Guide funnel for loading filament into PTFE tubing

Simple funnel that presses onto the end of a 4mm PTFE tube so it's much, much easier to load 1.75mm filament into the tube. I've been using this for years anywhere that the printer has a PTFE tube as the inlet for filament and it makes life much easier when you're feeding in new filament.

Printing is simple, print the large end of the funnel face down. No supports needed. I have done a fine layer height (sub 0.1mm) to get a smoother internal wall but even at 0.2mm the filament doesn't get stuck while feeding it in, so layer height is pretty much up to you.

I've also printed this on my MSLA printer (Elegoo Mars 2 Pro) and that works as well with very smooth walls, but I don't find it necessary.