Hypocycloid gear box 42:1

Green rose Hypocycloid :)
The eccentricity 1.2 (smooth), better if made from iron
Rate reduction: (ratio) 1:42 (2 stages: 1:7 and 1:6)

You need:
1 Bearing 625zz for out put
1 Bearing 607DDU (RBI) for Cam (out size 19mm, hole 6,7mm)
M3x4 bolts for motor
M4x4 bolts for mount
1 Bolt M5 make shaft out put
Some washers more less 1mm
Dimensions: 42x42x24,5mm