There are three part designs here. Each might be useful on its own.
The Motor Bracket is my first 3d design (yay me!). It requires some minor sanding to get things to fit. Need to learn to not call things so tight.
There is a coupler for a stepper motor to a 5/16 threaded rod. The rod end needs to be tapped since it has no threads (my modeling skills are up to making threads yet). This is destined for my telescope mount.
The pillow blocks hold skate board bearings. The fit for the bearings is a little lose but the nuts hold everything in place so all is good ;-).
The motor coupler was printed lying down to give the best strength when the motor is driving, though the torque here is very low.
The tricky bit is the friction fit on the stepper motor shaft. Learned to use an octagonal profile to allow the shaft to fit without requiring exact tolerances. Anyway, even simple objects teach you things when you are starting.