if your motorising the dob.. more than likely u'll be friction driving it.. and this even applies to gear/worm driving it to some extent, but there will always be a bit of play.. alot more if friction driving i would've though. You wouldn't run like the stepper to run 10 revolutions clockwise.. and expect it to be at the spot, because more than likely it wouldn't driving something that size. So you'd run turn motor clockwise unti encoder reaches the spot and you're there... spot on.. no play.. no leeway.. well as long as u'r encoder was fitted properly
el
