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BELL SYSTEM TECHNICAL JOURNAL 



sense of touch) against the front side of the central opening of the 

 stationary plate, three blocks being shown in this position at A. The 

 disc carries them into the spiral slot at B and while they are passing the 

 front opening in the top plate at C they are given a visual inspection. 



0.0032 



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During the second round they are turned over by the action of the two 

 V grooves in the rotating disc and the radial motion given them by the 

 spiral slot, and the front face is turned up for visual inspection during 

 the second passage across the front opening at D. Any with visible 

 defects are picked off by hand, while the others passing on through 

 the last turn of the spiral at E are fed into the machine (Fig. 10) for 

 the following gaging operations : 



1. 15 lb. weight test for defective cementing. 



2. 5 lb. weight test to detect misplaced inserts. 



3. Gage height of back face of insert — minimum 0.046 in. 



4. Gage thickness of block — maximum 0.220 in. 



5. Gage thickness of block — minimum 0.205 in. 



6. Gage the underflush dimension of insert which must be maximum 



0.0032 in., minimum 0.0024 in., for at least half the area of the 

 face of the carbon insert. 



7. Gage the underflush dimension for minimum 0.0024 in. over entire 



face of insert. 



