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BELL SYSTEM TECHNICAL JOURNAL 



method, the first appHcation of which was made on the 1818-pair 26 

 B. & S. gauge cableJ 



The unit method consists of two distinct steps. A flier strander is 

 used to strand pairs into individual color groups known as units, which 

 usually consist of 50, 51, or 101 pairs. A cabling machine then 

 assembles a definite number of these units into a round core form. 

 Thus the final cable size is some multiple of 50, 51, or 101 pairs. An 

 1818-pair cable built in this manner is shown in Fig. 12. 



Fig. 13 — Flier strander. 



The flier strander shown in Fig. 13 consists of a reel carriage or drum 

 for holding 101 supply reels of paired wire; a cotton serving head for 

 winding a cotton thread about the unit; a flier for stranding the unit; 

 a pulling mechanism or capstan for advancing the unit through the 

 machine; and a take-up for reeling the finished unit on a core truck. 



By revolving the flier about the normally stationary supply it is 

 possible to obtain two twists in the unit per flier revolution. This 

 combined with the low inertia of the flier permits units to be stranded 

 at the rate of 300 ft. per min. 



The cabling machine shown in Fig. 14 consists of 18 supply stands 

 equipped with suitable pneumatic brakes for holding and maintaining 

 tensions on the trucks of units, and a rotating capstan take-up. The 

 units are pulled through a distributer plate and covered with a pro- 

 tective wrap of paper. A twist is put in the cable between the dis- 



'' Bell Telephone Quarterly, January 1929, " 1800-pair Cable Becomes a Bell 

 System Standard," by F. L. Rhodes. 



