434 THE BELL SYSTEM TECHNICAL JOURNAL, APRIL 1951 



leads rest on the edges of the strips. The application of a slight pressure by 

 a heated shoe imbeds in one operation the terminal leads of all the compo- 

 nents of the assembly into the plastic material. The machine used for this 

 purpose is shown in Fig. 11. Simultaneously with this operation, the terminal 

 leads extending over the edges of the strips are sheared off to a length suit- 

 able to form terminals to which connections are made. If a component needs 



Fig. 11 — Operator preparing to feed assembly jig to machine where heated shoe im- 

 beds terminal leads of components into the thermoplastic strips. Cuttings from sheared 

 off terminal leads may be seen below machine. 



to be replaced this is readily done by applying heat to its leads with a solder- 

 ing iron. To facilitate making the relatively large number of wiring connec- 

 t'ons to the pigtail components as well as to terminals of other components, 

 pistol wrapped connections are used in many cases rather than the wrapping 

 by hand with a pair of pliers. The electrically operated wiring pistol illus- 

 trated in Fig. 12 wraps the wire onto the terminal with high tension. The 

 connections are then soldered. 



