and ornaments for  show       
windows1 etc41 a mixture consisting     
principally of lead1 often  stiffened   
with a little antimony1 is used4 ,there 
is but little strength  to this metal1  
but it is used because of its weight and
 low cost4  ,for parts that are subject 
to wear1 such as phonograph1 telephone1 
gas-meter and adding machine parts1 an  
alloy composed of zinc1 tin and  a small
 amount of copper is used4 ,this alloy  
may be plated or japanned1  and is a    

good metal to use on general work4      
,another metal1 used chiefly for casting
 pieces that have delicate  points in   
their design but are not subjected to   
hard wear1 consists  principally of tin 
alloyed with lead and zinc to suit the  
requirements  of the work4 ,this mixture
 casts freely1 and the finished castings
 come  out exceptionally clean4 ,still  
another metal1 used chiefly for casting 
pieces that have letters and figures for
 printing1 is similar to the  standard  
type metal--#e parts lead and #a part   
antimony2 but if there are  teeth cast  
on the sides of the printing wheel a    
harder mixture will be  required to give
 longer life to the gears4    ,the      
following mixtures are typical of       
die-casting or 8white brass0  alloys3   
copper1 #aj parts2 zinc1 #hc parts2     
aluminum1 #b parts2 tin1 #e  parts4     
,another is copper1 #f parts2 zinc1 #ij 
parts2 aluminum1 #c parts2  tin1 #a     
part4 ,another containing antimony is   
copper1 #e parts2 zinc1 #he  parts2 tin1

 #e parts2 antimony1 #e parts4          
,shonberg's patented alloy is  copper1  
#c parts2 zinc1 #hg parts2 tin1 #aj     
parts4 ,alloys containing #ae to  #dj   
per cent copper and #fj to #he per cent 
zinc are brittle1 having low  strength  
and low ductility4 ,an alloy of #h per  
cent copper1 #ib per cent  zinc has     
greater resilience and strength but not 
the ductility of cast  zinc4            
,aluminum may be cast1 but it is a      
difficult metal to run into thin  walls 
and fine details2 it plays1 however1 an 
important part in some  good mixtures   
used for die casting4 ,experiments are  
now being conducted  for die-casting    
manganese bronze1 and it is said that   
some very good  castings have already   
been made4 ,its wearing qualities are so
 valuable  that it is particularly      
desirable for making die-castings4      
,the ,die-casting ,machine    ,the three
 important requisites for good          
die-casting are the machine1  the dies  
and the metal4 ,the casting machine is  

fully as essential as  either of the    
other requisites1 and although there are
 a number of  different styles of       
casting machines in use1 each of which  
has its  advantages over the others1    
especially in the eyes of their         
respective  designers1 the fundamental  
principles upon which they all operate  
are  the same4 ,in each there is the    
melting pot and the burner1 the cylinder
  and the piston for forcing the metal  
into the dies1 and the dies with  the   
opening and closing device4 ,in some    
machines pressure is applied to  the    
metal by hand1 in others power is used1 
and in still another class  the metal is
 forced into the dies with compressed   
air4 ,the provisions  for opening and   
closing the dies vary in the different  
machines2 there  are various means      
employed for cutting the sprue1 and the 
styles of  heaters are numerous4    ,one
 or two of the largest firms in the     
die-casting industry have  automatic    
casting machines for turning out        

duplicate work in large  quantities very
 rapidly4 ,these machines are           
complicated and are only  profitable on 
large quantities of work1 and for that  
reason their  use is not extensive4 ,in 
general1 their operating principles are 
the  same as in the case of the hand    
machines1 but provision is made for     
automatically opening and closing the   
dies1 compressing the metal1 and        
ejecting the castings4      ,the ,soss  
,die-casting ,machine    ,the ,soss     
die-casting machine1 manufactured and   
sold by the ,soss  ,manufacturing ,co41 
,brooklyn1 ,n4 ,y41 was the first       
die-casting machine  to be placed on the
 open market4 ,this machine is shown in 
,figs4 #d and  #e1 and in section in    
,fig4 #f4 ,the ,soss ,manufacturing ,co4
 originally  manufactured invisible     
hinges exclusively4 ,at the advent of   
the  die-casting era1 they commenced to 
make these hinges from die-castings1    
and placed orders with a leading        
die-casting concern amounting to        

thousands of dollars each year4 ,after  
the die-cast hinges had been on  the    
market for a short time1 complaints     
commenced to come in1 some to  the      
effect that the hinges were breaking and
 others that the hinges  were corroding4
 ,either of these faults was serious    
enough to blast the  reputation of the  
hinge1 but the first trouble1 breakage1 
was the more  important4 ,examination of
 the broken hinges showed that the      
castings  were porous and full of flaws1
 and as the makers of the castings      
could not produce castings sufficiently 
strong for the hinges1 ,mr4  ,soss      
started to experiment for himself4 ,this
 experimenting led to the  production of
 the ,soss die-casting machine4         
,illustration3 ,fig4 #d4 ,general ,view 
of the ,soss ,die-casting ,machine      
,referring to the illustrations ,figs4  
#e and #f1 ,a is the base and frame  of 
the machine1 ,b is the heating chamber  
located at one end of the  machine1 and 
within this heating chamber is the tank 

,c1 shown in ,fig4  #f4 ,this tank      
contains the metal from which the       
die-castings are made1  and the metal is
 heated by the burners ,d4 ,these       
burners are fed by  air and gas through 
piping on the side of and beneath the   
furnace4 ,to  facilitate lighting the   
burners and inspecting their condition  
at any  time1 there is an opening 7not  
shown7 through the firebrick lining of  
the furnace and the outer iron wall1 on 
a level with the top of the  burners4   
,there is also another opening through  
the furnace wall to  allow the gases due
 to the combustion to escape4 ,through  
the bottom of  the tank1 well to the    
inner side of the furnace1 runs the     
cylinder ,e4  ,below the bottom of the  
tank1 the cylinder makes a right-angle  
turn1  extending through the furnace    
wall and terminating just outside of the
  wall4 ,the orifice of this cylinder is
 controlled by gate ,f4 ,in that  part  
of the cylinder that extends upward into
 the tank1 there is an  opening ,g that 

allows the molten metal to run into the 
cylinder from  the tank4 ,working in    
this cylinder1 is the piston ,h1 that is
 used in  forcing the metal into the    
dies4 ,the compression lever ,i1 hinged 
over  the inner furnace wall1 is kept   
normally raised by spring pressure1 and 
is connected to the piston by means of  
the link ,j4    ,illustration3 ,fig4 #e4
 ,working ,parts of the ,soss           
,die-casting ,machine    ,at the        
opposite end of the machine from the    
furnace1 is the mechanism  for operating
 the dies4 ,this mechanism consists of a
 pair of square  rods ,k1 upon which are
 mounted the sleeves ,l4 ,these sleeves 
have  a long bearing surface and are    
attached to the die-plate ,m4 ,lever  ,n
 at the end of the operating mechanism  
controls the movement of  these sleeves 
by means of links ,o4 ,upon these       
sleeves is mounted a  secondary set of  
sleeves ,p1 attached to the other       
die-plate ,q1  and whose movement is    
controlled by lever ,r1 through links   

,s4  ,this second set of sleeves is free
 to travel with the first set1 and  in  
addition has an independent movement of 
its own on the primary  sleeves4 ,it is 
the function of lever ,r to bring       
die-plate ,q up  to die-plate ,m by     
means of links ,s and sleeves ,p2 and it
 is  the function of lever ,n to bring  
both of the die-plates up to the  outlet
 of the cylinder by means of links ,o   
and sleeves ,l4 ,this  system of        
sleeve-mounting is one of the           
distinctive patented features  of the   
,soss machine4 ,the orifice of the      
cylinder ,e is conical in  shape and    
exactly fits the cup-shaped opening in  
die-plate ,m1 so  that when the two are 
brought together1 the joint is metal    
tight4 ,at  the center of this opening1 
and extending through the die-plate ,m1 
is an opening that leads to the dies    
mounted on the inner faces of the  two  
die-plates1 and a continuation of this  
opening extends through  die-plate ,q in
 which the sprue-cutter ,u works4       

