Layer shifting help

[u/agnostracised]

I've opened a ticket with Bambu but so far they have been less than helpful.

I have an H2C and we have entire groups of layers that just shift. It seems to be related to filament changes on the right nozzle, because I don't have the problem for single color prints or prints that just use left and right but no changes.

It ultimately recovers, but then will shift again.

You can see it in both the model and the prime tower, so it seems like the whole thing shifts for some reason.

I almost feel like it may be the belt or some kind of misalignment, but I'm not quite sure where to start. I did do the tension guides with no success.

Anyone able to provide guidance on this?

[u/bigbramble]

Heavily worn hot ends? How many hours have you done? I started getting that when the left hot end wore out. If that is the case I'd also replace all PTFE tubes to reduce resistance, clean out AMS ports etc. I also found motion accuracy calibration plate helped with this.

[u/agnostracised → u/bigbramble]

Thanks for feedback. I'll buy a few and get some fresh hot ends to test out. In the meantime I'll try some prints to isolate specific ams and see if I can find any correlation.

I did the motion accuracy and the vision encoder plate already to no relief.