Hi everyone,
I left my P2S alone for a month and now it won’t extrude if an AMS is involved.
WHAT HAPPENS:
- Attempts to load filament from EITHER of my two AMS 2 units (and any slot) results in the filament spooling all the way to the extruder. It sits there for a bit, then winds back, and tries again repeatedly.
- It eventually throws a ‘resistance too high’ error.
OTHER INFORMATION:
- If I stop the process when the filament is at the extruder, if I manually take control of the extruder, it will load just fine.
- Loading from an external spool also works fine.
- Printing (single colour) is working as normal.
- Filament Hub spring travel seems to be normal.
THINGS TRIED:
- Used fresh sealed filament in the event that somehow all of my existing filament had gone bad (!)
- Performed several Cold Pulls - nothing strange observed.
- Examining PTFE tubes and routing - all looks normal.
- Took off Filament Hub. It was VERY hard to remove the PTFE tubing between the hub and the printer (even with the specialist tool). It was jammed. I did get it out and it didn’t look in best condition at the end. Replaced. No change in behaviour.
I have raised a support ticket with Bambu but am still waiting to hear back.
What else should I be trying / could be the issue?
Bumping this one to see if anyone has any advice.
(Support ticket that I raised 3 days ago has still not had a response)
Just a quick question as you seem to have covered the usual suspects. After this happened:
Did you have another very close look at the PTFE ends? If the are slightly frayed or have been deformed to no longer have a clean, 90°, they can bring in a lot (!) of extra friction. But since they are usually installed with a margin, you can cut the tips for a clean finish.
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Addendum: (Probably) not related but freh, sealed filament must usually be assumed to be moist. Those bags only slow, but do not stop, moisture uptake. And they have spent weeks at sea…
I have the exact same issue, but with my P1S.
I JUST received the printer and it wouldn’t even load my first filament, when I use the AMS.
Firmware is up to date and I’ve tried different things from youtube and the internet.
Currently reset the factory settings and see if that helps.
Mine goes beyond the extruder though, and stops right before the it goes inside the machine.
To clarify, mine goes right into the extruder (well, as far as I can see visibly). The extruder gears turn briefly, then it gives up and the AMS retracts the filament.
External spool feeding and printing works just fine.
Support have come back to me, confirming there is an ‘abnormal buffer signal’ showing in the logs. I need to take a video of the spring action in the buffer – will update as this progresses.
My filament won’t make it to the extruder. It has been a weird issue. I can print without the AMS with no issues, but it stops right before the extruder and gives me a filament stuck message. Hoping to find a solution.
Welcome to the forum @MisteryBacon
It is actually reasonably common that the filament does not reach the print head. The most common issues arise from:
- PTFE’s not fully pushed-in => Push 'em in fully
- PTFE Ends not cut straight at 90° => Check PTFE Ends for cut quality/fraying, re-cut if neccessary
- PTFE paths too long and with too tight bends => Tale care to avoid sharp bends and shorten PTFE lengths as far as possible with your set-up
Mostly, these come from the AMS to printer path but they can also occur in the AMS. However, in that case, problems are usually slot specific.
There’s more, but lets hope it is a simple fix rather than a more complex issue with the buffer(s), hub or AMS motors.
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I haven’t adjusted the PTFE tubes at all and nothing has changed since my last successful print. It’s strange because it’s stopping just after the tube connector from the AMS after the buffer, so it’s not made it to the extruder. There’s no broken filament inside of there. No real indication that AMS motors aren’t working. I’ve looked at a ton of the forum posts but trying to fix this has been super frustrating.
Does it happen with all slots of the AMS or just one?
Does it always stop at the same location? And do you have a pic? There are a number of possible set-ups and combinations. And of course differences between P1’s and P2’s…
Have you tried hand feeding through the buffer? And already inspected your PTFE ends?
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This along with the resistance too high and with the external spool working sound very much like the buffer isn’t fully traveling correctly. If the buffer doesn’t tell the AMS to send more filament, the extruder pulls the filament tight all the way back to the AMS and the PTFE also gets jammed very tightly into the connectors.
I know you replaced the buffer, but what I’ve seen the problem is actually the floating PTFE not being straight as the filament jockys it around in the buffer, and I think replacing the buffer doesn’t necessarily fix this. I think this misalignment causes the bind that pulls everything way too tight.
Sorry I can’t recommend a specific solution, but there are any number of PTFE alignment/extraction solutions for this available in the 3d Print library.