,attached to the  outer side of this    
die-plate are two slotted brackets4 ,in 
the slot of  one of these is pivoted the
 lever ,t1 and in the slot in the       
opposite  bracket are bolted two stops  
that limit the motion of the lever4     
,this  lever operates the sprue cutter  
,u1 that works through the opening in   
die-plate ,q4 ,the sprue-cutting        
mechanism is best shown in ,figs4 #e and
  #f4 ,at the left of ,fig4 #e may be   
seen a rubber hose connected to the air 
piping4 ,this hose is used for cleaning 
out the dies after each casting         
operation4      ,operation of the       
,die-casting ,machine    ,the metal for 
the die-casting machine is mixed in the 
proper  proportions for the work in hand
 by means of a separate furnace1 before 
being poured into the tank of the       
machine itself4 ,the burners are        
lighted and the dies are set up on the  
two die-plates4 ,as soon as the  machine
 has 8warmed up10 so that the metal is  
in a thoroughly melted  condition1 the  

sprue-cutting lever ,t is thrown back1  
leaving a clear  passageway to the die  
cavities4 ,lever ,r is pulled backward1 
thus  bringing die-plate ,q up to       
die-plate ,m1 which operation closes    
the two halves of the die4 ,then lever  
,n is thrown forward1 thereby  bringing 
the closed die up to the body of the    
machine1 with the nozzle  in close      
contact with the outlet of the cylinder4
 ,next1 the gate ,f  is opened1 and the 
man at the compression lever ,i gives   
the lever a  quick1 hard pull1 forcing  
the metal in the cylinder downward and  
into  the dies4 ,the molten metal       
literally 8squirts0 into the dies4 ,gate
 ,f  is now closed2 lever ,n is pulled  
back to remove the dies from the        
cylinder outlet2 and the sprue-cutting  
lever ,t is pushed forward1  cutting off
 the sprue and pushing it out of the    
nozzle into the kettle  placed beneath  
it4 ,the lever ,r is pushed forward1 and
 a finished  casting is ejected from the
 dies4    ,an important advantage that  

this machine has over other die-casting 
machines is the fact that the metal for 
the castings is taken from the  bottom  
of the melting pot1 whereas most other  
machines use metal from  the top of the 
tank4 ,at the bottom of the tank the    
metal is always the  best1 as it is free
 from impurities and dross2 hence1 there
 is little  chance for the formation of 
blow-holes4 ,a handful of rosin thrown  
into the melting tank occasionally helps
 to keep the metal clean1  but the metal
 nearest the surface always contains    
more or less foreign  matter4           
,illustration3 ,fig4 #f4 ,section of    
,soss ,die-casting ,machine    ,while   
this description of the operation of the
 die-casting machine may  convey the    
idea that the process is a slow one1 as 
a matter of fact1  the time required is1
 on the average1 not over a minute and a
 half  for turning out a finished       
casting4 ,with the ejection of the      
casting  from the dies1 the product is  
completed1 in theory2 but in practice   

there are always a few small thin fins1 
caused by the air vents or by           
improperly fitted portions of the dies4 
,it is1 however1 but the work  of a few 
seconds to break off these fins1 and    
unless there are many of  them1 or they 
are excessively thick1 they are         
detrimental neither to  the quality nor 
the quantity of finished castings4      
,points on the ,operation of the        
,die-casting ,machine    ,we have now   
taken up the description and general    
operation of the  die-casting machine1  
but like every other machine1 there are 
numerous  little kinds and practices in 
its working the observing of which makes
  the difference between good and poor  
die-casting4 ,some of these points  are 
here given4    ,the casting machine is  
best operated by three men1 one of whom 
attends  to the compression lever and   
the metal supply in the tank4 ,the other
  two men stand on each side of the     
die-end of the machine1 and it is  their
 duty to operate the sprue-cutter1 open 

the dies and remove the  finished       
casting1 clean the dies with air and    
close them1 throw back  the die-plates  
to their casting position over the      
cylinder outlet1 and  do any other work 
incident to the operation of the        
machine4 ,while it  requires three men  
to operate a die-casting machine in the 
best manner1  the man who attends to the
 compression lever has a good deal of   
spare  time between strokes1 and if two 
or even three of the machines are       
conveniently placed1 one man can easily 
pull levers for all three4    ,the metal
 should be kept just above the melting  
point and at a  uniform temperature4 ,if
 the metal is worked too cold1 the      
result will  manifest itself in castings
 that are full of seams and creases1 and
 it  will be difficult to 8fill0 the    
thin places in the dies4 ,if1 on the    
other hand the metal is allowed to get  
too hot1 the die will throw  excessively
 long fins1 the castings will not cool  
as quickly in the  die1 and consequently

 they cannot be made as rapidly4 ,on    
account of  the importance of keeping   
the metal at a uniform heat1 the fresh  
metal  that is added to that in the tank
 from time to time1 is kept heated in  a
 separate furnace4 ,therefore1 when the 
metal in the tank gets low1 the  new    
supply does not reduce the temperature  
of the metal being worked4  ,some       
casters use a thermometer to indicate   
the heat of the metal4    ,casting-dies 
require lubrication frequently4 ,just   
how often they should  be lubricated    
depends on the shape of the die1 the    
composition of the  casting metal1 and  
the general performance of the dies4    
,beeswax is  the common lubricant1 and  
the lubrication consists in merely      
rubbing  the cake over the surfaces of  
the dies that come in contact with the  
casting metal4 ,in die-casting large    
parts1 the dies must be kept cool  by   
some artificial means1 for hot dies are 
conducive to slow work and  poor        
castings4 ,to reach this end1 large dies

 are sometimes drilled and  piped so    
that water may be circulated through    
them to keep them cool4    ,in the ,soss
 machine1 the burners are so placed that
 the metal in the  cylinder is kept at a
 slightly higher heat than that in the  
tank  proper4 ,this condition is brought
 about by having the cylinder directly  
over the burners4 ,the value of this    
feature lies in the fact that  gas is   
not wasted in heating the entire tank   
full of metal to this  higher heat1 but 
still the metal under compression is at 
the required  temperature4 ,the gas     
consumption of the average die-casting  
machine is  about #ajj cubic feet per   
hour4    ,the speed at which            
die-castings may be produced varies with
 the size of  the castings being made1  
the composition of the metal being cast1
 and  the style of dies that must be    
employed4 ,in many cases1 in            
die-casting1  separate brass or steel   
pieces are used1 that must be placed in 
the  dies before each operation so that 

they will be inserted in and become  a  
part of the finished casting4 ,the dies 
may be difficult of operation  on       
account of draft problems or pins and   
screws that must be inserted  in the    
dies and removed from each casting      
before another can be made4  ,these     
different types of dies will be more    
fully described in the next  chapter4   
,taken as a whole1 from ten to sixty    
pieces per hour are the  maximum limits 
for speed in die-casting1 and with a    
well-working die1  of simple            
construction1 a speed of forty pieces   
per hour is considered  good production4
 ,it is possible1 however1 when the     
castings to be  produced are small in   
size and simple in shape1 to gate a     
number of  them together1 or rather to  
construct the dies so that six or more  
castings may be made at once4 ,by this  
means it is often possible to  cast five
 or six thousand pieces per day of ten  
hours1 on a hand  die-casting machine4  
,,chapter ,,ii    ,,making ,,dies ,,for 

,,die-,,casting ,,machines      ,the    
making of casting-dies calls for        
ingenuity and skill of the highest      
order on the part of the die-maker4     
,there is probably no class of          
die-making in which the work produced is
 more faithful to the dies1  both in    
showing up the little details in the    
making that reflect credit  on the dies1
 and in exposing the defects and        
shortcomings in the  workmanship1 if    
there be any4 ,the castings from        
casting-dies or molds  as they are      
sometimes called1 may be produced in    
dimensions down to  ten-thousandths for 
accuracy if necessary1 and once the dies
 are made  the castings will not vary in
 the slightest degree1 if the working   
conditions are kept uniform4    ,in     
spite of the close work required in     
making casting-dies1 the work is  very  
fascinating4 ,perhaps it is on account  
of this accuracy2 possibly  it is on    
account of the fact that they are made  
from machine steel2  but most likely it 

is because there are no hardening       
troubles to be  contended with4 ,another
 factor that makes the work interesting 
is the  ingenuity required in the work1 
for almost every die-maker1 if he is    
worthy of the name1 likes to figure out 
and plan for the best way of  building a
 die for a difficult job4      ,general 
,principles of ,casting-die ,making     
,casting-dies1 or molds1 have little in 
common with sand molds4 ,it  is true    
that the dies for die-casting are       
composed of two parts  corresponding to 
the cope and nowel of the sand mold1 but
 they are  so different in every other  
way that no benefit would result from a 
comparison4    ,generally speaking1     
casting-dies are made of machine steel2 
the parts  which are exceptions are the 
heavy bases and frames1 which are made  
of  cast iron1 and the dowel pins and   
small cores1 usually made of tool       
steel4 ,except in rare instances1 there 
are no hardened parts about a           
casting-die2 this is the case because   

the melting points of some of the       
alloys that are die-cast are high enough
 to draw the temper from any  hardened  
parts of the dies4    ,the ideal die is 
simple in construction1 with as few     
parts as  practicable2 the castings     
should be easily ejected and should come
  from the dies as nearly free from fins
 as possible4 ,to meet these            
requirements in the best way is the     
proposition that confronts the          
ingenuity of the die-maker4 ,as the die 
is primarily in two parts1 there  must  
be a parting line on the casting4 ,this 
line is always placed at  the point that
 will permit the casting to be ejected  
from the dies in  the easiest manner    
possible1 bearing in mind the effect the
 joint will  have on the appearance of  
the finished casting2 this is a point   
far  less important than with sand      
casting1 for1 if the dies are properly  
made this seam will be barely           
perceptible4 ,when it is practicable to 
do so1 it is wise to have the parting   

