Filament climbing the outside of the nozzle

[aidtopia 0]

I've been printing successfully for almost a year, but now I'm having trouble getting the bead of filament to adhere to the build plate. The filament seems to be coming out thinner than normal, and it immediately curls up and adheres to the outside of the nozzle.

I have tried each of the following, multiple times:

1. Re-leveling the build plate. This includes attempts to position the nozzle both closer to the build plate (by adjusting until there's more resistance than usual when sliding a sheet of paper between the nozzle and the build plate) and to position it farther from the build plate (by adjusting the screws just shy of the resistance point).

2. Going atomic to make sure the nozzle has no obstructions--the cone comes out very clean and well-formed.

3. Slowing down the speed for the first layer.

4. Changing filament (from and older spool to a fresh one).

5. Cleaning the build plate and re-applying fresh glue stick (as I've done successfully many times in the past).

Same problem in every case. The filament comes out thin and defies gravity, preferring to curl up and cling to the nozzle rather than be smooshed against the build plate.

Suggestions? I'm at my wit's end.

[Nicolinux 288]

Hi, and welcome to the forum!

If you have the Olsson Block, did you change a completely new nozzle?

[aidtopia 0]

No Olsson block.

I seem to have found the problem and the solution. Once there's a bit of PLA on the outside of the nozzle, the new PLA really, really wants to join to it.

I solved the problem by cranking the nozzle temp up to 260C for a few minutes to melt the plastic that clung to the outside and tugging at the drips with some needle nose pliers, being careful not to nick the nozzle with the tool. This removed most of the PLA that had adhered to the nozzle and now the newly extruded filament moves down as gravity would seem to dictate.

Of course, during the Atomic method, you set the temp up to 260C, but it was never at the temp for very long, so it wasn't enough to melt off the bit that clung to the outside of the nozzle.

[ultiarjan 1,223]

For PLA I never use 260 to do an atomic. More like 230. That's really enough imho. I would advise against 260 as you run the risk of overheating the pla and making things worse iso better....

[geert_2 557]

After each print, when I am in the neighbourhood and I hear the printer finishing, I immediately clean the outside of the nozzle while still hot, by using a thick (!) tissue. Also when doing an atomic method, I often clean the outside too.

I refer to this as "wiping its poop hole", to avoid confusion with cleaning the inside of the nozzle (atomic method).

This also gives cleaner prints, since there is no brown residu sagging and leaking onto the next prints.

[Nicolinux 288]

I do the same, although I don't like your metaphor. How about "wiping the schnozzle"?

[neotko 1,417]

To clean the outside faster lately I heat the nozzle to 90-100C while the bed it's warming up and then I drag a filament peace, the brown goo sticks to it and doesn't leave residue.

[DidierKlein 729]

You can do that also when you do an atomic with some piece of filament squish it against your hot nozzle to make it melt against the exterior of it, and when it's hard enough just pull it like you do for the atomic to take all the junk away and have a nice clean nozzle

@aidtopia have you checked your teflon isolator? It might be damaged and adding some friction to the filament which might cause the underextrusion?

[ultiarjan 1,223]

I refer to this as "wiping its poop hole"

bllaahh I hope this will not become the popular name for this.... hope someone come's up with something else

Think I'll call it "outside atomic" for now

[aidtopia 0]

Thanks for all the replies.

I don't think there's a problem with the teflon isolator. The under-extrusion seemed to be related to the gunk clinging to the nozzle itself. Now that it's cleaned up, I'm getting good prints again.

Next time I go atomic, I'll try a lower temp.