[acondit]

Has anyone had any success in replacing the bearings in a stepper motor?

I have several PacSci PowerMaxII P21, P22, M21 and M22 steppers. They all run. But some of them cut out at much lower speeds than the others. They use 6200Z series bearings (readily available). Is it feasible to replace the bearings and see if that makes a difference?

What cautions? What steps?

Thanks,
Alan

[salzburg]

When you change bearings on a perm. magnet motor I think you have

to do it without removing the armature, otherwise you weaken the

perm. magnets.

[acondit]

I have taken another permanent magnet motor apart and put it back together again (and got it to run). Luckily its end plates had machined insets to position the body and of course the end bearings position the rotor. I just don't know whether the steppers are so machined or whether the factory has some kind of special jigs to hold everything when they are putting it together.

I have heard the tale about the magnets losing their power when removed from the field, I don't know whether that is urban legend or true. It really doesn't seem logical to me but I sure can't claim to know that it is untrue. My suspicion would be that it relates more to not getting it back together centered properly. As a former science teacher, I may just have to sacrifice one stepper as an experiment.

Alan