line come on an edge of the             
die-casting4 ,draft is unnecessary on   
the straight 8up-and-down0  places1 but 
of course it is impossible to draw any  
parts that are  undercut4 ,means must be
 provided for ejecting the casting from 
the  dies after completion and it is    
usually done by means of ejector pins1  
though frequently it is better to have  
the bottom of the die or some  other    
section movable and do the ejecting on  
the same principle that  is used on     
drawing dies of the compound type4 ,on  
close work1 shrinkage  plays an         
important part1 and the amount of       
shrinkage varies from #j4jjb  to #j4jjg 
of an inch per inch4 ,aluminum shrinks  
the greatest amount1  ,parsons white    
brass shrinks considerably1 while tin   
shrinks but little4  ,thus1 it may be   
easily seen that to figure the shrinkage
 allowance for  an alloy that contains  
three or four metals with different     
shrinkages1  requires judgment4 ,to     
prevent the air from 8pocketing10 air   

vents are  necessary at frequent        
intervals around the die-cavity4 ,these 
vents are  made by milling a flat       
shallow cut from the die-cavity across  
the face  of the die to the outside     
edges of the block4 ,from  inch to  inch
  is the usual width and from #j4jjc to 
#j4jje of an inch1 the customary  depth1
 varying with the size and shape of the 
die in question4    ,illustration3 ,fig4
 #g4 ,disk cast in ,simple ,casting-die 
,the dies or molds for die-casting are  
of various styles1 as are also          
punch-press dies1 and it would be       
difficult to lay down specific  rules   
for their classification4 ,there are the
 plain dies1 without  complications of  
any kind2 slide dies with one or more   
slides2 dies  for bearings1 both of the 
8half-round0 and of the 8whole-round0   
types2  dies for gated work2 and many   
other less important classes4 ,then     
there  are dies that have features that 
belong to more than one of these  types1
 so that it is easily seen that to      

decide upon the style of die  that would
 be best for a given piece of work      
requires a good deal of  experience4    
,some of the most important of these    
types can best be shown  by illustrating
 dies made in the various styles1       
showing1 step by step1  how the dies are
 made and assembled4 ,to begin with1    
consider the making  of a casting-die of
 the very simplest form4    ,in ,fig4 #g
 is shown a plain flat disk made by     
die-casting4 ,in actual  practice1 a die
 would not be made for such a simple    
piece1 unless  there were some features 
about it that would prevent it being    
made  on a screw machine or with press  
tools4 ,it might have a cam groove  cut 
in one of its flat sides1 the sides     
might be covered with scroll  work1     
there might be gear teeth around its    
circumference1 or a hundred  and one    
other conditions to make die-casting a  
desirable method of  manufacturing4 ,all
 these complications are omitted for the
 sake of  simplifying this initial      

description of a casting-die4           
,illustration3 ,fig4 #h4 ,simple        
,casting-die for ,casting ,block shown  
in  ,fig4 #g    ,fig4 #h shows the die  
for this piece in plan and sectional    
elevation4  ,a is a square cast-iron    
frame1 made from a single casting4 ,this
 frame  or box1 as it is generally      
called1 is planed on the top and bottom 
only4 ,next1 the two die-halves ,b and  
,c are shaped up from machine  steel4   
,in this casting-die1 and in the        
majority of others1 these  die blocks   
are square4 ,the lower half of the die  
,b is held to the  cast-iron frame by   
fillister head screws1 set in           
counterbored holes1  thus sinking the   
screw-heads under the surface of the    
block4 ,the upper  half of the die ,c is
 located upon ,b by dowel pins driven   
into ,b  which have a sliding fit in the
 reamed holes in ,c4 ,this being done1  
the die-half ,b is fixed to the         
faceplate of the lathe and the recess   
bored for the die-cavity4 ,this         

operation is a simple one in this case1 
for it is merely a straight hole        
one-half inch deep and three inches in  
diameter4 ,of course this recess must be
 carefully finished with a tool  that   
has been stoned up to a sharp edge1     
using lard oil4 ,emery cloth  should be 
used as little as possible4 ,it is      
unnecessary to give this  hole draft1   
but it must be free from ridges or marks
 that would prevent  the casting from   
being pushed out4 ,if the faces of the  
dies are spotted  with a small piece of 
box wood or rawhide held in the drill   
press and  kept charged with flour      
emery1 the die-casting will reproduce   
this  8bird's-eye0 finish and the       
appearance will well repay the few      
minutes  additional time that it will   
take4 ,the spotting should be done with 
dry  emery 7without oil7 to get the     
brightest finish4 ,the upper die-half ,c
  is simply ground on its working face4 
,the outside corners and edges of  the  
faces of both die-halves should be well 

rounded off so as to insure  the absence
 of slight dents or rough places that   
might prevent the dies  from fitting    
perfectly4    ,the ejecting mechanism   
must next be considered4 ,lever ,d1     
pivoted  from bracket ,e1 has a steel   
pin ,f that engages in the elongated    
hole in bracket ,g1 so that an upward   
pull of the lever ,d raises  bracket ,g1
 which is attached to ejector-pin plate 
,h4 ,this plate is  a loose fit over the
 guide screws ,i that are attached to   
the lower  die-half ,b4 ,the ejector    
pins ,j1 four in number1 in this die1   
are  riveted into the ejector-pin plate1
 and they work through holes drilled    
and reamed through the lower die-half4  
,the ends of these pins must be         
finished off so as to lie perfectly     
flush with the inside of the die  when  
ready for operation and1 of course1 they
 must be a sliding fit in  the holes in 
the die4    ,an important feature of a  
casting-die is the sprue cutter1 shown  
in  this die at ,k4 ,if the disk for    

which this die was made1 had had a  hole
 or central opening of any kind1 the    
sprue cutter would best be  operated at 
that point2 but1 as this disk is plain1 
the sprue cutter  must be placed at the 
edge4 ,at the outside of the die-cavity1
 as shown  in ,fig4 #h1 the opening for 
the sprue cutter is laid out1 drilled   
and filed to shape4 ,it is obvious that 
the side of the sprue cutter  adjacent  
to the die must fit the outline of the  
die perfectly1 so that  there will be no
 break in the appearance of the casting4
 ,the opening  for it is extended       
through the upper die-half1 and from a  
point  of an  inch from the inside face 
of the die this hole is flared out      
nearly as  large as the opening through 
the die-plate of the machine4 ,of course
  the apperture in the upper die-half   
must be no larger than the opening      
through the die-plate2 otherwise the    
sprue could not be pushed out4 ,the     
sprue cutter itself is a long rod1 whose
 section is of the same shape  and size 

as the openings just made1 and it is    
connected to the sprue  cutting         
mechanism of the machine4 ,of course it 
is unnecessary to shape  the entire     
length of the sprue cutter to size2     
after the working end is  milled to     
shape for a distance of six or eight    
inches1 the rest of the  rod may be left
 round4 ,the sprue cutter is finished   
first1 after which  both the openings in
 the die are fitted to it2 and while the
 fit should  be metal tight1 it must be 
perfectly free to slide4    ,the dies   
are mounted on the die-plates of the    
casting machine by means  of straps1    
much the same as bolsters are held on   
punch press beds4 ,the  position of the 
die on the die-plate must be such that  
the opening for  the sprue cutter will  
line up with the nozzle at the outlet of
 the  cylinder4 ,at the time of casting1
 the position of the sprue cutter is  as
 shown in the illustration of this die1 
,fig4 #h4 ,in this position  there is   
room for the metal to enter the         

die-cavity1 and yet there is  but a     
small amount of metal to be cut off and 
pushed back after the die  has been     
filled with metal4    ,with slight      
modifications1 the above style of die   
may be used for  die-casting any piece  
that will draw or pull out of a two-part
 die4 ,if  holes must be cast through   
the piece1 it is only necessary to add  
core  pins to the lower die ,b1 a point 
that will be more fully described       
later4 ,it is unnecessary to add that   
both halves of the die may be  utilized 
in making the cavity for the die1 should
 they be needed4 ,also1  it is often    
easier to machine out the recess larger 
than is needed1 and  set in pieces in   
which parts of the outline of the       
die-casting have  been formed4 ,gear    
teeth are put in the die in this way2 a 
broach is cut  similar to the gear      
desired1 then hardened and driven       
through a piece  of steel plate which is
 afterward fitted to its place in the   
die4      ,slide ,dies    ,the die      

illustrated in ,fig4 #i is one of the   
most successful of the  various types of
 casting-dies1 and if properly made is  
an interesting  piece of die work4 ,the 
principal use of this particular style  
of die1  called a slide die1 is to cast 
parts like the one shown in ,fig4 #aj1  
which is a disk similar to the one which
 the last die described was  to cast1   
except that it has raised letters at the
 edge and a hole in  the center4 ,it is 
obvious that the die last described1    
7,fig4 #h71 would  not do for disks or  
other pieces having projections or      
depressions  around their edges1 as1 for
 instance1 printing or counting wheels  
with  raised or sunken characters1 or   
grooved pulleys4 ,briefly1 this style   
of die is similar to the simple         
casting-die1 except that slides are     
provided1 to the required number1 which 
form the edge of the casting4  ,a die   
for a plain grooved pulley would require
 but two slides1 while  a die for a     
printing wheel with forty letters around

 its edge would  necessitate forty      
slides1 one for each of the letters4    
,the die about to  be described1 shown  
in ,fig4 #i1 was made to cast a wheel   
with six raised  letters4    ,referring 
to ,fig4 #i1 ,d is the cast-iron box or 
frame1 ,e1 the lower  die1 and ,f the   
upper die4 ,in making the lower         
die-half1 the stock is  first shaped to 
size and doweled to the blank for the   
upper die-half1  and the holes for      
attaching to the frame are drilled4 ,for
 the sake of  clearness1 these holes and
 screws are omitted from the            
illustration as  are also the vents1    
since they have been fully explained4   
,the lower  die is next strapped to a   
faceplate1 trued up1 and bored out      
nearly  to the diameter of the body of  
the piece to be cast1 exclusive of the  
raised letters4 ,the depth of this      
recess is equal to the thickness of  the
 printing wheel plus #c_/af inch to     
allow for the cam ring ,g that is  used 
to reciprocate the slides of the die4   

