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
Y'know just in general I really strongly recommend going all-metal or better bimetallic on your hot end? It cleared up so many problems for me. The Ender 3-series hotends really aren't bad if you just back that PTFE up a bit.
I like this one (no affiliation other than I bought one) quite a lot, and I got it on sale so it was cheaper than the current price. But even at the current price I'd definitely say it's still worth it.