Filament load unable to perform "purge" stage after removal of blockage
About 6 hours into a 23 hour [PVB] print, I had the filament break off just below the cogs in my MK4. I removed the nozzle, heated it and was able to pull out the stuck filament; afterwards I could push a 0.33 mm guitar string all the way through the nozzle without issue.
However, with the nozzle returned to the printer, when I try to load new filament it begins to load but at the "purge" stage of loading, the filament is not pulled any further into the printer, no plastic emerges from the nozzle.
I've tried increasing the nozzle temperature up to 285 C during loading; that didn't help. I don't hear/feel any noise from the cogs against the filament (and the filament doesn't look burred when it is removed), so I guess it is being gripped.
Presumably there is still some residue high up in the nozzle that needs removing, somehow. Does anyone have any suggestions as to how I clean the nozzle that far up? I guess since this is PVB I could try soaking it in alcohol...?
Best Answer by JP Guitars:
I've had them glowing red and working fine afterwards
RE: Filament load unable to perform "purge" stage after removal of blockage
Heat the whole nozzle including the tube with a blow torch or over a gas cooker to burn out what ever is stuck in there
RE: Filament load unable to perform "purge" stage after removal of blockage
OK, though I'll be afraid of going too far and damaging something through overheating: is there a significant danger of that?
RE: Filament load unable to perform "purge" stage after removal of blockage
I suppose it's useless to me as it is, so no loss if I do damage it.
RE: Filament load unable to perform "purge" stage after removal of blockage
I've had them glowing red and working fine afterwards
RE: Filament load unable to perform "purge" stage after removal of blockage
OK blow torch it is!
RE: Filament load unable to perform "purge" stage after removal of blockage
To confirm: this absolutely did the trick. 5 minutes with a blow-torch pointed at the middle/upper part of the nozzle, until smoke and a small amount of plastic bubbled out of the end, then played over the whole of the nozzle until the plastic slowly carbonised, did the trick. I am now in business again :-).
RE: Filament load unable to perform "purge" stage after removal of blockage
Good stuff.