Weird massive XY-shift
Hi guys!
I've been printing for 1/2+ years with my prusa and never had this problem before - a massive shift in both X and Y direction at the same time.
[attachment=1]IMG_5592[1].JPG[/attachment]
This makes me think it's not the occasional belt skip (which I've had my fair share of), but something new and I don't really know where to start. The same model (different g-codes) has had this problem twice now. Perhaps the only unusual thing with this model (for me) is that the g-code is about 10mb in size when they are usually around 2-5. But file sizes houldn't be a problem, right? There's no layer adhesion problem, speeds are on the safe side, belt tensions are ok, the xy-cables don't seem to get stuck either... Apart from the inner supports, the quality of the print seems OK up until whatever happened that caused this. What else could check? Is possibly an octoprint issue?
Additional wierdness is
1) the lump of brown snot in the top right corner of the model (second photo). What do you suppose could have caused that and could it be related to the shifting?
2) XYZ calibration was completely out of whack and had to be reset / recalibrated
[attachment=2]IMG_5593[1].JPG[/attachment]
Re: Weird massive XY-shift
I had a layer shift problem recently that I'm 99% sure was caused by filament sticking up when it was starting a top layer for a hole over 10% grid infill. At first I thought it was because I had LA enabled while printing from Octoprint, but I tried the same model from the SD card and found another layer shift at the same height except this time one of the parts was knocked across the bed a bit. Had a burnt blob kind of like that too. I figure the nozzle was getting stopped by the filament and stalls until it softens/melts the obstruction enough. The force might be enough to screw up your XY calibration too.
Re: Weird massive XY-shift
Well I changed the following things which resulted in a successful print:
1) Slightly different infill and support settings halving the file size to 4,7mb
2) Printed using high-power settings, after having read elsewhere that printing in silent mode could cause overheating and/or missed steps. This is indeed the longest print I'd done before so this would be my main suspect so far.
3) Changed the filament (not enough left on the spool). I tried to simulate various filament-snagging-scenarios but I haven't been creative enough to show that this could have been the cause. But yeah - totally maybe. I definately need to build a filament guide anyways =)
4) doubled the Z-retraction height to 1,2mm to minimize risk of knocking into things (don't know if this was entirely necessary or smart)
A camera is waiting in the mail - next time I shall catch Chaos in action!!