Loose pinions

[Acmeaviator]

I have a recurring problem with the Y-axis pinion on my buddy (the one that moves the Z-car along the beam) coming loose. It's a pretty simple fix to unbolt the motor and tighten it but even with a lot of threadlock it loosens again. The other pinions seem to be ok so far - anyone else have this problem or a suggestion for a better solution?

[Brady Watson]

Replace the pinion and crank it down until the wrench wants to bend in your hand. Your current grub screws are probably lose in their bores and can't tighten down as well as a new pinion.

-B