Y-Axis failing axis selftest but seems to move fine
This is an odd one, today the extruder started clicking and grinding up the filament so while I've been sorting that I also updated the firmware and ran a selftest the first time I put it all back together and it failed on the Y-axis, now the Y-axis seems to move freely and I've had no issues with prints that might be caused by a axis not moving correctly but every time I run the test the Y-Axis fails and I've no clue as to why, anyone had an issue like this or know of a fix?
Link to a video of the failure;
https://photos.app.goo.gl/wG3msbRFSC1DRbQQ7
Best Answer by Sp4rkR4t:
It's passing now, loosened up the Y belt a bit and gave the rods a good clean down and re-lube. I didn't notice when I first encountered the issue but there was a bit of resistance when sliding the build plate forward I guess it was just a build-up of gunk.
RE: Y-Axis failing axis selftest but seems to move fine
This is an odd one, today the extruder started clicking and grinding up the filament so while I've been sorting that I also updated the firmware and ran a selftest the first time I put it all back together and it failed on the Y-axis, now the Y-axis seems to move freely and I've had no issues with prints that might be caused by a axis not moving correctly but every time I run the test the Y-Axis fails and I've no clue as to why, anyone had an issue like this or know of a fix?
Link to a video of the failure;
Either the y-axis linear rods don't run parallel or the belt tension is too high. Are the linear ball bearings lubricated and running smoothly?
Prusa also has some tips ready: https://help.prusa3d.com/en/article/layer-shifting_2020#prusa-mini
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE: Y-Axis failing axis selftest but seems to move fine
My guess is that the position of the linear bearings in the y-carriage is not correct.
The linear bearings can be moved within the y-carriage during the assembly process (in y-direction). On one y-axis rod there are two bearing, on the other rod there is only one. The two bearings which are on the same rod have to be pushed in y-direction towards each other. This is only possible when the bearing clip / u-bolt is loose. If this is not the case, you won't be able to reach the full travel of your y-axis.
RE: Y-Axis failing axis selftest but seems to move fine
@sonic_2_1
Maybe replace the U-bolts with self-printed housings for the linear ball bearings. I have done this on all my printers: https://www.prusaprinters.org/prints/45941-gehause-fur-linear-oder-gleitlager-15x8x24-lmu8-od
On thingiverse you can find similar constructions.
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE: Y-Axis failing axis selftest but seems to move fine
It's passing now, loosened up the Y belt a bit and gave the rods a good clean down and re-lube. I didn't notice when I first encountered the issue but there was a bit of resistance when sliding the build plate forward I guess it was just a build-up of gunk.
RE:
@karl-herbert ****************************
Wish there was a method of marking an item as a solution. I have been dealing with the Y Axis failing and first layer shift on large items for months. I even spent a bit of time emailing the support team back and forth and their only recommendations were to loosen or tighten the belt, or reseat the stepper cable. Somehow I managed to pass over (not see) your response here even though I had read this exact thread multiple times. I loosened the carriage bearing screws, and indeed I was able to shift both linear bearings in slightly. The made a very prominent click when the fit into place. I tightened the screws back up and lo and behold, my Y Axis access woes are over.
With the greatest sincerity, Thank You!!!!
RE: Y-Axis failing axis selftest but seems to move fine
I had this same problem and had a different solution. The heat bed cable got caught on the electronics box, preventing it from fully moving to the front. When it would go to the rear, it would hit and try to keep going. I read this thread and was about to troubleshoot. I then noticed the heat bed cable on the rear edge of the box.
I moved it out of the way and it passed the next self test.
RE: Y-Axis failing axis selftest but seems to move fine
My Y axis was failing also. Same grinding when the print starts. The internet brought me here.
MY ANSWER:
I know this is super basic but the heat bed wire was getting caught on the back of the controller box. The Y axis couldn’t come forward all the way. That’s literally it. Your problem was probably resolved the same way since you manipulated the wire when cleaning the rods and loosening the belt etc…
I know this really silly fix doesn’t seem like the complicated problem we experienced but it may just be the right answer for many of us.
RE: Y-Axis failing axis selftest but seems to move fine
i have spent alllll day trying to fix this. I've been on chat with tech support. then I read your comment and ran another self test while lifting the y axis wire and it passed the test!
thanks so much! i was about to yeet the printer out my window!
L
RE: Y-Axis failing axis selftest but seems to move fine
My solution just now, echoing some others on this thread:
- factory-assembled, have been using it for months with no trouble
- suddenly repeatedly failed y-axis test, even after adjusting y-belt tension and cleaning the rods
- i loosened the rear left bearing and nudged it even more towards the center by a tiny tiny tiny bit (and then re-tightened, obviously...)
- worked!
RE: Y-Axis failing axis selftest but seems to move fine
It's passing now, loosened up the Y belt a bit and gave the rods a good clean down and re-lube. I didn't notice when I first encountered the issue but there was a bit of resistance when sliding the build plate forward I guess it was just a build-up of gunk.
This was the same symptoms as I experienced before total failure of the stepper. Resistance when moving, but seemed to free up after I re-greased and cleaned everything, so I assumed it must have been the linear bearings. I had a complete failure about 12 print hours later. Might be worth checking the internals of the stepper so that you don't get a failure mid-print.
My thread below: