repeat drive mini mk2 battle hardening
After running the Repeat Drive Mini - Mk2 for the 2022 MRCA Finals event I am pretty impressed with the durability of the drive system. They sustained quite a few large hits without any permanent damage. That being said, there are some issues that will need to be addressed before their next event.
issues to address
- No thread locker on fasteners from factory
- Motor wires are weakly attached to base of motor
- Motor shaft circlip is inadequate for holding the motor can in place
thread locker
There was no thread locker on any of the gearbox fasteners. The motor mounting plate was loose on all the gearboxes that saw use. I applied Loctite 234 to the screws and reinstalled.
battle harden wires
The small single strand motor wires scare me. These motors are quite small and my hands are quite large. There was a small amount of potting compound holding the wires to the base of the motor, but this quickly became dislodged. To add some strain relief to the motors I am going to apply some cyanoacrylate glue (super glue) and baking soda to wires at the base of the motor.
motor shaft spacer
A small 3d printed part should be able to act as a spacer between the pinion and the motor bearing. This will prevent the can from becoming dislodged again without adding to much complexity or weight. The spacer was printed out of TPU, hopefully it will be hard enough while still allowing for some shock absorption.