BCN3D Sigma Bowden Creep Fixer

thingiverse

Some BCN3D sigmas suffer from bowden tube creep - there are already a lot of shims that fix this happening due to retraction, but on my sigma it happened additionally because of rotation of the bowden tube in its fitting. This simple mod fixes both issues. Simply print both files, heat up the extruder, remove the bowden tube, loosen the extruder screws, slide in the bowden holder, put the bowden tube in, retighten the extruder screws, add a cable tie as tightly as you can, and slide in the anti-backlash shim. To remove the tube from the extruder, just remove the shim and loosen the extruder screws slightly. You should be able to pull out the tube with a bit of force (holding the bowden fitting's collar down) and then slide the holder out from under the extruder screws. I've got a small redesign in mind that should make removal simpler, but for me it seems fine the way it 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 fine in 0.2mm as well, but I haven't tried this. Note that the shim is 1.1mm in height, so it'll come out either a bit too high or too low, but it should still work 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 whole in PLA, but this is a part best printed in polycarbonate.