1106 THE BELL SYSTEM TECHNICAL JOURNAL, SEPTEMBER 1953 



flyer rotates about an extension of the reel axis and is lightly restrained 

 with a friction drag-brake which prevents flyer overrun and puts just 

 enough tension in the lead-off wire to keep it from flying wild and 

 tangling. The nature of the over end pay-off causes too wide a change 

 in tension as the supply reel is depleted so the flyer braking force is 

 limited and an auxiliary brake sheave is used to supply most of the 

 back-drag on the wire and create a more stable and uniform approach 

 tension to the machine. From this sheave the wire passes through guide 

 tubes to a fanning section which arranges the wires in proper order and 

 guides them to the supply capstan on the mezzanine at the entrance to 

 the plating line (Fig. 2). The supply capstan is of large diameter and 

 strongly electromagnetic and the wire is snubbed to a 140-degree wrap on 

 it to minimize wire slip and creep. The supply end capstan is the speed 

 governor for the entire machine. It is positively driven with a shunt- 

 wound dc motor regulated to hold capstan speed within 3^ of 1 per cent 

 over the adjustable wire speed range of 80 to 120 f.p.m. (Fig. 3). 



The twenty-five wires of each machine are carried through the plating 

 line in spaced relationship by passing alternately over and under a series 



Fig. 2 — String-up of the twenty-five channels of wire carries them from 

 supply spools^ left, through guides and sheaves to the mezzanine location of 

 plating operations. 



