I have an on-going problem with my TAZ 4 (upgraded to a TAZ 5). After every print, the right z-axis stepper motor always has moved up a little more than the left motor.
I recently completed several prints that are 235 mm tall and the error with the right side z-axis appears to be consistent (about 5 mm) for those prints. The issue is similar whether I use ABS or PLA.
I have to disable the steppers and then manually turn the motor to bring the right side back down to match the left side and at that point I can re-zero (AUTO HOME) and everything is fine.
It only get out of alignment when printing. If I use the control panel to manually move the z-axis in 10 cm step from 0 to 240 mm and back down to 0, both sides remain in alignment. But when I print, especially for tall prints, the right side moves up noticeably more than the left. For short prints, the right side z-axis stepper still moves up more than the left but not as much.
TAZ 5 v18.104.22.168, single extruder
I’d start with something simple to rule out a few things - just swap the left and right z-motor plugs at the control board.
Is the problem that the left side isn’t coming up enough, or the right is moving too much? It’s more likely that the left side isn’t moving enough, but by swapping the plugs at the control board, you’ll see whether it’s on the board side, or the motor/mechanical side. If the behavior is the same when swapping Z motor plugs at the control board, check the motor, it may be aging and not responding when there’s power draw from the extruder motor, Y and X axis motors, the heater and heated bed all going at once.
If the problem swaps sides, it could be a failing driver (probably the most likely issue) or the power supply may not be giving enough power anymore, and that’s just the driver that isn’t getting what it needs.
I believe the problem is with the right side coming up too much. I say this because I have to manually rotate the right side z-stepper in order to successfully zero (AUTO HOME) the nozzle. No adjustment is needed for the left side z-stepper. Thanks for the suggestion - I will swap the motor plugs and run a new print to see if I can isolate the problem.
I was able to swap the cables on the MLB for the two z-axis steppers. I verified both steppers are working and I have started a new print. The print will take about 48 hrs. to complete. Assuming no other issues, I will report the results when it finishes.
48 hours is a long time for a test print. If it were me, I’d do something vase mode if it is height you need, but good luck.
My test print still has a few more hrs. but it looks like the right side z-stepper is still moving up more than the left side z-axis stepper even after I swapped the motor connectors. So I assume this indicates the root cause is the z-stepper-motor and/or motor cabling.
It would seem to me that if a 48 hour test print is showing visible signs of uneven stepper movement right to left then the test print is ruined and could be stopped.
I would suspect the stepper motor more than the motor cabling (as long as the cable is firmly connected).
thanks b-morgan. And thanks to Wrathernaut for the tip about vase mode. I had never heard of vase mode before. I looked it up and I see Cura supports it as ‘Spiraled Outer Counter’. It looks very cool and I will try that after I replace my stepper motor.
All I will say after reading your first post, as manual works fine but the micro stepping that is used more during printing gets dropped sometimes. You probably have a mechanical alignment issue on the axis.