I know that this question has been asked over and over again. I have read a LOT of similar issues in the forums, but not quite the same as mine…perhaps?
Every single print that I do in any filament I have tried (I have used PLA, PLA Carbon, ABS and PETG only) - once the print hits 99% and goes to do the retraction, it fails to retract from the printhead. Every time. No exceptions.
The only way that I can get it to retract is to cancel the print, pull the items from the print bed, home the machine, heat the hotend to 250 and use the buttons on the front of the machine to slowly retract the filament. While it is doing that, I keep my hands on the PTFE Tube Connector on the back and basically keep trying to pull the tube until it actually releases (I can’t pull it before it’s heated and retracted a bit as it’s definitely stuck or under too much pressure). After that, I do a filament unload and load and it’s good to go.
This happens with all slots on the AMS. I have tried printing the various versions of the thing that changes the angle of the filament going into the tube. I’ve followed troubleshooting to take apart the AMS to make sure there are no clogs. I have replaced the PTFE tubes. Nothing has worked. I REALLY want to use the AMS for multi-color prints, but I just keep getting failure after failure.
It sounds like perhaps your filament cutter isn’t working? The head should move to the front left corner to activate the cutter before retracting. Have you tried manually activating it on the print head and seeing if the filament retracts easily by hand?
Hmmm. No I actually haven’t tried doing that manually. I DID replace the cutter, just in case (which I forgot to mention). But I will try doing that when I get home (as I have a print waiting for me with that error right now). If it’s something that simple, I would be ecstatic.
Ok. So I tried pressing the cutter manually. Nothing happened at first. So I opened the front cover and I noticed it was on a pretty high angle. So I lowered the cutter, replaced the cover and tried again. It worked this time.
Fast forward to this morning before I left for work and my print had the same issue. So I tried manually cutting again - but to no prevail. I ended up using my old method.
But I feel like you still may be correct and this is making me wonder - how is the blade supposed to be sitting? I feel like its direct cut path hits the filament sensor rather than any actual filament…
Sorry I should have looked before I asked the question. I just looked at the guide on replacing the blade so that I could see the angle that the cutter is SUPPOSED to be at. And wow…just wow. Nope. This is 100% my problem because my cutter is cutting literally nothing because it’s not even sitting correctly. Which means it must have been this way since the very first time that I had to unclog my extruder…which was a year ago…facepalm. I am humbled and embarrassed, but THANK YOU for putting me onto the cutter because I completely overlooked it, thinking that it “couldn’t be that”.
Just in case someone else runs into this issue. I took apart AMS, AMS hub (then broke it), replaced hot-end twice, upgraded extruder. All to figure out I had the filament cutter flipped up instead of inserted into the slot!
I went down multiple paths and forums to get to this unbelievably easy fix and user error. Misery loves company.
Having this exact issue, happens nearly every time for me and I’ve changed just about every part of the extrusion process. Only thing I haven’t changed really is the extruder filament sensor.
Incidentally next time it happens, don’t turn off the printer, just leave it for about 30 mins or so and go click ‘finished (resolved)’ and nearly every time it will retract fine
did you actually swap out the cutter blade? the thing in the top left of the printer that cuts the filament could also be broken, ive seen that before. try checking that as well
Yeah changed the blade even though the old one was still sharp enough to cut. The mechanism all seems to work fine as I’ve examined the end of the filament after removal and it seems a clean cut
Hey! It seems the extruder filament sensor was the issue! Since changing it yesterday I haven’t had any AMS issues and prints have been better than ever
UPDATE: no, it hasn’t fixed it. just got to the final layer of the print and the AMS red lighted again and the filament won’t budge. after numerous retries it retracted then red lighted on re-entry
, we have all been there at some point. Happy printing
