RE: Problems unloading filament.. Jamming in PTFE tube
@jakub-kohoutek
Did you drill the tube or the brass part?
The tube, because it was too narrow in the area where the brass fittings are. They are probably too tight.
@steve-4 - I am using the "unload filament" option from the printer's menu that preheats the hotend before it tries to unload it, so it's not a cold unload. But still it didn't work. Many people are facing the blob at the end of filament issue and even though it should have been solved by the 3.0.4 firmware (see the github issue https://github.com/prusa3d/Prusa-Firmware-Buddy/issues/199 ), it's not.
Hi Jacob
The blob at the end of the filament is mainly caused by 'too much space' in the hot end, into which the filament expands when molten.
You need to make sure your 'hot end' and PTFE tube are properly seated together (without gaps), this is the 'grub screw loosening, pushing hot end up and retightening grub screw' thing. There is a PRUSA article on the full process somewhere 😉
S
RE: Problems unloading filament.. Jamming in PTFE tube
@steve-4 - thank you for the tip 😉 I guess you mean this article: https://manual.prusa3d.com/Guide/How+to+change+a+hotend+PTFE+tube+-+MINI/1505?lang=en ? I've already gone through these steps and it didn't help. The blob is not very wide (it has cca 2.1 mm in diameter, not caused by a space between hotend PTFE tube and other parts), but it was still too wide to go through the narrow places in PTFE tube.
RE: Problems unloading filament.. Jamming in PTFE tube
@jakub-kohoutek
Yes buddy, specifically step 9 in that article 😉
S
RE: Problems unloading filament.. Jamming in PTFE tube
I have never encounter the problem while loading and or unloading, but my PLA filament will jam in my PTFE tube when using a .25mm nozzle. With the .4mm nozzle there is no issue with the filament jamming in the tube, but when I'm using .25mm nozzle after 2 hours of print, the infamous clicking noise appear and the filament is jammed into the tube and it is impossible to pull it or push it out...
MK3S with Pursament PLA 215 deg. .25mm nozzle.