Notifications
Clear all

Filament accumulating on nozzle  

  RSS
Allectus
(@allectus)
Member
Filament accumulating on nozzle

I have filament accumulating on the nozzle during the course of printing.  It appears as a little ball that grows in size over time before eventually falling off and starting again. The main problem is that these little poops can end up anywhere, including attaching to the rest of the print an marring the surface.

This is a gradual process where it seems some portion of the extruded material is just collecting on the nozzle as it goes--this is NOT a result of the nozzle crashing into something and ripping it off the bed (in the pictures you'll see a circle where near the wipe tower where it **looks** like that's what happened, but there one of the poops attached itself to that piece on like the second layer, I tried to pull it off, lost adhesion, and elected to just cancel the part).  The filament is dry (I'm running it directly out of a drybox) and I'm usuing nothing but prusament with default profiles (0.2mm structural).  It's happening across basically all of my 5 print heads.

I've run through multiple calibration steps and nothing has helped--I get a random poop dropped on the bed roughly hourly and it's just luck of the draw whether or not it ruins something.  In the pics you can see the poops scattered over the bed as well as adhering to various parts of the job.

Pics show poops scattered on the bed (and attached to printed object 🙁 ) as well as what it looks like forming on the nozzle.

Any ideas?

 

Posted : 10/05/2025 4:33 pm
Jim Lahey
(@jim-lahey)
Member
RE: Filament accumulating on nozzle

Hate to say it but there do seem to be signs of moist filament

Posted : 11/05/2025 1:24 am
Chris Hill
(@chris-hill)
Honorable Member
RE: Filament accumulating on nozzle

This is most likely a small amount of over extrusion. Reduce the extrusion multiplier for the filament to something like 0.97. In my experience a little bit of under extrusion can be tolerated much better (i.e. I don’t notice it at all) than a little bit of over extrusion, so I tend to use 0.97 for most filaments. 

Posted : 11/05/2025 7:22 am
BaconFase
(@baconfase)
Reputable Member
RE: Filament accumulating on nozzle

Other than your random balls of filament issue it looks like the pressure advance setting for your green filament needs tuning. Should help with the puffed out corners and separated perimeters on the green parts of the cubes.

XL-5T, MK3S MMU3 || Printing with multiple nozzle-sizes: Official Guide, Unofficial || PrusaSlicer Fork || Other advanced slicer tactics || TPU

Posted : 14/05/2025 9:54 pm
Share: