Question about Print Stop and filament retraction

Bambu Lab X Series Bambu Lab X2D
1

Hi,

I just got my X2D last month, first timer in 3D printing and this is my second post.

I got into a weird situation yesterday while the printer was printing at home. At some point it started printing spaghetti everywhere (not a printer specific problem, but a specific print that constantly fails for a reason and I was trying stuff), I got a notification on my phone, got up and saw it and hit stop.

When the printer stopped, the filament stayed inside. It didn’t purge or retract back to the AMS pro 2. So I hit extrude down from the settings using the printer’s panel, and it feed it normally and made a nice thin line down the plate. I hit extrude up, the filament went backwards a bit but not all the way. Then I hit extrude down again, and nothing happened. Then I hit re-read on the AMS nothing happens, hit reload nothing. I tried to manually retract the spool but it had too much tension (I pushed the tab on the AMS to release the filament) I stopped because it felt wrong and possibly could damage the AMS. Okay I said, I should have read something online because now something is “broken” and I have to open the print head. So I thought I’m doing a surgery any way, let’s see if it will print anything. Thankfully it did and when it finished it retracted the filament and now everything is fine.

Any how, here’s what I did:

  1. I stopped the print.
  2. Saw that the filament didn’t retract.
  3. Hit the Extrude Down and Up. Still the filament didn’t retract.
  4. I printed a small usb cap, no issues during the print, it finished and the filament retracted normally.

My question is this; I was at home and caught it right when it was happening. If I’m not at home and hit stop from the app, when I return how exactly am I supposed to fix it when everything would be cold and the filament still inside and not retracted?

Obviously I will have to heat the nozzle to soften the filament, but then? Do I disconnect the PTFE tube from the printer head, manually retract the spool and perform a cold pull to clean the nozzle or there is another way? Even so when I caught it while it was “hot” right there, should I have done something different?

2

Did you try the UNLOAD fuction for the screen? You should select the correct spool and then push unload. This function will manage both printer and AMS to do the correct things at the correct time.

3

Do not pull the filament forcefully while cold. Heat the nozzle to its normal printing temperature. Then use the printer’s normal retract or unload function. If unloading fails, disconnect the toolhead PTFE tube. Gently pull the filament while the nozzle remains hot. Clear any blockage if the filament remains stuck. A cold pull can clean suspected nozzle clogs. Your AMS likely wasn’t permanently damaged or broken. Avoid forcing the AMS spool backward manually. That resistance usually indicates filament remains engaged. Do not pull the filament forcefully while cold.
Heat the nozzle to its normal printing temperature. Then use the printer’s normal retract or unload function. If unloading fails, disconnect the toolhead PTFE tube.
Gently pull the filament while the nozzle remains hot. Clear any blockage if the filament remains stuck. A cold pull can clean suspected nozzle clogs. Your AMS likely wasn’t permanently damaged or broken. Avoid forcing the AMS spool backward manually. That resistance usually indicates filament remains engaged.

4

Aah, yes the Unload button. My brain, apparently decided to tune it out. Now that I looked at it again, when the print stopped, I should’ve hit Unload and the printer would have retracted, cut and unload the filament.