FEEDERBOT I made a filament rack and wanted to share the parts list and diagram so people could make their own. I spent a long while testing with spool sizes from all the usual suspects and this setup seems to work well with all. The 3/4" pvc pipe (actual outer diameter 1" or 27mm) fits the smaller 33mm spools (Octave, MatterHackers) and the larger 52mm spools (MBI, Protoparadigm). One Note: I sell this rack fully assembled and it includes the red threader cap that cleans the filament in some of the photos. Unfortunately since that part is patented I can't share it here. (http://www.feederbot.com)