Driving floating end (ballscrew)

[routercnc]

I guess you could always loosen and re-tighten the grub screws between the coupler and the ballscrew twice a year to take out any stress. Or you could mount the stepper on a sliding arrangement so that rotations were prevented but it could slide back and forth 0.5mm or so.

[Jonathan]

Or you could mount the stepper on a sliding arrangement so that rotations were prevented but it could slide back and forth 0.5mm or so.

Maybe put a rubber O-ring on each of the 4 bolts that mount the stepper motor. I did that on my rotary table to compensate for a little radial misalignment and it works fine.
It could also damp vibrations...

[John S]

Maybe put a rubber O-ring on each of the 4 bolts that mount the stepper motor. I did that on my rotary table to compensate for a little radial misalignment and it works fine.
It could also damp vibrations...

Oldham couplings were designed to take out radial misalignment, Those lovejoy couplings are a total waste of time and space for CNC machines, they are better off driving sewerage pumps.

[Jonathan]

Oldham couplings were designed to take out radial misalignment...

Yes I know...didn't have time to make an Oldham coupling at the time for the rotary table and haven't bothered since because it works fine. It's only a very very slight misalignment.