Hi there. I’m putting the finishing touches on my ROV, and I went to work on it yesterday and discovered that the port motor mounting bracket had cracked just inside the front mounting screw hole on the side closest to the motor. I’m fairly certain it cracked under just the weight of the motor. The screw did not appear particularly over tight, and I’m pretty sure no one else hit the motor or knocked it around any. I’d just buy another bracket if they were available in the store, but they aren’t.
You might want to consider some structure changes to future production runs. I’d probably just make the last 4-6 hollow sections under the mounting hole on either end solid, thicken the narrowest section by another 2mm, and maybe add provision for 2 mounting holes at either end to allow for mount redundancy.
I dunno, maybe I just got a bad casting.