,the cam ring is made large  enough to  
cover the die-cavity as well as the     
slides that surround  it1 with an       
allowance of an inch or two for the cam 
slots ,h4 ,the six  slides ,i are made  
long enough to have good bearing        
surfaces4 ,with the  size of the cam    
ring determined1 the die is next bored  
out to receive  this cam ring and the   
last inch of the recess is carried down 
to the  depth of the die cavity so as to
 make an ending space for the slots     
that the slides are to work in4 ,the die
 is now taken from the faceplate  and   
the slots for the slides laid out4      
,illustration3 ,fig4 #i4 ,slide ,die for
 ,casting the ,printing ,wheel shown  in
 ,fig4 #aj    ,these slots may be milled
 or shaped1 but milling is to be        
preferred4  ,the next step is the making
 and fitting of the slides1 which are of
  machine steel1 having a good sliding  
fit in the slots4 ,the six slides  are  
fitted in position and left with the    
ends projecting into the die  proper4   

,the slots ,h are next profiled in the  
cam ring ,g1 and the  pins ,j that work 
in them are made and driven into the    
holes in the  slides4 ,with the slides  
and cam ring in place1 the cam ring is  
rotated  to bring all the slides to     
their inner position where they are held
  temporarily by means of the cam ring  
and temporary screws4 ,the die-half     
with the slides thus clamped in the     
inner or closed position1 is set up  on 
the lathe faceplate and the die-cavity  
indicated up and bored out to  the      
finish size1 which operation also       
finishes the ends of the slides  to the 
proper radius4 ,the die may now be taken
 down and the slides  removed to engrave
 the letters upon their concave ends4   
,the engraving  can be done in the best 
manner on a ,gorton engraving machine1  
but if  such a machine is not available 
they may be cut in by hand4 ,stamping   
should never be resorted to for putting 
in the letters1 because the  stock      
displacement would be so great that it  

would be impossible to  refinish the    
surface to its original condition4      
,before fitting the  cam ring1 an       
opening must be milled in the die to    
allow the handle to  be rotated the     
short distance necessary4 ,after the cam
 ring has been  fitted1 it is held in by
 the four small straps ,k1 attached by  
screws  to the lower die-half at the    
corners4    ,illustration3 ,fig4 #aj4   
,printing ,wheel cast in a ,slide ,die  
,the sprue cutter1 which is not shown1  
is operated through the hole  in the    
center of the piece and is1 of course1  
round in this die4  ,its action is the  
same as was the one previously          
described1 and the  ejecting device is  
similar1 with the exception that the    
brackets ,l  that are attached to the   
ejector-pin plate ,m1 are widely        
separated so  as to make room for the   
sprue cutter that works through a hole  
in the  plate ,m4      ,die for ,casting
 with ,inserted ,pieces    ,for making  
die-castings that are to have pieces of 

another metal  inserted1 it is necessary
 to have a die with provisions for      
receiving  the metal blank and holding  
it firmly in position while the metal is
  being cast around it1 and of course   
the piece must be held in such a  manner
 that it can be easily withdrawn from   
the die with the finished  casting4     
,the die illustrated in ,fig4 #aa is for
 a part that is used as a swinging      
weight1 shown in ,fig4 #ab4 ,the upper  
part of the piece is made from a  sheet 
steel punching1 so as to lighten this   
part of the piece as well  as to give   
increased strength1 especially at the   
hole at the pivoted  end of the work4   
,the cast portion of the piece is       
slotted lengthwise1  as the illustration
 shows2 and three holes pass through the
 casting1  piercing the sides of the    
slot4 ,in addition to showing the method
 of  making dies for inserted pieces1   
this die shows the principles of  simple
 coring4    ,illustration3 ,fig4 #aa4   
,casting-die for ,making ,castings with 

,inserted  ,pieces like that shown in   
,fig4 #ab    ,in making this die1 two   
machine-steel blanks are planed up for  
the  upper and lower halves of the die1 
,a and ,b1 the lower die being  made    
nearly twice as thick as the upper die  
because it is in this part  that the    
most of the die-cavity will be made4 ,in
 this lower half of  the die the stock  
is milled out to the same shape as the  
outline of  the plan view of the        
casting1 being carried down to the exact
 depth  of the thickness of the casting4
 ,from the wide end of this recess the  
stock is milled or shaped out in a      
parallel slot to the outside of the     
die-block4 ,at the bottom of the side of
 this wide slot are ,t-slots  to guide  
the slide ,e that is to work in this    
opening4 ,the side is  milled and fitted
 to the ,t-slots and opening in the die1
 but is left  considerably longer than  
the finish size4 ,next1 the slide is    
mounted  on the faceplate of a lathe and
 turned out on the end with the proper  

radius and a tongue to form the slot    
that is to be in the curved end  of the 
casting4 ,at the outer end of the slide 
is left a lug that is  drilled and      
tapped for the operating lever ,f that  
reciprocates the  slide1 using the stud 
in bracket ,k as a fulcrum4    ,two     
pieces of machine steel are next shaped 
and finished up to form the  chamfered  
part of the casting and to locate the   
inserted steel punching  in the die4    
,the combined thickness of these pieces 
,c and ,d is equal  to the thickness of 
the casting1 less the thickness of the  
inserted  piece4 ,it is now an easy     
matter to seat section ,d in the bottom 
of  the milled part of the lower        
die-half1 and to locate section ,c in   
its  proper position on the upper half4 
,a pilot pin ,m is fitted in ,d to  hold
 the steel punching in position by means
 of the hole that is in the  extreme    
upper end of the punching4 ,the pilot   
pin extends through this  hole into a   
corresponding hole in section ,c4 ,at   

the lower end of the  steel part that is
 inserted1 there are two holes the      
object of which  is to secure the       
punching to the die-casting1 for the    
molten metal  runs through these holes1 
practically riveting the die-casting to 
the  inserted piece4    ,illustration3  
,fig4 #ab4 ,die-cast ,weight with       
,inserted ,sheet-steel  ,punching       
,provision has now been made for holding
 the sheet-metal part that is  to be    
inserted1 and the cavity has been       
completed for the casting1  including   
the tongue at the end2 it now remains to
 describe the manner  of forming the    
holes that pierce the casting through   
the slotted  portion4 ,in the lower     
die-half the positions of the three     
holes ,h are  laid out1 drilled and     
reamed4 ,then1 with the two die-halves  
together  and the slide clamped at its  
inner position1 the holes are           
transferred  through the slide and the  
upper die4 ,this being done1 it is an   
easy  matter to make core pins and drive

 them into the upper die at the two  end
 holes1 the center hole being taken care
 of by the sprue cutter ,l  that will be
 described later4 ,the core pins should 
be a nice sliding  fit through the slide
 and in the holes in the lower die1 into
 which  they should extend from a       
quarter to half an inch4 ,in addition to
  coring the holes1 these pins act as a 
lock to hold the slide ,e in its  proper
 position at the time of casting4       
,the sprue cutter ,l is most            
conveniently operated in the center     
hole1  thus doing away with the core pin
 that would otherwise be required4 ,the 
sprue cutter needs little description in
 this die1 for as in the slide  die1 it 
is merely a plain round rod that fits   
closely in the holes  through the dies  
and slide4 ,the ejector mechanism is the
 same in this  die as in the dies       
already described2 therefore further    
description is  unnecessary4            
,illustration3 ,fig4 #ac4 ,casting-die  
for the ,half-round ,bearing shown in   

,fig4 #ad    ,the operation of this die 
is very simple4 ,the sheet-steel piece  
is laid  in the recess in the open die1 
being located by the pin ,m4 ,slide  ,e 
is thrown in by means of lever ,f1 and  
the dies are closed4 ,at  the time of   
casting1 the sprue cutter in is the     
position shown in  the sketch1 being    
nearly through the die-cavity4 ,as      
before explained1  this position admits 
the molten metal to pass into the       
die-cavity1 but  still leaves very      
little sprue to be cut off after the    
die-casting is  completed4 ,it should be
 stated that the steel piece that is    
inserted  must be perfectly flat and    
free from burrs that would prevent the  
die-halves from coming together         
properly4      ,bearing ,dies           
,bearing dies are one of the most       
important of the various classes of     
casting-dies4 ,the bearings produced by 
die-casting are so far superior  to     
those made by other casting methods and 
machining that their use is  now very   

extensive4 ,dies are made for           
8half-round0 and 8whole-round0          
bearings4 ,there is little out of the   
ordinary about a whole-round die1  but  
the half-round die involves many        
interesting methods of die-making1  and 
for that reason is here described4      
,fig4 #ac shows a casting-die for       
half-round bearings4 ,half-round bearing
  dies are usually made to cast two     
bearings at a time1 for the reason  that
 it is just as easy to cast two pieces  
of such a shape as it is to  cast one1  
and1 in addition1 the die is balanced in
 a better manner4 ,as  with other dies1 
the first step is to machine up the     
frame ,a and the  two die-halves ,b and 
,c4 ,the pieces ,d and ,e that are to   
form  the insides of the bearings are   
then turned up and one side of each     
shaped and keyed to fit the slots that  
have previously been milled in  die-half
 ,c4 ,these parts are held in place by  
dowels and screws4 ,one  of the bearings
 produced by this die is shown in ,fig4 

#ad1 and it will  be noticed that there 
is an oil groove within that covers the 
length  of the bearing4 ,to produce this
 groove in the die-castings1 a shell    
must be turned up and bored out whose   
inside diameter is that of the  inside  
of the bearing1 and whose thickness     
equals the depth of the oil  groove4    
,this being done1 the oil grooves are   
laid out upon the shell  and cut out by 
drilling and filing4 ,after rounding the
 outside corners1  these little strips  
are pinned to the cores ,d and ,e in    
their proper  places4    ,illustration3 
,fig4 #ad4 ,die-cast ,half-round        
,bearing1 ,showing the ,cast  ,oil      
,grooves    ,another little kink in this
 connection is worthy of noting4 ,so    
many  different styles and sizes of     
bearings are made by a concern doing    
much  die-casting that it is essential  
that the die-cast bearings should  bear 
some distinguishing number to identify  
them4 ,as this number is  of no         
consequence to the user it is well to   

have the number in an  inconspicuous    
place1 but it must be where it will not 
be effaced by  scraping1 etc4 ,bearing  
in mind that it is much easier to       
produce raised  lettering by die-casting
 than to produce sunken lettering1 it   
will be  readily seen that the oil      
groove affords a good place in which to 
put the bearing number4 ,this is easily 
done by stamping the figures  upon the  
narrow strip that forms the oil groove4 
,in this place on the  bearing it may be
 easily found if needed1 and of course  
there is no  danger of its being taken  
out by machining4    ,the lower die     
consists of two blocks ,f and ,g1 each  
of which  contains an impression of a   
bearing4 ,the best way to make these    
parts  is to lay out the ends of each of
 the blocks with the proper radius1     
taking care to have the center come a   
little below the surface of the  face of
 the block4 ,then the blocks should be  
shaped out to get the bulk  of the stock
 out1 before setting up in the lathe4   

,after the lathe work  is done on each  
piece1 which of course is usually done  
separately1 the  faces of the two blocks
 are faced down just to the exact center
 of the  impression4 ,it will be noticed
 that two blocks are used for the lower 
part of the die4 ,the reason is to      
facilitate the locating of the female   
parts of the die in proper relation to  
the male parts4 ,after properly         
locating1 they may be doweled and       
screwed to baseplate ,b4                
,illustration3 ,fig4 #ae4 ,interesting  
,examples of ,die-castings    ,the sprue
 cutter ,h1 better shown in the plan    
view1 is square in shape  and connects  
with the die-cavities in a thin narrow  
opening on either  side of the sprue    
cutter4 ,the ejector pins1 ,i1 two to   
each die1 are  at the ends of the       
bearings4 ,the ejector-pin plate ,j is  
necessarily  large1 and is operated by  
lever ,k4    ,fig4 #ae shows a number of
 interesting examples of die-castings4  
,,chapter ,,iii    ,,van ,,wagner ,,mfg4

 ,,co4',s ,,die-,,casting ,,practice    
,in #aijg1 ,mr4 ,e4 ,b4 ,van ,wagner1 of
 ,syracuse1 ,n4 ,y41 established the    
,e4 ,b4 ,van ,wagner ,mfg4 ,co4 for the 
production of die-castings4 ,the        
factory comprises the office section1   
the machine shop where the dies  and    
casting machines are built1 the         
metallurgical laboratory where the      
metals are alloyed1 the casting         
department shown in ,fig4 #ag where the 
die-castings are made1 and the trimming 
department4      ,possibilities and     
,limitations of ,die ,casting           
,illustration3 ,fig4 #af4 ,die-casting  
,constructions to be avoided    ,at the 
outset we may say that it is possible to
 die-cast almost any  piece1 but it is  
not by any means practicable to do so4  
,it must be  remembered that to die-cast
 on a practical basis the dies must be  
constructed in such a manner that the   
cost of their operation and  up-keep    
will be light1 or there will be no      
profit in die-casting4 ,it  is          

impracticable to produce under-cut work1
 that is1 work having no  draft and     
which is therefore impossible to draw   
from the die4 ,such  an instance is that
 illustrated at ,a1 ,fig4 #af1 and by   
the internal  section of ,m1 ,fig4 #ba1 
and the internal groove in ,o1 also     
shown  in ,fig4 #ba4 ,if absolutely     
necessary1 work of this kind can be done
 by  the use of collapsible cores2 but  
here1 again1 we meet resistance in      
maintaining the dies in proper          
condition1 and1 moreover1 this method   
is commercially impracticable1 owing to 
the difficulty of operating  these cores
 rapidly4 ,hollow work1 requiring curved
 cores1 like faucets  and bent piping of
 the character illustrated at ,c in     
,fig4 #af1 are  difficult to produce4   
,if1 in designing the piece1 it can be  
planned to  have the parts of such a    
shape that the cores can be readily     
withdrawn1  employing a two-piece core  
with a slight draft in each direction1  
the division coming as indicated by the 

core line of ,c in ,fig4 #af1  the      
problem becomes simpler4 ,oftentimes    
this work can best be done  by casting  
in a straight piece1 afterward bending  
the die-casting4  ,it does not pay to   
cast rough heavy work that can be made  
just as  efficiently by sand casting4   
,generally speaking1 the greatest saving
  can be effected by die-casting small  
pieces which have previously  required a
 large amount of machining to produce4  
,on large plain work  the amount of     
metal required for the casting makes the
 cost excessive  on account of the      
difference in cost of the metals4 ,if1  
however1 the  large work must be finely 
finished by polishing1 etc41 it is      
oftentimes  found of advantage to       
die-cast4 ,corners1 especially those    
joining thick  and thin sections1 as at 
,b1 ,fig4 #af1 should be heavily        
filleted  as shown on one side of this  
piece4 ,regarding the casting of thin   
sections1 it is not practicable to try  
to cast sections under #c_/fd  inch in  

thickness1 as the metal runs with       
difficulty into such narrow  places4 ,a 
casting having walls #a_/af inch1 like  
that shown at ,x1 ,fig4  #bd1 is easily 
cast4 ,threaded sections1 if the threads
 are fine1 say1  under twenty-four to   
the inch1 should not be die-cast1       
because under  moderate pressure they   
will strip4 ,a good way to treat        
constructions of  this kind is to       
enclose brass or steel bushings in the  
die-castings in  which the threads are  
required4    ,illustration3 ,fig4 #ag4  
,view of the ,casting ,room    ,as to   
the accuracy with which die-castings may
 be produced1 it is  possible to keep   
dimensions within #j4jjje inch of       
standard size1 but to  do so requires   
considerable expense in keeping the dies
 in condition4  ,a limit of #j4jjb inch1
 however1 is entirely practicable1 and  
can be  maintained easily4 ,in          
specifying the accuracy with which      
die-castings  are to be made1 only those
 parts which are absolutely essential   

should  be held to size1 in order to    
keep the cost of the work nominal4 ,one 
of  the great advantages of the use of  
die-castings is that no finishing is    
required after the pieces leave the     
molds4 ,finish requirements should  be  
plainly stated in ordering die-castings1
 as the alloy must be suited  to these  
requirements4    ,illustration3 ,fig4   
#ah4 ,methods of attaching ,die-cast    
,gears1 etc41 to  ,shafts    ,another   
great saving is effected on lettered    
work1 either raised or  sunken4 ,one of 
these jobs is illustrated at ,q1 ,fig4  
#bb1 which shows  an example of die-cast
 lettering4 ,sunken lettering is to be  
preferred  to raised lettering1 as the  
latter is more easily injured4 ,knurled 
work may be produced easily1 if straight
 knurls are used1 and threaded  sections
 over  inch in size are entirely        
practicable1 either internal  or        
external4 ,external die cast threads are
 illustrated at ,r and ,s1  ,fig4 #bb4  
,the casting of gears and segments is a 

familiar application  of die-casting2   
this is illustrated by the large gear at
 ,n1 ,fig4 #ba1  and the segment at ,w1 
,fig4 #bc1 which give an idea of the    
general  character of this class of     
work4 ,the casting of pulleys1 gears1   
and  similar parts on shafts may be     
easily effected as shown by the gear on 
the shaft at ,n1 in ,fig4 #ba4 ,the     
views shown in ,fig4 #ah are intended   
to convey an idea of three methods of   
die-casting around shafts4 ,at  ,d is   
shown a die-casting cast around a steel 
shaft4 ,if the surface  of the shaft    
coming within the pulley has been       
previously knurled1  the pulley will    
grip it much better1 but for ordinary   
purposes the  shrinkage of the die-cast 
metal around the shaft is sufficient4   
,if any  heavy strain is to be imposed  
on the work1 it is better to provide    
anchor holes through the shaft1 like    
those indicated at ,e4 ,it will be      
readily seen that the die-cast metal    
runs through these holes in the  shaft1 

