[JensR]

I think that converted servos are really useful and they are basically nothing else than gear motors in a different form factor and packaging anyway?
As long as their gear ratio matches the application - if not then gear motors usually offer a wider range of gear ratios.

I'd love to buy a gear motor with comparable power and double ball bearings that does not cost an arm and a leg. I'd be honestly interested, as I couldn't find one and went with the popular RB35. But these motors only have bushings and these do not take radial loads well, in my experience.

Looks like a great project and the drawings Steve posted are fantastic!