Notifications
Clear all

X Layer Shift, but 'Y Crash' reported.  

  RSS
CraigW
(@craigw)
Active Member
X Layer Shift, but 'Y Crash' reported.

Hi,

I have an MK3S which has up until a couple of days ago been working without issue. However, it now will layer shift in the X-direction on almost every print, but at varying Z-height.

I watched it and caught it at the exact point it layer shifts. It says 'Crash Detected' and then rehomes X/Y and continues printing, but the X is now shifted ~2mm, with perfect alignment still on the Y-axis. Strangely it always reports that the crash occurred on the Y-axis, with zero X-axis crashes.

  • Bearings on X and Y are well lubricated as part of my maintenance regime.
  • X-axis belt status is 275, Y axis belt status is 279.
  • Belt tension 'feel' is approximately the same as my other MK3S
  • Same file prints perfectly on my other MK3S
  • Belts do not rub on plastic and belts are planar with extruder, X-axis stepper and idler.
  • X-axis and Y-axis both move very freely, with just as much, if not less, force than my other Mk3S without the layer shifting issue.
  • I've tried loosening the bolts immediately near the X-axis bearings on the extruder try and reduce any excessive compression, no avail.
  • Occurs in both Normal and Silent mode
  • Latest firmware

Can someone please offer some advice?

Cheers,
Craig

Posted : 04/04/2021 4:37 pm
Diem
 Diem
(@diem)
Noble Member
RE: X Layer Shift, but 'Y Crash' reported.

Can you show us  picture of the back of the printer - preferably with a print in place, so we can see the layout of the cables and the back of the Extruder?

Cheerio,

Posted : 04/04/2021 6:50 pm
Dan Rogers
(@dan-rogers)
Noble Member
RE: X Layer Shift, but 'Y Crash' reported.

download and print that little belt tension tool gcode from prusa - you can't rely on those #'s from the sensors.

 

Posted : 07/04/2021 2:05 pm
CraigW
(@craigw)
Active Member
Topic starter answered:
RE: X Layer Shift, but 'Y Crash' reported.

@diem

Here are few photos of the printer in action. It sits on supports about 60mm from the floor to allow more air flow around the Y and Z steppers.

I resorted to turning off crash detection and have so far managed 4x 6-8hr prints with no layer shift issues. So this doesn't get to the root cause of the problem and solve it, but it is a work around which seems to be working so far.

@dan-rogers thanks for the tip, that looks like a handy little tool. I'll give it a go once I'm finished with the current job.

Posted : 07/04/2021 2:25 pm
Diem
 Diem
(@diem)
Noble Member
RE: X Layer Shift, but 'Y Crash' reported.

Does this only happen with larger prints that fill the bed?

Here is a detail from your second picture:

The zip-tie is protruding to the right (as we look at it) of the cable bundle and may contact the frame at the extreme position - this could be enough to cause layer shift.  Rotate the tie to the top of the bundle out of the way.

Does this help?

Cheerio,

Posted : 07/04/2021 3:37 pm
CraigW
(@craigw)
Active Member
Topic starter answered:
RE: X Layer Shift, but 'Y Crash' reported.

@diem

Thanks for the suggestion, I'll fix this, but layer shift was occuring on much smaller diameter (30-40mm) parts as well.

Another 24hrs of printing since my last post with crash detection disabled, doing the same large diameter/whole bed prints and no layer shift evident. Unfortunately it looks like disabling crash detection is the 'solution' on this one.

Cheers,

Craig

Posted : 08/04/2021 3:11 pm
Share: