Anycubic i3 Mega extruder for flex or TPU filament

thingiverse

Yet another extruder for printing flexible filament on the Anycubic i3 Mega. Designed to be used with 4mm PTFE tube, only need about 20-25mm. Reuses the original silver collet. Install the collet with an M6 nut or my replacement printable insert nut, insert the PTFE until it stops, and then trim it to fit using a sharp razor. I also used a tapered diamond file to open up the end of the PTFE tube to a cone shape to help guide the filament during loading, although that step isn't strictly necessary. You'll see there is also PTFE tubing below the feed gear as well - this is only for convenience during filament loading - same with the nut that screws into the lower portion of the extruder. The nut has a funnel shape which helps guide the filament into the proper location for loading - I was constantly having trouble finding the lower hole and then getting the filament loaded to the right spot. Having the lower nut and a section of PTFE tube helps guide the filament to the right spot on the gear. With this in place, I push in the filament until it stops, and then turn the extruder with my [extruder knob](https://www.thingiverse.com/thing:3777870) (pictured in the last photo) to load it the rest of the way. If you don't want to bother with the PTFE tubing in the bottom, I've got a variant of the lower plug which has a guide tube that replaces the PTFE.