i had the dreaded Y stepper motor shaft snap off, it was not from over tight belt as i use whitr belts and that can not be used over tightened! there has to be a defect in the shaft design and the pressure from the belt is trying to twist the shaft and makes the defect fail, so i came up with this motor shaft strain relief bracket which has a bearing from a v slot wheel that locks the end of the motor shaft and stops it from twisting from belt pressure so if anything it will make the motor last longer if it has got a faulty shaft, i also came up with a bottom plate that snaps onto the bottom of the stock motor mount just to make sure it stays at 90 degrees, this is for a ender 3 pro which uses the 4040 extrusion, bit will be uploading the 4020 version when i get time.
the bracket also has a fixing hole for an idler pulley to below the exciting top idler pulley, its to put a little more mass on the motor pulley that the top one takes away.
use m4 12mm long bolt and t nut to secure to the extrusion
| stock_Y_stepper_motor_stiffener_plate.stl | 2.4KB | |
| Y_stepper_strain_relief_bracket.stl | 161.0KB |
