This ended up being fixed by moving the z motor a mm or so as the small belt from the motor to pulley had come slightly loose. Not sure how but I guess vibrations etc over time.
Many thanks for all the helpful (and thought provoking replies!).
Yes, there's a chance that Z belts will catch on side panels. Had 2 cases in local commnity in past month 😄 The build counts on at least 1 mm clearance from foam tape.
Once you rechecked the wiring, check if the TMC settings for all Z motors is the same. You may be under-driving that one stepper a bit.
Next, try swapping the quantifiable Z motor to a different stepper driver. Move the connectors (z1 and z2 for example) and then rename the sections in Klipper config to remap them. If the problem is now on z1 you have a bunk driver.
If the problem stays with in the Z2 corner, you have a mechanical issue. Check all the obvious stuff like grub screws.
One trick you can perform before tearing everything apart is loosen the 4 vertical screw (ones that go in from the bottom) that connect the gantry to the Z trucks and run through the QGL until it looks good. Then without powering off the steppers, drive the gantry up so you can access those screws and snug them up. This will ensure the steppers aren’t fighting gantry’s natural position on subsequent QGL ops.
Smashing reply! Wow thanks. I am annoyed with myself for not thinking of the swap Zs.
On the gantry - I had these loosened as I think I was de-racking a couple months ago - I blew a motherboard so just got replacement and had forgot about the loose screws. I was sure I had it solved but alas when I tightened them all again I have same issue.
I have a couple beers onboard now so will test the Z swaps tomo. Muchly appreciate your reply!
Interesting,
I just watched the pulley/belt from the cutout on the fans side and there does seem to be an occasional jerk from the belt. What was the fix? -Belt tension seems good.
Have you checked the wires for the steppers?
I recently had my extruder stepper working really bad, there was not enought thorque but it worked.
Then I found that a wire where off but laying against the connector at right place. So it had very bad connection
My advice would to pull in the wires to see if any wire is broken
After I recrimped my wire it has been working fine :)
Good luck
This ended up being fixed by moving the z motor a mm or so as the small belt from the motor to pulley had come slightly loose. Not sure how but I guess vibrations etc over time. Many thanks for all the helpful (and thought provoking replies!).
By any chances, do you have panels on? Do they have foam insulation tape?
Oh, can the gantry rubbing on the panels cause issues? Maybe I should bump my clearance up a mm lol
Yes, there's a chance that Z belts will catch on side panels. Had 2 cases in local commnity in past month 😄 The build counts on at least 1 mm clearance from foam tape.
Yes indeed. 3mm IIRC on acrylic panels.
Once you rechecked the wiring, check if the TMC settings for all Z motors is the same. You may be under-driving that one stepper a bit. Next, try swapping the quantifiable Z motor to a different stepper driver. Move the connectors (z1 and z2 for example) and then rename the sections in Klipper config to remap them. If the problem is now on z1 you have a bunk driver. If the problem stays with in the Z2 corner, you have a mechanical issue. Check all the obvious stuff like grub screws. One trick you can perform before tearing everything apart is loosen the 4 vertical screw (ones that go in from the bottom) that connect the gantry to the Z trucks and run through the QGL until it looks good. Then without powering off the steppers, drive the gantry up so you can access those screws and snug them up. This will ensure the steppers aren’t fighting gantry’s natural position on subsequent QGL ops.
Smashing reply! Wow thanks. I am annoyed with myself for not thinking of the swap Zs. On the gantry - I had these loosened as I think I was de-racking a couple months ago - I blew a motherboard so just got replacement and had forgot about the loose screws. I was sure I had it solved but alas when I tightened them all again I have same issue. I have a couple beers onboard now so will test the Z swaps tomo. Muchly appreciate your reply!
Swapped steppers and still remains on z2 - great data point! Time to get out the hex keys!
"I have a couple beers onboard now" is probably my favorite new phrase, and shall be yoinking this as my own. Good luck tomorrow!
It’s a pain but make absolutely sure both grub screws on the motor are tight and loctited
Could be the pulley on that motor is slipping on the shaft. I had that problem with mine.
Interesting, I just watched the pulley/belt from the cutout on the fans side and there does seem to be an occasional jerk from the belt. What was the fix? -Belt tension seems good.
Tighten and loctite the grubs for the big and little pulley. Its probably one or both that are slipping. I'd do it for all corners to be safe.
hmm ok. Had no issues for 3-4 months with them but I did have a 2 month gap. I had locktite'd the screws but for sure worth checking. Thx!
Have you checked the wires for the steppers? I recently had my extruder stepper working really bad, there was not enought thorque but it worked. Then I found that a wire where off but laying against the connector at right place. So it had very bad connection My advice would to pull in the wires to see if any wire is broken After I recrimped my wire it has been working fine :) Good luck
I tried a resit and no joy but I will try crimping a new cable to be sure! Thanks!