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BELL SYSTEM TECHNICAL JOURNAL 



portion of the part is bent up, two complete parts being made with each 

 stroke of the press. The location of the forming section with respect to 

 the blanking section in this tool must be very accurate, as otherwise the 

 blank will not register exactly under the forming punch and an incor- 

 rectly formed part will result. Also, the forming punches must be lo- 

 cated accurately so they will center in the die openings. Other features 



Fig. 14 — Boring datum holes in master plate on veneer milling machine 



regarding the workmanship required on this tool are included in the 

 description of its construction given in the following paragraphs. Stock 

 is fed to the punch and die by an automatic roll feed with an adjustment 

 provided such that a precision feed within ± .0005 in. of the nominal 

 may be obtained, which insures each part being located in the proper 

 position for forming. 



