Constant PLA oozing at any temperature
Hello,
My printer was working marvelously for a while
Suddenly, it started to ooze PLA. The same PLA I used all the time is now oozing out of the nozzle even at idle.
Additionally, it is impossible to print anything because overextrusion makes every print instantly blob and become unusable.
I have tried lowering the temperature, which only very slightly seems to help.
Does anyone have any idea what might have happened?
RE: Constant PLA oozing at any temperature
Nozzle wear perhaps? Can you swap the nozzle to test? They are consumables. You might also run PID calibration.
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RE: Constant PLA oozing at any temperature
If the filament has been sitting out - not in a sealed bag with desiccant - moisture is possible. Or, if you have replaced the nozzle recently and didn't get the nozzle-heat break seal torqued correctly, you can see excess ooze.
RE: Constant PLA oozing at any temperature
How often should I change the nozzle?
I have printed for about 4~ weeks straight since I owned the thing. Is it nozzle change time?
Additionally, how long does the PLA have to sit out to become unstable? I think my PLA has sat out about ~2 weeks
RE: Constant PLA oozing at any temperature
Though I should specify as well, it's leaking directly out of the nozzle tip. Basically once the nozzle hits about ~190, the PLA starts to leak out of the nozzle. It's a pretty steady rate, not a HUGE amount but enough to be unable to print pretty much anything because it will leave a blob.
I have attempted cold pulling 3x and poking a bit inside with an acupuncture needle to ensure there is not a jam.
RE: Constant PLA oozing at any temperature
Though I should specify as well, it's leaking directly out of the nozzle tip. Basically once the nozzle hits about ~190, the PLA starts to leak out of the nozzle. It's a pretty steady rate, not a HUGE amount but enough to be unable to print pretty much anything because it will leave a blob.
I have attempted cold pulling 3x and poking a bit inside with an acupuncture needle to ensure there is not a jam.
RE: Constant PLA oozing at any temperature
I can let my printer sit at 185c for minutes and not have a drop of ooze. I recently used up all my remnant PLA building some wire spools, and some of it was kept in simple plastic bags for months without desiccant and that filament was a bit ooze prone. And other bags had desiccant and was also oozed a bit more than usual. But I was printing at 210c ... at 185c, no ooze.
How long to leave filament out depends on humidity. My room is typically under 35% in summer, and under 20% in winter. I leave filament out for a week or so if I am printing daily. But if the printer sits for a few days, I'll put the filament away in a zip lock bag with desiccant.
Some folk report fizzing and popping filament after a few days when humidity is above 60-70%, and they resort to filament dryers.
RE: Constant PLA oozing at any temperature
Tried different filament, that is also oozing out of the nozzle.
Tried to re-calibrate, that also did not fix the issue. I ordered a nozzle..hopefully that will resolve it.
Basically as soon as the printer heats up to about 190, it will start to leak a slow, steady stream of filament. It makes all prints eventaully fail due to a blob.
RE: Constant PLA oozing at any temperature
sounds like a bad thermister, the block is getting much hotter than the thermister is indicating. could be a loose grub screw on the thermister or a failing thermister
RE: Constant PLA oozing at any temperature
Take a clip of some sort, clamp it on the filament just above the extruder so filament CAN'T move into the extruder. Does the nozzle keep dripping?
RE: Constant PLA oozing at any temperature
Basically, when filament is loaded, a certain amount of filament will leak out of the nozzle, until it appears that there is no more filament in the extruder to leak out the nozzle.
When you say loose thermistor grub screw, which screw, specifically, are we talking about here?
RE: Constant PLA oozing at any temperature
Here's a video I took of the issue. You can see the issue occuring mostly after 0:30 mark.
RE: Constant PLA oozing at any temperature
How is that screw even adjusted?
Thanks for all the efforts trying to help, by the way.
RE: Constant PLA oozing at any temperature
just should be snug ( not loose)
RE: Constant PLA oozing at any temperature
I do have a nozzle on the way. Some people mentioned the nozzle may be the issue. Is it truly possible the nozzle would cause this odd leak?
I do not feel the thermistor may be the issue if the issue is temperature related, because while doing a cold pull I can feel myself struggling to get the PLA through the extruder at around 170-180, which appears to be normal.
RE: Constant PLA oozing at any temperature
Cold pulls are done between 25c and less than 90c ... whatever you are doing that requires 180c is not a cold pull. And a nozzle will NOT cause the printer to ooze filament.
RE: Constant PLA oozing at any temperature
I'm following the instructions at Prusa's website,
https://help.prusa3d.com/article/lnbcnhg76k-cold-pull
It says "
- Continue manually pushing the filament down until the temperature is too low for it to melt and come out (around 170 °C for PLA). The nozzle has to be filled for the cold pull to be successful."
This is how I know my temperature readings seem to be correct, I think, because right about 175~180, it gets really hard to push through, then impossible after.
RE: Constant PLA oozing at any temperature
[...] It says "
- Continue manually pushing the filament down until the temperature is too low for it to melt and come out (around 170 °C for PLA). The nozzle has to be filled for the cold pull to be successful."
This is how I know my temperature readings seem to be correct, I think, because right about 175~180, it gets really hard to push through, then impossible after.
You're doing it right (though I confess I often just feed cleaning filament in until it runs clear).
To answer your previous question: There's no one time for a nozzle to go bad. So much depends on what and how you've been printing. Having a spare will never hurt. I'd definitely do the PID calibration since it's so little work to do. Are you using one specific brand of filament. Rigid.ink stuff seems to melt at very low temperatures compared to others, although it's very nice stuff.
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He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan