Standardizing the Die-Sinker 



An automatic machine which can produce fifteen 

 dies in the time formerly required to make one 



By Herbert F. Sherwood 



WHEN you have four hundred drop 

 forgers to keep busy and wish to 

 turn out from 200,000 to 250,000 

 forgings in the course of every twenty-four 

 hours* you begin to take thought as to 

 how you can save in the necessary opera- 

 tions. Do any pieces require three different 

 manipulations when two will answer ? Are 

 there any machines, or can any be invented 

 to reduce hand work? 



One of the necessary details of making 

 drop forgings, of course, is that of producing 

 the dies. The pattern's the thing. It 

 must be exactly right, cut to the one- 

 thousandth part of an inch of the desired 

 dimensions. In making rifles the 

 dies must fit so closely together 

 when the hammer comes 

 down that the "flash" — 

 in other words, the 

 excess metal which 

 spreads out around 

 the forging between 

 the two dies, will be 

 like paper for thin- 

 ness. The thinner 

 the flash, within 

 reason, the greater 

 the production from 

 the trimming presses 

 which later cut off 

 the halo of metal. 



In a Bridgeport, 

 Conn., plant a way 

 has been worked out 

 not only of standard- 

 izing the process of 

 making dies to serve as models, but of 

 adapting the principle used in copying 

 statues and making jewelers' dies by ma- 

 chinery, to the sinking of larger dies. In 

 the making of a standardized article, such 

 as a bayonet, however, and where consider- 

 able numbers of large dies are required, it 

 has been demonstrated that it is practicable 

 and economical to plan out in advance the 

 different operations required in the making 

 of a given die and specify them on a card 

 of directions accompanying the block of 

 metal from which the die is to be made. 

 The outline of the desired die is drawn 

 upon the coppered surface of the block 



SPRING PENCIL-LIKE 



STYLUS COMPLETED 

 MODEL 



By means of this machine one die 

 can be made in eight hours. One 

 man can supervise three machines 



and the directions specify what cuts shall 

 be made, and the exact depths which shall 

 be given to them. The cutting tools that 

 shall be used are also named. One work- 

 man may not necessarily perform all of 

 ■the work. Some of it may not require 

 an expert's attention. 



The model completed, it is put into a 

 machine which carries also an uncut block. 

 This machine is equipped with two arms 

 connected so that they will work like a 

 pantograph. At the end of one of these 

 arms is a pencil-like stylus of metal whose 

 point, pressed against the model, follows 

 every indentation in and out. To the 

 other arm is attached 

 another stylus, also 

 about the diameter and 

 shape of a carefully 

 sharpened pencil. This 

 one, made of very hard 

 steel, revolves so rap- 

 idly and smoothly that 

 its cutting edges can- 

 not be seen. As the 

 upper stylus moves up 

 and down across the 

 face of the model in 

 parallel vertical lines 

 five one-thousandths 

 of an inch apart, the 

 fast flying pencil-like 

 stylus below follows 

 suit across the uncut 

 surface of the lower 

 block. With the 

 same undeviating 

 evenness of speed that characterizes the 

 movement of the earth around the sun, 

 it engraves a reproduction of the model. 



Ordinarily, by the old methods it would 

 require one man's time for from thirty-six 

 to forty hours to produce the die. By 

 means of this machine, the same work 

 can be done in eight hours, and one man 

 can supervise three machines. In this 

 way fifteen dies can be produced by him 

 in the same length of time which was 

 formerly required for one. Owing to the 

 more automatic character of the work, 

 a less experienced man can be employed for 

 this part of the operation at less cost. 



440 



