Sticky residue buildup in PTFE Tube - eviltoast

Trying to reduce the amount of constant maintenance the my ender 3 printers require and one of the biggest issues i’m having is a buildup of sticky residue inside the ptfe tube inside the hotend/ptfe tube. It’s not leaking as i visually inspect before cleaning and i can see where the tube connects and there’s a clear line and no visible signs of leakage. Usually some rubbing alcohol and a scrub brush will fix the issue for about 100hours of print time before needing to clean it again.

I’m wondering if i might need to reduce the flow rate on the printers or maybe i’m missing something. Running this with a direct drive extruder so the ptfe tube is pretty short and since the residue is building up inside the heater and nozzle too i don’t think that’s the issue.

Things i have tried:

  • less heat printing at 200 instead of 205 - marginal / no difference
  • printing speed turned down to 20mm/s - it takes longer for the buildup to become an issue but it also takes as long for the prints to complete
  • lowered retraction distance i thought the high retraction distance might be causing issues, while it made it better now i have stringing to deal with

EDIT: Added requested Photos -> https://imgur.com/a/XPKGI7D

  • rambos@lemmy.world
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    1 year ago

    Yeah all metal is proper way of doing it , even tho lot of people had great success with stock hot end. Im confused because it looks like OP have all metal

    • Uranium 🟩@sh.itjust.works
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      1 year ago

      Am I being silly?

      To me it looks like the stock ender 3 V1 hot end that OP is using, which I didn’t think was all metal, then again I don’t know what constitutes all metal…

      • rambos@lemmy.world
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        1 year ago

        In all metal hotend ptfe should not go all the way to the nozzle. Nozzle should be tightened against the heat break to stop heat from going upwards. Ptfe just guides the filament, upper area is not heated and therefore cant leak unlike ender style hot end that requires pressure between ptfe tube and heated nozzle.