non-grinding feeder for Ultimaker

thingiverse

This feeder efficiently handles filament retractions, preventing slipping or grinding issues. It's no longer necessary to use Ultimaker's proprietary 2.85mm filament as it supports 3mm filaments without deformation. Combine this feeder with a stock bowden setup for seamless printing without jamming concerns. However, the OpenSCAD file design requires significant cleanup. The original design faced several problems, including challenging adjustment of gear distance and loose bolts during retractions, which were resolved using Loctite screwlock. Rubber rollers were replaced with knurled steel rollers due to excessive wear; higher shore hardness rubber rollers could also be considered. Spring additions improve contact pressure. Bending issues in the variable part sometimes cause gears to jump over teeth, necessitating a guide on both sides or linear bearings for fixation. The bowden clamp riser's large bore might lead to clinched filament; an aluminum part fixed this issue, but modifying printed parts is another potential solution. For assembly, gather 14 bearings (6x13x5mm) and screws, nuts, and washers in M3, M5, and M6 sizes. Use a bowden clamp from this link: http://www.thingiverse.com/thing:17027. Obtain rubber rollers like these from Pollin (or consider knurled wheels) and cut a M6 thread into the hole. Calibrate your printer for optimal performance, and printing in PLA with 30% infill is recommended. A heatbed helps prevent warping, but it's not strictly necessary. Be cautious of bearing holes that may be too large, as epoxy glue can fill these spaces.