90 ton 1/14 metal excavator scratch build w/embedded PC

[SteinHDan]

The drive motor drives the drive sprocket directly. A 12mm steel tube (inner diameter 8mm) matches the inner diameter of the drive sprocket and also extends the gear motor axle somewhat.



The gear motor is a very common GW31ZY 12V 14RPM 30Kg/cm. The drive sprocket is an industry standard 08B 16 teeth sprocket. The plastic part is just a part I used for finding the correct distance when drilling the holes. On this drive sprocket it currently serves to hold the pin (a M4 bolt cut to size) in place. On the other sprocket I opted to place the hole inside the sprocket and thus no extra part is needed to keep it in place.

Ebay links for the parts:
- Drive sprocket: http://www.ebay.com/itm/321308379034
- Gearmotor: http://www.ebay.com/itm/291536954105
- Gearmotor alt.: http://www.ebay.com/itm/301680855441