I realize this is a lot of information but I’m trying to be as thorough as possible before hand and really detail the steps and observations I’ve had.
- This is a X1C with AMS bough 11/2023.
- Exclusively used Bambu Basic PLA.
- Unit shows 590 hours
- Device is up to date
- I have done basic device maintenance(clean rods, grease screws, replaced cutter/wiper, oil idler pulley)
I came home today to a print that never really finished. It is like it just stopped extruding filament at some point but never error’d or stopped printing. The screen said it was done with the layers, something like 1,100/1,100 and was at 99%. The screen had an error that said ~“problem retracting filament”. This is how I found the print.
There was or is no clog or blobs or anything anywhere that I’ve found. Not even any spaghetti in the chamber.
I have followed this video but am not able to feed filament through.
Though I am able to feed the filament through the hotend itself if I unscrew it but leave it plugged in.
I have followed this article twice now trying to see if there is anything wrong but everything seems pretty okay and normal. There were no clogs, blobs, stuck pieces of filament. I brushed and wiped with a microfiber as suggested, but there really seemed like very little to clean.
https://wiki.bambulab.com/en/x1/troubleshooting/extruder-clog
Even before taking everything apart the yellow gear spun with very easily, little to no friction or hesitation. It wouldn’t free-spin but was very easy and smooth.
https://www.youtube.com/watch?v=l8VqZNBw5a4
Though attempting to feed filament through the mechanism after I had it out experienced quite strong hesitation at first and then would spin/rotate pretty free but seemed a little rough. Unsure if this is normal.
This is it trying to load from the AMS, ignore towards the end, I was trying to position the phone towards the back to get a better look at the yellow gear as it tried to feed the filament on the next attempt.
I also noticed after some of this troubleshooting it was producing this hum/buzz for awhile but would eventually stop. Towards the end of the video it gets slightly louder, that is heard in person as well. It would be at one tone/volume for 5-8seconds we’ll say, and then pitch up or get slightly louder for 1-2seconds before dropping back down.
I also read some other threads & comments about the Filament Buffer possibly causing issues, but from what I observed mine seems to be functioning pretty fine. Plus that wouldn’t explain why I can’t even feed it directly down into the extruder without even any PTFE tubes.
(You can hear some of the hum/buzz in this video too as I bring the camera out and then back in the machine)
I feel like its narrowed down to one of the below, but I’m open to other troubleshooting suggestions or ideas of what the problem could be.
- Hardened Steel Extruder Unit (possibly just the gear assembly?)
- Extruder Motor
edit: I have filled out a support ticket with Bambu and let it upload the log from when the print failed, but figured I’d post in the forums too.