Huge bulp of PETG sticks around the nozzle  

RE: Huge bulp of PETG sticks around the nozzle

You have a first class blob of doom. Search for blob of doom to see how others have dealt with them.

Before doing anything, look at pictures of a clean extruder and note the position of the rather delicate wires that are currently hidden, if you damage them you will have to buy replacement parts as broken wires can't be rejoined.

To remove it:

Raise the nozzle temperature to the printing temperature for the filament in question and allow it to heat for several minutes.

If you are lucky you will be able to prise the blob open - more likely you will need to add heat from outside with a heat gun to aid the softening, sometimes it's worth using a soldering iron to carve chunks off the mass.

Use needle nosed pliers to prise this away; remove it in parts if it won't release the wires.

Once you have the worst removed you decide whether you need to disassemble the extruder to get at all the blob or perhaps you can clean up in situ.

After the cleanup there will be overcooked filament inside the nozzle so at least a purge and probably a cold-pull will be necessary.

Cheerio,

RE:

Thank you a lot in advance.

Soldering iron was already in use, but I need to do that outside. Chemicals were in the air 🙂

OK:

I will give it a try as you described - still not knowing how to figure out if I cut the blob or parts of the extruder.
We have 5 more Minis - so I can take a close look at the *original*.
I will keep you informed.

Many thanks again.
Matt

Problem solved

Thank you so much, Diem.
By searching for the word *blob* I found a very simple solution:
Heating up the Hot-End - more than needed.

If anybody else gets in this trouble - the very most important thing is:
Be patient.

Let the Hot-End heat up.

Half an hour at least.

Don't try to release the bulb while you see that it is able to be moved.

Keep holding on until it almost falls down by itself by gravity.

-----------------
After *re-bulping* there is still some material left - especially on the heater.

Does anybody have a good clue how to take off this material?

Cheers,

Matt

RE:

You can try to gently remove remainders with a metal brush while it is hot.
Or if it is clean enough just wait until it is cool, then disassemble it and use other means to clean it (like a knife/filer) and avoiding cable damage.

Heating up the Hot-End - more than needed.

You now have overcooked filament in the hot end.  Cold pulls will be essential.

Does anybody have a good clue how to take off this material?

As @_kaszpir_ suggested: brushes, blades and probes while hot.

Cheerio,

Problem solved - thanks for the help

_KaszpiR_: The metal brush was the answer. Thank you very much.
Diem: Yes, as you mentioned, I got rid of 99% while the extruder was hot.
_KaszpiR_: Your suggestion of using blades when the extruder has cooled down might surely remove the last 1%.
But being honest: I am to lazy for that job. Thanks anyway 🙂

Problem solved - The MINI is up and running again.

Matt