I have had this come up a few times but last night was more frustrating due to the length of print. The unit gives a “failed to pull back the filament” error and I see that the unit has not wound up the spool properly and there is a pile of it inside the AMS… This has happened with random and bambu filament. Any known fixes for this?
Thanks
Is is only occurring on one slot in your AMS?. The feeder motor may be failing or has failed on that slot in your AMS. Same thing happened to me.
No, it has happened in at least slots 1-3
If the filament isn’t winding back onto the spool it normally means the spool isn’t sitting on the rollers correctly. Also check to make sure the spool is not bulged and catching.
Ok I will inspect the positioning more closely. It has happened with at least three types monoprice, bambu and creality and all were plastic
I have this problem too after the last update. Really annoying. My spools are fit correctly it’s just a stupid bug.
I have to say that I notice more an more failures creeping in and that not a good development…
How do you fix this? I have the same error, though the filament is out. I don’t need that slot for my next print, but I can’t get rid of the error.
Still having this very annoying bug. It want to load from an external spool while there is no spool! Lights flashing red. Today my printer was air printing.
Bambu what gives?? HELP
Unfortunately I had the same problem. I spent an afternoon trying to resolve it and nothing. It was only after using the Bambu Handy app and downgrading the 3D printer’s operating system that I was able to resolve the problem.
When it happened to me i couldn’t pull the filament toward the spool so i removed the tube off the back of the AMS and gently pulled the filament out the back of the AMS unit. First clear all tubes to the extruder.
I was wondering if you found a solution to this problem?
I currently have 2 AMS units. The first one I have had for ~6 months with a few random issues, but over all good.
I added a second one last week and now I’m having issues with both.
When changing colors and rewinding the current color on it seems like the “extruder” is pushing the filament toward the spool faster the spool is spinning so it end up going up over the edges of the spool and then gets hung, pausing the print.
At this point I have had it happen with slots 3 & 4 on the original AMS and slot 4 of the new AMS. I have printed with these brand spools on the original AMS prior to this with no issue. The only other thing that has changed is the bowden tube is now longer than before due to having move the original AMS off the top of the printer.
I would check both ends of the new ptfe tube to make sure the ends where cut square. Also make sure the ends are pushed in firmly to make sure there are no gaps inside the couplers/connectors.
I also got this 2 times just yesterday, both times the motor in the 4 way under the AMS seems like it isn’t rewinding correctly. Checked the entire path for breaks, but the filament was fine, not even overly chewed up like you would expect if a motor was trying too hard.
It appears to have retracted just enough to clear the print head correctly, then stopped, and I had to back it out the rest of the way by hand before disconnecting the AMS to safely back it out all the way to the spool.
Using all stock tubes, and have made zero changes to the stock machine, and it’s only a few weeks old.
This indicates there’s a bind or too much friction somewhere.
Have you opened the AMS and took a look at the PTFE tubes? They are consummables. If they wear there’s too much play within and this causes issues.
It could also indicate a curve that’s too sharp. If you havn’t changed those then maybe just look for wear there as well
Lastly there are 100 fixes for this problem on Makerworld.
This is the only one I’ve ever used.
I too have this issue (0700 8003) an a brand new X1c with AMS in single color/filament prints each time it wants to finish the print (at 98%).
I tried several things so far:
… what I forgot to mention: I cancel the print after it being stuck at 98% and then do an unload through the filament tab on the printer → NO ISSUE.
I had something like this happen a few times with a particular filament. I assumed it was due to heat creep and once it cooled it was able to retract it.
FYI: I found my issue - the filament cutter was not working properly. Not that i fixed it, everything works fine.
I recently had this doesn’t pullback error multiple times. Nothing changed on the printer. No jamming of the spool so it’s something between spool and extruder.
How to clear it:
Cycle the power and try to unload filament.
Turn it off and gently try to pull toward the spool. Haven’t found this to work well
Disconnect the ptfe from the box on the back and pull filament from the extruder. Then pull into the spool. Or cut filament at the spool and pull towards the back of AMS. Gently
How to correct it:
I found the tubing was grabbing the filament.
Could replace sections of tubing. Eliminate all sharp bends in the tubing. Large gentle turns are best.
For some reason the filament was grabbing on the coupler outside the unit just off a rubber guide tube that goes into the unit. I replaced that coupler with a 1by4 Bambi diverter and it works great. I did make a mount for the diverter and attach it to the back. I really like that diverter because I can easily feed the side spool into it.
Cutter might not be working as mentioned above. So replace it.
AMS motors might be bad but I haven’t seen that thankfully.
One way to find out what’s holding the filament is to disconnect the tubing as it’s trying to pull back. In my case that freed it and told me where the problem was.