forming rivets which are integral with  
the casting4 ,for locating  levers upon 
the ends of shafts1 etc41 a good way is 
to flatten opposite  sides of the shaft 
and cast around them1 as shown at ,f1   
,fig4 #ah4 ,the  screw seen projecting  
beneath the piece at ,q1 ,fig4 #bb1 was 
die-cast  in place4 ,any of these       
methods are to be recommended1 and a    
proper  knowledge of possibilities of   
this kind will increase the scope of    
die-casting4    ,illustration3 ,fig4    
#ai4 ,a ,few ,possibilities of ,die     
,casting    ,another phase of           
die-casting which can well be borne in  
mind is the  possibility of inserting   
steel or other parts in the die-casting4
  ,such an instance is shown at ,g in   
,fig4 #ai--;a die-casting which was     
made by the ,van ,wagner ,co4 as a part 
of an electrical apparatus1 the  steel  
inserts being contact points4           
,oftentimes it is found advisable  to   
include brass bearing rings to give     
additional durability at points  where  

the die-cast metal would not stand up4  
,the die-casting shown at  ,u1 ,fig4    
#bc1 in which the brass ring at ,t has  
been incorporated1  is typical of such  
cases4 ,to die-cast pieces like those   
shown at  ,h in ,fig4 #ai1 and similarly
 at ,v in ,fig4 #bc1 having inverted    
conical openings1 might at first thought
 seem difficult1 but this is  entirely  
practicable4 ,similarly1 split bushings 
like those shown at  ,i1 ,fig4 #ai1 and 
at ,w1 ,fig4 #bc1 may be cast with      
projecting lugs  for the reception of   
screws for clamping upon shafts1 etc41  
but this  construction should not be    
used if frequent tightening or loosening
  will be necessary4    ,illustration3  
,fig4 #bj4 ,castings which illustrate   
,points of ,shrinkage  and ,draft       
,illustration3 ,fig4 #ba4 ,die-castings 
showing ,impractical ,under-cut         
,sections2 also a ,large ,gear die-cast 
on ,shaft    ,illustration3 ,fig4 #bb4  
,die-castings which show ,lettering and 
,thread  ,castings    ,the shrinkage    

problem manifests itself in die-casting 
in the same  measure that it does in    
other casting operations4 ,different    
metals  shrink in different degrees1 as 
will be explained later on4 ,however1   
one important point can be mentioned at 
this time3 that is1 the amount  of      
shrinkage is often dependent upon the   
shape of the piece4 ,for  instance1     
pieces like those shown at ,k in ,fig4  
#bj or at ,x in ,fig4  #bd1 will shrink 
very little on account of the fact that 
the steel mold  is of such shape that   
the central core will prevent the       
die-casting  from shrinking4 ,however1  
pieces like those shown at ,l in ,fig4  
#bj1  or at ,v in ,fig4 #bd1 which have 
nothing to hold them from pulling       
together as they cool1 will shrink to   
the greatest extent4 ,all of  these     
points must be taken into consideration 
when designing work for  die-casting4   
,practically no draft is necessary on a 
die-casting1 except  on very deep       
sections1 as indicated at ,j in ,fig4   

#bj1 where a draft  of #j4jja inch to   
the inch is desirable4 ,perfectly       
straight sections1  however1 can be     
cast1 as the shrinkage of the metal is  
usually enough  to free it from the die4
    ,illustration3 ,fig4 #bc4 ,typical  
,die-castings illustrating ,various     
,points    ,illustration3 ,fig4 #bd4    
,die-castings illustrating the ,extremes
 of  ,shrinkage    ,it is the opinion of
 the ,van ,wagner ,co4 that die-casting 
costs can  be materially reduced if     
designers will bear this point in mind  
when  bringing out new designs4 ,even   
though it is often possible to cast     
special pieces1 incorporating several   
parts in one1 and thereby  accomplishing
 what seems to be a great stunt to the  
designer1 it is  sometimes more         
practicable to make the piece in several
 sections and  later assemble it4 ,not  
only is this simpler for the die caster1
 but it  is also more economical for the
 customer4 ,such points as avoiding thin
  sections1 including large fillets at  

corners1 as well as taking account  of  
the under-cut problem1 are simply       
matters of common sense1 but they  can  
profitably be considered by the         
designer4      ,the ,van ,wagner        
,die-casting ,machine    ,the first     
essential to good die-casting is a good 
casting machine4  ,perhaps the best     
known types of casting machines are of  
the familiar  plunger type1 of which    
there are several varieties1 the        
pneumatic type  and the rotary or       
automatic type4 7,for descriptions of   
various types of  die-casting machines1 
see 8,die ,casting ,machines10          
,,machinery',s ,reference  ,book ,no4   
#ajh47 ,for the economical production of
 die-castings1 however1  the            
hand-operated machines are rather too   
slow1 and automatic machines  are       
applicable only to a class of work which
 may be made in very large  quantities4 
,for these reasons1 therefore1 the ,van 
,wagner ,co4 employs  the compressed air
 type of die-casting machine which was  

patented by  ,mr4 ,e4 ,b4 ,van ,wagner  
in #aijg4 ,in the casting department of 
the ,van  ,wagner shop1 illustrated in  
,fig4 #ag1 there are installed about    
thirty  machines4 ,fig4 #bg shows a     
die-casting machine in the open         
position4  ,fig4 #bf shows a closer view
 of the die-operating mechanism and     
,fig4 #be  is presented to give a       
general idea of the construction of the 
entire  machine4    ,illustration3 ,fig4
 #be4 ,drawing illustrating ,principle  
of ,van ,wagner  ,die-casting ,machine  
,by referring to the line illustration  
,fig4 #be1 which shows the ,van  ,wagner
 pneumatic die-casting machine in part1 
and comparing this  illustration with   
,fig4 #bf1 which shows the general      
appearance of the  die-operating and    
other mechanism of the casting machine1 
a good idea  may be obtained of its     
construction and working4 ,at ,a may be 
seen  the base of the machine in which  
is located the melting pot ,b4 ,this    
melting pot is heated by means of fuel  

oil passing through the supply  pipe ,c 
to the burners ,c#a4 ,a vent pipe ,d is 
provided to take  away the gases        
incident to combustion4 ,the pressure   
for 8shooting0 the  metal into the die  
cavity is supplied by air through the   
supply pipe  ,e4 ,a valve controls this 
air supply4 ,the pressure is regulated  
to  suit the particular casting or die1 
the proper amount being determined  by  
experiment4 ,similarly1 an air exhaust  
pipe ,f1 which may be seen  directly    
above the supply pipe1 sub-divides into 
two tubes which  extend to the die      
cavity to exhaust the air before the    
metal is  admitted4 ,there are two      
methods of overcoming the presence of   
air in  the die cavity--the exhaust     
method and the venting method1 and it is
  the former that is here described4    
,illustration3 ,fig4 #bf4 ,view of      
,machine showing ,die-operating         
,mechanism    ,a 8goose-neck0 ,g1 shown 
in ,fig4 #be1 serves to temporarily     
contain  the metal which is forced into 

the mold4 ,an amount of metal slightly  
in excess of that required for one      
die-casting is placed in this           
goose-neck with a hand-ladle1 previous  
to each operation of the  machine4 ,one 
end of the goose-neck is connected to   
the air pipe1 ,e1  while the other end  
terminates in the nozzle ,g#a4 ,this    
nozzle may  best be seen by referring to
 the illustration of the machine shown  
in  ,fig4 #bg1 in connection with ,fig4 
#be4 ,one of the advantages in using    
this goose-neck is that the entire air  
pressure is expended upon the  metal in 
the goose-neck1 and1 by reason of its   
isolated position1 the  goose-neck and  
its contents are kept slightly hotter   
than the contents  of the melting pot4  
,the ,die-operating ,mechanism    ,the  
die-operating mechanism of the machine  
is contained within a hinged  framework1
 shown in position for the removal of   
the die-casting in ,fig4  #bg4          
,referring to ,fig4 #bf1 in connection  
with the line illustration ,fig4  #be1  

it will be seen that the die-holding    
mechanism is all supported  upon the    
lower die-holding plate ,h1 which is    
hinged to the edge  of the base of the  
machine4 ,a lock ,j serves to hold the  
dies and  operating mechanism in the    
upright operating position1 and by means
  of a counterbalance1 suspended from an
 overhead rope which connects  with the 
top of the mechanism at ,p1 the changing
 of the position of  this mechanism is  
easily effected1 and when thrown into   
the horizontal  position1 as indicated  
in ,fig4 #bg1 it rests upon a support   
while the  dies are being opened and the
 castings ejected4    ,illustration3    
,fig4 #bg4 ,die-casting ,machine in     
,position for ,removal of  ,casting     
,the lower die is shown at ,h#a and the 
upper die ,k#a is mounted  upon the     
upper die-holding plate ,k4 ,four rods  
,l act as guiding  members for the upper
 die-holding plate to slide upon4 ,these
 rods ,l  are mounted in fixed positions
 at the corners of the lower die-holding

