The No, 516 Hypoid Lapper is designed primarily for lapping automotive and truck spi­ral bevel and hypoid gears and pinions operat­ing at a 90" shaft angle with gear diameters up to 24" (609.6 mm). The No. 516 Hypoid tapper affords fast lap­ping times, high quality, accurate control and great flexibility, Most important is Swing Pinion Cone (SPC} lapping action which, combined with the conventional pinion horizontal and backlash motions, permits fast accurate lap• ping of the tooth surface. This SPC tapping method produces pinions and gears precisely mated to operate in auto­motive and truck drive axles under the ever changing high way driving conditions with max­imum smoothness and quietness.