Belt transmission with 688 2RS bearings

Last crawled date: 4 years, 4 months ago

WARNING: length of transmission is not the same as the original. It is some 10mm longer, so If you have a truck bed, expect to modify it to fit the transmission.
I decided to go with 4x 688 2RS bearings and 8mm shafts. There are now 2 spacers instead of 4 and they need not bridge the 8mm shaft to old 10mm bearing gap.
Much easier to assemble.
Experiment with 110 or 112 belts, depending on print accuracy. Remember that too tight belts means too much current and thus risk of overheating the motor.
EDIT: added closed bearing holder and closed mid-shaft bearing orifice. Added drawing for both shafts.
You will need:
2x 110 tooth 2GT belt
2x 112 tooth 2GT belt
2x 20 tooth 2GT pulley with 8mm bore, 6mm width
2x 40 tooth 2GT pulley with 8mm bore, 6mm width
2x 8mm metal shaft
4x 688 bearings
EDIT: added *.stl for shafts for reference, added a square interface output shaft that can use u-joints from MrCrankyface original design. But if possible just file down some metal shafts, as I am not sure how durable plastic ones are.