20T Stepper Drive Pinion
A 20-tooth involute spur pinion for the 'NEMA17 Geared Radar Scan Turret' kit. It has module 1.5, a 20° pressure angle, a 30 mm pitch diameter, a 33 mm OD, an 8 mm face and 0.5 mm chamfered tooth tips. It drives the 60T ring gear 3:1 at a 60.25 mm centre distance. It fits the NEMA 17 5 mm shaft through a 5.25 mm bore. The 18 mm hub holds an M3 set screw and a captured M3 hex nut, and the screw bears on the shaft flat.
mechanism kit gear nema17