  plate ,h1 and at their upper ends the 
operating shaft supporting plate  ,m is 
located in a fixed position1 serving to 
support the upper ends  of these rods4  
,the position of this plate ,m is       
adjustable upon the  rods by means of   
check-nuts1 thus providing for the      
accommodation of  thick as well as thin 
dies4 ,a shaft ,o is supported in this  
top plate1  and by means of the         
operating lever ,n working through      
slotted levers  ,o#a and links ,o#b1 the
 upper die-holding plate and die can    
thus  be removed from contact with the  
lower die at will4    ,the metal enters 
the die cavity through the nozzle ,g#a  
and after  setting1 it is necessary to  
cut the sprue formed by the surplus     
metal  that remains outside the die     
cavity4 ,for this purpose1 a            
sprue-cutter1  operated by means of     
hand-lever ,q#a1 is employed4 ,this     
sprue-cutting  lever is hinged in the   
fulcrumed link ,q#b1 and is held in its 
casting position by means of an         

adjustable stop on bracket ,q#c4        
,illustration3 ,fig4 #bh4 ,general ,view
 of ,trimming ,department    ,in many   
dies1 it is necessary that water be     
circulated through the  die-blocks to   
keep them cool during the die-casting   
operation4 ,in  ,fig4 #bf1 the water    
pipe may be seen at ,r1 and hose pipes  
run from  this supply to each side of   
the die-blocks1 thus providing a cooling
  circulation4 ,in this illustration1   
the pipes used for exhausting the  air  
from the die cavity are apt to be       
confused with the cooling pipes1  but by
 following the two pipes leading        
vertically down to the machine1  the    
exhaust pipes may be seen and kept      
distinct from the water pipes4          
,making a ,die-casting    ,in order to  
clearly understand the operation of the 
die-casting  machine1 let us follow the 
sequence of events that takes place in  
producing a casting4 ,two men are       
required to operate the machine4 ,in    
,fig4 #bg1 the operators may be seen in 

their working positions4 ,the  first    
step is taken by the operator at the    
left who1 with a hand-ladle1  dips      
enough metal for one casting from the   
melting pot and pours it  through nozzle
 ,g#a into the goose-neck4 ,the second  
operator in the  meantime is replacing  
the cores in the dies1 adjusting the    
position of  the sprue-cutter and       
closing the dies preparatory to making a
 casting4  ,this being done1 he elevates
 the dies and their operating mechanism1
  which are hinged and counterbalanced1 
as previously described1 bringing  them 
to an upright position4 ,the die        
operator now mounts the box1  raises the
 sprue-cutter to its open position to   
admit the metal2 after  which the       
machine operator turns the air valve    
with his left hand4 ,the  operation of  
this air valve admits the air behind the
 metal1 forcing it  into the die1 and   
the same movement opens the exhaust     
valve slightly in  advance4 ,the exhaust
 valve is located upon the second length

 of piping  just above the air valve1   
and as a link connects the two valves1  
the  single motion exhausts the air from
 the die cavity and immediately         
afterward the air is admitted behind the
 metal1 thereby 8shooting0 the  metal   
into the die4 ,this being done1 the air 
is shut off and the die  operator cuts  
the sprue by means of lever ,q#a1       
withdraws the cores  in the die1 throws 
the dies to the open position 7which is 
indicated  in ,fig4 #bg71 and operates  
the ejecting mechanism1 thus removing   
the  casting from the die4 ,in the      
meantime1 the machine operator is       
tending  to his metal supply and getting
 a ladle full of metal ready for the    
next die-casting operation4 ,by         
referring to the machines shown in ,fig4
  #ag1 it will be noticed that only a   
few are provided with exhaust piping    
for venting the dies4 ,another venting  
method will be described later4         
,illustration3 ,fig4 #bi4 ,trimming     
,die-castings on a ,filing ,machine     

,the number of die-castings which can be
 made on one machine per day of  ten    
hours varies with the character of the  
pieces being die-cast1 the  number of   
pieces made at each operation of the    
machine and the ease  with which the    
dies may be worked1 which depends1 of   
course1 upon the  number of cores and   
parts to be handled at each die-casting 
operation4  ,the dies shown in the      
machine in ,fig4 #bf1 produce four      
bearings at each  operation4            
,trimming ,die-castings    ,at the end  
of each run the operators of the        
machines go over their  work1 breaking  
the castings from the sprues and        
throwing out all that  are defective4   
,no matter how carefully the die-casting
 molds have been  made1 there is always 
a certain amount of trimming to be done 
on the  finished die-castings1 on       
account of the crevices left in the die 
for  air vents1 or which exist from     
improper fitting of the parts of the    
dies4 ,these 8fins10 as they are called1

 are trimmed by hand operators  in a    
special department4 ,a general view of  
this trimming room is shown  in ,fig4   
#bh4 ,usually it is sufficient to scrape
 these fins off with a  scraping knife1 
but if the casting is especially        
difficult to produce1  so that a large  
opening is required to admit the metal1 
it is sometimes  necessary to trim      
unusually thick sprue sections by       
filing4 ,fig4 #bi  illustrates the      
method of trimming such die-castings on 
a filing  machine4    ,illustration3    
,fig4 #cj4 ,general ,view of ,e4 ,b4    
,van ,wagner ,co4's ,die  making        
,department    ,illustration3 ,fig4 #ca4
 ,a ,typical ,die-casting ,mold         
,the ,dies ,used    ,next to the casting
 machine1 the dies or molds are the most
 important  necessary factor4 ,a general
 view of the ,van ,wagner ,co4's        
die-making  department is shown in ,fig4
 #cj4 ,in order to gain a proper        
conception of  the work required in     
producing a high-grade die-casting mold1

 we will  follow the different steps    
which are necessary in making the mold4 
,the  first and most important step is  
the proper planning of the die4 ,before 
any work at all can be done1 it is      
necessary to plan the die1 i4 e41  to   
decide just where the parting lines will
 come2 just what method  will be used   
for ejecting the piece2 what alloy will 
be used2 where  the casting will be     
gated2 and a hundred and one minor      
points1 all of  which have a direct     
bearing upon the performance of the     
finished dies4  ,all these decisions    
have to be made by the diemaker1 and in 
,fig4 #cg he  is shown1 micrometer in   
hand1 computing the shrinkage allowances
 that  he will make in the dies4 ,this  
is a very important factor on accurate  
work as the shrinkage varies from #j4jja
 to #j4jjd inch1 according to the  alloy
 and the general shape of the piece4    
,illustration3 ,fig4 #cb4 ,die-casting  
,mold shown in ,fig4 #ca1 disassembled  
,before taking up the actual machining  

operations of the mold-making  as       
conducted in this factory1 it will be   
well to take a typical  die-casting mold
 and note its general construction4     
,fig4 #ca shows a  typical die-casting  
mold closed1 while ,fig4 #cb shows the  
same mold  disassembled on the bench to 
show its construction4 ,the piece for   
which the mold has been made is also    
shown4 ,fig4 #cc shows a similar  die in
 section4 ,from the three illustrations 
a good idea of an average  die-casting  
mold can be obtained4 ,referring to     
these illustrations1 the  principal     
parts of this die are the ejector box   
,a1 and the ejector  plate ,b which is  
operated by the racks ,c4 ,for operating
 the ejector  plate1 the pinion shaft ,d
 having a handle suitable for turning1  
is  furnished4 ,this1 of course1 fits   
into a bored hole in the ejector box1   
bringing the pinion into mesh with the  
racks for raising the ejector  plate4   
,in the ejector plate are three ejector 
pins ,e for removing  the casting from  

the mold4 ,the ejector pins operate     
through holes ,f4  ,beyond the pinion   
shaft may be seen the casting for which 
this mold  has been made4 ,it will be   
noticed that the top side of the casting
 has  three projecting lugs through     
which are small holes4 ,provision for   
forming this side of the die-casting is 
made in the lower half of the  mold ,g1 
while the upper half of the die-casting 
is taken care of  by the top plate ,h4  
,one of the toggles for operating the   
core pins  through these three lugs is  
shown at ,i4 ,these parts will be       
described  more fully later4 ,the sprue 
cutter is shown in position in the die  
at  ,j4      ,machining the ,die        
,cavities    ,as will be noticed from   
,fig4 #cj1 the machinery in the         
die-making  department is of modern     
design1 for no other class of work      
demands as  good tool equipment and as  
much skill in the making as die-casting 
molds4 ,the die-blocks are made of      
machinery steel4 ,fig4 #cd illustrates  

the first step in making a die-casting  
mold after the die-block has  been      
shaped approximately to size4 ,this     
operation consists in carefully  facing 
off the die surfaces on a               
vertical-spindle grinding machine4      
,this1 of course1 is a quick method of  
surfacing the die-block1 and  it insures
 that the top and bottom surfaces of    
these plates will be  parallel1         
permitting the die-faces to come        
together properly4    ,illustration3    
,fig4 #cc4 ,section through a           
,die-casting ,mold    ,the next step    
consists of laying out the die1 as shown
 in ,fig4 #cf4 ,this  is done in the    
usual manner1 by working on a coppered  
surface1 using  dividers1 scales1 and a 
center punch4 ,when laying out the die1 
the  necessary allowances are made for  
shrinkage and finish1 these points      
having been planned before actual work  
on the die has been started4 ,as  in    
other phases of die-work1 the machining 
operations are performed1  as far as    

