What would cause filament to come out of the top of the extruder?
Last night a 9 hour print was nearing completion when apparently the filament stopped being pulled into the extruder. What would cause that? I haven't printed much (perhaps a total of 60hrs) but I've not had this happen yet. Was it just not able to pull the filament in for some reason? Anything I can do to make sure this doesn't happen again?
I have the standard double spool holder.
RE: What would cause filament to come out of the top of the extruder?
It is really hard to picture what you are describing.
Was the filament unloaded? Maybe a picture would help.
RE: What would cause filament to come out of the top of the extruder?
@robert-rmm200
I can't post a picture as I have reloaded the filament and started printing again.
What I'm saying is that when I came to the printer this morning there was no filament going into the extruder. The spool looked normal and the end of the filament had sprung back up into the spool. So at some point during the print the filament actually pulled out of the top of the extruder and the print stopped with about 2mm left to go. There were no errors reported.
RE: What would cause filament to come out of the top of the extruder?
Did your filament perhaps snap? Some filaments can get very brittle as they age and absorb moisture from the air.
RE: What would cause filament to come out of the top of the extruder?
Did your filament perhaps snap? Some filaments can get very brittle as they age and absorb moisture from the air.
Possibly, I don't really know. I keep the filament in plastic bags with desiccant to keep it dry.
Something that I'm just reading about...could I have continued the print somehow? I didn't see any indication on the screen for an option to continue, but I've read that should be possible. Is this a difference between the MK3 which I have and the MK3s?
RE: What would cause filament to come out of the top of the extruder?
Sure sounds like your filament unloaded if there was no filament in the hot end.
If it unloaded, it could be an intermittent failure of your filament sensor.
If the filament broke, that should have been sensed as a no filament condition, and the two inch piece would have been unloaded - and there for you to find.
If your printer continued and thought it finished the print - there is no way to go back to the point of failure.
Still a lot of guessing on my part. No idea what the printer was doing when you found it the next morning.
RE: What would cause filament to come out of the top of the extruder?
@robert-rmm200
When you say "Sure sounds like your filament unloaded if there was no filament in the hot end" do you mean unloaded out of the bottom of the hot end, or out of the top of the extruder?
I think there was still filament left in the hot end. When I loaded new filament whatever was left in the hot end immediately started flowing out as I re-loaded the filament. There was no 2" piece left for me to find after the failed print.
I guess I'll just keep printing and see if it happens again. THANKS for your help.
RE: What would cause filament to come out of the top of the extruder?
There is no way for the filament to "unload" out of the nozzle. The extruder has to actually "push" it out using new filament.
Unload means the extruder runs in reverse, dragging the old filament up and away from the nozzle - and out the top.
When the filament sensor detects no filament, it goes through that unload cycle to get ready for new filament.
If you are there when it happens, you can load new filament and the print will resume. Otherwise it times out and turns off the heaters.
RE: What would cause filament to come out of the top of the extruder?
Last night a 9 hour print was nearing completion when apparently the filament stopped being pulled into the extruder. What would cause that? I haven't printed much (perhaps a total of 60hrs) but I've not had this happen yet. Was it just not able to pull the filament in for some reason? Anything I can do to make sure this doesn't happen again?
I have the standard double spool holder.
What did the end of the filament (then back at the spool), look like? What did you experience when you reloaded filament, did a clog get pushed out? Maybe in the middle of the print a clog developed and then the gears ground away at the filament until the filament separated and the loose end wrapped back to the spool?
Every man I meet is in some way my superior. --Ralph Waldo Emerson
RE: What would cause filament to come out of the top of the extruder?
What did the end of the filament (then back at the spool), look like? What did you experience when you reloaded filament, did a clog get pushed out? Maybe in the middle of the print a clog developed and then the gears ground away at the filament until the filament separated and the loose end wrapped back to the spool?
The end of the filament had a little bit of stringiness to it but nothing significant. When I reloaded the filament it loaded just like normal. I didn't notice any extra globs etc. But then again I'm very new to this.
I have since printed several things including one 9hrs print overnight and everything seems to be working just great. No idea why this happened.
RE: What would cause filament to come out of the top of the extruder?
What did the end of the filament (then back at the spool), look like? What did you experience when you reloaded filament, did a clog get pushed out? Maybe in the middle of the print a clog developed and then the gears ground away at the filament until the filament separated and the loose end wrapped back to the spool?
The end of the filament had a little bit of stringiness to it but nothing significant. When I reloaded the filament it loaded just like normal. I didn't notice any extra globs etc. But then again I'm very new to this.
I have since printed several things including one 9hrs print overnight and everything seems to be working just great. No idea why this happened.
Hmm...seems not to be what I was thinking might be the issue. Good luck! You’ll figure it out; that’s half the fun as far as I am concerned!
Every man I meet is in some way my superior. --Ralph Waldo Emerson
RE: What would cause filament to come out of the top of the extruder?
If you have a long print you don't want to risk - I do suggest turning off your filament sensor for just that print.
It is not needed to print, and a failure there can ruin your print.
Leave it on normally so you can detect any intermittent issues.