BCN3D Sigma Bowden Creep Fixer

thingiverse

Some BCN3D Sigmas are plagued by bowden tube creep - there are already numerous shims that address this issue due to retraction, but on my sigma it also occurred because of rotation of the bowden tube in its fitting. This straightforward modification fixes both problems. Simply print both files, heat up the extruder, remove the bowden tube, loosen the extruder screws, slide in the bowden holder, insert the bowden tube, retighten the extruder screws, secure a cable tie as tightly as possible, and slide in the anti-backlash shim. To extract the tube from the extruder, simply remove the shim and loosen the extruder screws slightly. You should be able to pull out the tube with some force (holding the bowden fitting's collar down) and then slide the holder out from under the extruder screws. I have a small redesign in mind that will make removal easier, but for now it seems fine as is. Print Settings Printer: BCN3D Sigma Rafts: No Supports: No Resolution: 0.1mm Infill: More is better - I'm using about 75% Notes: It probably prints well in 0.2mm too, but I haven't tried this yet. Note that the shim is 1.1mm high, so it'll come out either a bit too tall or too short, but it should still work just fine. I printed this in PLA and it broke very quickly. I've now updated the design with thicker walls, so hopefully it'll stay intact in PLA, but this part is best printed in polycarbonate.