Quote Originally Posted by routercnc View Post
Hang on. Is this any different to how I have been running this machine for several years? I have 2 identical stepper motors wired the same way to identical stepper drivers. They have their own step/dir signals but as these are slaved they should be the same. When I first built it I aligned the motors to full step with loose couplings and have not touched it since. Z axis sounds smooth as the day it was built. Only difference with the update is running off the same dir and step outputs.
If you haven't been homing each motor then Yes, it's exactly the same. I can't see how the motors won't have jumped in opposite directions at some point and if you haven't got reference marks to check against then it could be very hard to see. It would be a random occurrence and you could have just been lucky that it's not twisted up enough to show up.? Still, it wouldn't be my first choice if I'm honest.!