Filament is pulled but nothing after on X1C

Hi there! I have more than 2300 hours on our printer. The usage here at work is pretty basic stuff: inserts for boardgames, various items like tropgies or medals, nothing fancy, always mono-colored.

We use PLA filament, mostly Overture, Polymaker and eSun brands. We used some cheaper one too but rarely.

Lately, the head was making clicking noises and not pulling the filament. I tried everything “official” and a lots of non-official thinks also. Nothing worked:

  • no clogging
  • some extruder internal gears were worn out a bit
  • I cleaned and greased/oiled eveything with the original Bambulab products and again with WD40 and other silicon lube brands
  • Replaced the whole Hotend assembly (.04) AND the whole extruder assembly plus the cutter for good measure
  • I already replaced the TH Board Set for the V9 version a few months ago.
  • I unplugged the PTFE tube to get the filament directly through
  • I checked the motor and I can’t even try to stop it turning, it’s very strong, so not the motor
  • There is no error message appearing
  • I read every topic that tlaks about extruding problem in this forum or even on reddit.

The filament is being pulled when I load it or pushed when unloading it but if I simply try to get the filament out, it still makes the grinding sound (more than 50% quieter but still there) and nothing comes out.

I’m getting a bit frustrated at the moment so before I throw that thing out the window in the parking lot I need some help. Did I forget something somewhere?? Sometimes it’s a small thingy or procedure issue but I am out of ideas. Pretty sure it’s something I’ll say “that easy?”. At this point, I wont get frustrated if it’s simple, I just want it to work!

Thanks for your help all!

How are you trying to remove the filament?

With the Unload function (like the pulling…)

Plus I tried with the up and down arrows manually

Has the all PTFE tubing been replaced?

You dont mention if an AMS is in play, and I would suggest to try to run your test from an external spool if you’re using AMS currently. AMS motor, PTFE plumbing, and the AMS Hub all could be potential problem points delivering the tip of filaments into and out of the extruder mouth.

Replaced but even without tubing at all

No AMS, only the basic printer with one spool

What happens if the filament is fed directly to the extruder without any PTFE tubing? Disconnect the PTFE from the extruder and try to feed an unencumbered length of filament into the coupling at the extruder.

Like I said previously, when I pass directly through without the tube, same thing happens. I din’t understand, everything that is mechanically related to the filament has been replaced…

Is the hot end properly installed? Can you shine a light up from the nozzle and see it at the point where the filament enters the extruder?

That’s what I see in the new hotend… Isn’t the filament supposed to melt when it’s heated? I cranked it around 250deg. Could it be that simple? Now how can I get this outta there?

It does but the filament cutter can only cut the filament above the nozzle. This leaves filament in the nozzle which is purged out when the next filament is loaded.

You don’t need to but if you really want to get it out you will need to do a “cold pull”.