[WileyB-J]

Originally Posted by Shu

I was standing next to the students as they were assembling the boxes and watching every step to make sure they were doing it right. I have previous experience with the standard toughbox and never ran into a problem like this. We took them apart several times to make sure everything was exactly as in the instructions. The only modification we made was to use the hex output shaft and hex bearing in place of the standard configuration.

Can you post pictures?

My guess:

• The cim motor isn't fully seated. (making the pinion mounted on a slight angle)
• Or that a spur gear is mounted backwards. (that the non-lipped side isn't facing a bearing race binding the gear to the transmission case)