possible1 before any hand-work is done4 
,in ,fig4 #ch may be  seen a die-maker  
turning the cavity in a part of the     
die-casting mold4  ,the highest type of 
skilled workmanship is called for on    
this machine  work1 and as may be       
surmised from ,fig4 #ch1 where the      
die-maker is shown  measuring the die   
with a vernier caliper1 the measurements
 must be  exact1 for no grinding        
operations follow the machine work4     
,illustration3 ,fig4 #cd4 ,first step in
 making the ,mold--,grinding  ,surfaces 
of ,blocks    ,illustration3 ,fig4 #ce4 
,a ,milling ,operation on a ,die        
,figs4 #ce and #ci show typical milling 
operations being performed on           
die-casting molds4 ,in ,fig4 #ci the    
diemaker is shown indicating a pin in   
one corner of the mold cavity1          
preparatory to doing additional milling4
  ,the block is held in the usual manner
 by being clamped on the bed of  the    
milling machine1 and after it has been  
properly located under the  cutter head1

 tools are substituted for the indicator
 and the milling  of the cavity is      
completed4 ,fig4 #ce shows one of the   
sections of the  die-casting mold which 
is to be used in producing the casting  
shown at  the right of the work4 ,in    
this case the diemaker is milling the   
recess  for the steel arbor which may be
 seen directly in the foreground4 ,this 
will be fitted in place to provide for  
the forming of the hole in the  side of 
the piece4    ,illustration3 ,fig4 #cf4 
,laying out ,one of the ,mold ,parts    
,illustration3 ,fig4 #cg4 ,planning the 
,die-casting ,mold    ,illustration3    
,fig4 #ch4 ,turning out a ,die-casting  
,mold    ,illustration3 ,fig4 #ci4      
,indicating a ,mold on the ,milling     
,machine    ,fig4 #dj illustrates       
several important points in the making  
of a  die-casting mold4 ,this           
illustration shows the ejector box with 
the  lower half of the mold on it1 the  
ejector plate being held against the    
under side of the die-plate by means of 

the pinion shaft4 ,the operation  being 
done is the drilling of the ejector-pin 
holes4 ,referring back to  ,fig4 #cb1   
which by the way shows the die here     
illustrated disassembled1  the holes    
being drilled are those shown at ,f for 
the reception of the  pins ,e4 ,the     
method employed is to drill the holes   
through the die and  into the ejector   
plate1 afterward reaming all holes to   
size and driving  the pins into position
 in the ejector plate1 while they are   
allowed to  slide freely through the    
die-plate4 ,we will now assume that the 
ejector  box and plate have been        
completed and fitted1 a pinion shaft for
  operating this plate also fitted1 the 
lower and upper dies completed  by the  
machining operations previously         
described1 and all assembled4  ,the     
final operation of the fitting of the   
pins is shown in ,fig4 #da in  which the
 die-maker may be seen filing off the   
ends of these pins so  that when dropped
 to the lower position they will lie    

flush with the  surface4 ,if of uneven  
lengths1 these pins will cause irregular
 spots in  the casting4 ,it now remains 
to describe the toggles used for        
operating  the cores which form the     
holes through the three lugs in the     
casting4  ,one of these toggles1 of     
which there are three1 is shown at ,i1  
in  ,fig4 #ca1 and also in ,fig4 #cb4   
,these toggles consist of brackets which
  are attached to the die-plate1 and    
levers which are fulcrumed at the  ends 
of the brackets so that their operation 
works the core pins4 ,it is  necessary  
to remove these core pins after each    
casting has been made  and position them
 before another casting can be produced4
    ,illustration3 ,fig4 #dj4 ,drilling 
the ,ejector-pin ,holes    ,the fitting 
of the parts of a die-casting mold is   
one of the  most important parts of the 
work4 ,it demands the highest type of   
workmanship1 for a poorly fitted die    
means a die which works hard  in        
addition to producing poor castings4 ,it

 is very important that  all movable    
parts should work freely4 ,fig4 #db     
shows the assembling  operation on a    
die-casting mold1 the casting which is  
to be duplicated  being shown in the    
immediate foreground4 ,these parts must 
all be  screwed into their respective   
places1 making the joints as nearly     
air-tight as possible4 ,one cause of    
poor die-castings arises from the       
trapping of air in the die1 and         
different methods are employed for      
overcoming this trouble4      ,venting  
the ,dies    ,there are two methods of  
preventing air from being trapped in    
die-casting molds2 either by            
constructing the dies so that the air   
may be exhausted from the mold cavity   
before admitting the metal1 or  by      
venting the die so that the air may be  
forced out by the inrushing  metal4 ,in 
the first of these methods it is        
necessary that the joints in  the mold  
be made as close as possible1 otherwise 
it will be impossible  to produce       

anything like a vacuum in the mold      
cavity4 ,if1 however1 it  has many parts
 which must be fitted1 it is usually    
considered advisable  to provide the die
 with vents consisting of milled        
recesses a few  thousandths inch deep4  
,several vents are provided1 from which 
the air  can escape when the metal is   
admitted to the dies4 ,the hot metal1 of
  course1 8shoots0 through them in thin 
ribbons1 but not enough escapes  to     
affect the pressure on the metal which  
goes into the casting4    ,illustration3
 ,fig4 #da4 ,fitting ,ejector-pins      
,no matter how carefully a die may have 
been constructed1 or how  carefully it  
has been assembled1 there is always a   
certain amount of  8babying0 to be done 
before it will work satisfactorily4 ,the
 casting  may stick a little here1 or   
there may be a rough spot there1 and it 
is the successful elimination of these  
troubles which constitutes the          
production of a good die-casting4       
,die-casting ,metals    ,one of the     

purposes of this book is to correct     
several erroneous  impressions which are
 prevalent in regard to die-casting     
possibilities4  ,many people seem to    
think that nearly all metals can be     
die-cast1 but  as a matter of fact1     
those metals which can be successfully  
die-cast  can be numbered on the fingers
 of one hand1 being alloys of lead1     
zinc1  tin1 copper and antimony4 ,the   
tin base metals shrink very little1     
while  the zinc base metals shrink      
considerably1 and those with a large per
  cent of aluminum have a very high     
shrinkage4 ,without doubt1 the most     
used die-casting metals are the zinc    
base metals4 ,a typical metal of  this  
class contains about #he per cent zinc2 
#h per cent tin2 #d per  cent copper and
 #c per cent aluminum4 ,the melting     
point of this metal  is about #hej      
degrees ,f4 ,while this alloy is one of 
the most common1  it is not by any means
 the best1 as there is too little tin   
employed1  but it is a comparatively    

cheap metal1 which probably accounts for
 its  large use4 ,this metal is easily  
affected by heat and cold1 and rapidly  
deteriorates with age4 ,the lead base   
metals may be typified by an alloy      
containing #hj per cent lead2 #ae per   
cent antimony2 #d per cent tin2 and  #a 
per cent copper4 ,this composition melts
 at approximately #eej degrees  ,f4 and 
is used for castings subjected to little
 wear and where no  great strength is   
required4 ,the weight of this metal is  
its greatest  objection1 and it is also 
quite brittle because of the large      
percentage  of antimony4                
,illustration3 ,fig4 #db4 ,assembling a 
,die-casting ,mold    ,for the best     
class of die-castings1 the tin base     
metals are employed4  ,these range from 
#fj to #ij per cent tin1 and from #b to 
#aj per cent  copper1 together with a   
little antimony4 ,the melting point of a
  mixture of this composition is about  
#fge degrees ,f4 ,the castings have  a  
good color and they are much better in  

quality than any of the other  alloys4  
,it is absolutely essential that tin    
base metals be used for  carbureter     
parts or other parts coming in contact  
with gasoline4 ,also1  the tin base     
metals must be used for parts which come
 in contact with  food products1 as the 
lead or zinc alloys have a contaminating
 effect4    ,aluminum alloys have been  
cast in ,france and ,germany in limited 
quantities1 but very seldom in this     
country on account of their high        
melting point1 as well as their effect  
upon the die4 ,after aluminum  alloys   
have been run in the dies for a short   
time1 the surfaces of the  molds become 
pitted4 ,through some unexplained cause1
 the metal seems  to flake out particles
 of the steel in the molds4 ,when an    
aluminum  alloy is to be used1 a good   
mixture is #hj per cent aluminum1 #c per
 cent  copper and #ag per cent zinc4    
,this alloy has a high shrinkage and it 
has  also the same deteriorating effect 
upon the dies1 but to a much less       

degree than pure aluminum4              
,transcriber's ,notes      ,punctuation1
 hyphenation1 and spelling were made    
consistent when a  predominant          
preference was found in this book2      
otherwise they were not  changed4       
,simple typographical errors were       
corrected2 occasional unbalanced        
quotation marks retained4    ,ambiguous 
hyphens at the ends of lines were       
retained4    ,text uses 8die-cavity0 and
 8die cavity01 8die-maker0 and 8die     
maker02  none changed here4