I just upgraded (I think, lol) to the AMS 2 Pro from the AMS Lite on my A1 printer. On my very first test print, the first color finished, but got an “unable to pull back filament error” and the print could not continue. While investigating it was clear the filament was locked in place. There was no motion from gears – the spool was just literally tethered to the feeder.
Switching the A1 off and on again, then refreshing the filament slot operated as if everything was normal. On my second attempt it cleared this color without any issue at all.
However this has me concerned there’s an issue with this AMS unit or possibly with the them in general. Has anyone else seen this? If so, how chronic is it?
The first thing I would check is the filament cutter. How old is it and has it ever been replaced? Other things that can cause this are heat creep (not likely on the A1) and filament without a consistent diameter (rare).
I might be getting a similar issue. When I try to load a filament, it gets stuck right after leaving the AMS unit and gets to the PTFE Tube and I am not able to print with a single or multi color unless I manually feed it to the extruder.
Would love advise on what could be the issue with this as well.
I still don’t know what happened, exactly. It’s been working fine since the power-reset. I’ve done 6 or so multi-color prints and have not seen the issue since. I don’t have that buffer unit with my A1, it uses a separate hub instead. But to answer your question, the filament was frozen in place at the feeder gear in the AMS. It literally offered no movement at all.
So I seem to be good now, but that was a big scare out of the gate. I hope it doesn’t recur in the future.
I’m having the same trouble. Using the new AMS hub for my A1, print will complete fine but I get the filament pullback error every time. This happens with different filaments in different AMS slots. As soon as I disconnect the PTFE tube from the top of the tool head, the AMS pulls back fine and the job completes.
This works somewhat for a single-color print, but no way it’ll work on a multi-color print. I’m wondering if the new hub has something to do with it.
