I have been experimenting with changing the filament path of my TAZ 6. I’ve been getting snapped filaments from the amount of torque and force brittle filaments like laybrick, laywood, polywood get when they go through the filament tube into the idler.
This is the best solution I have found so far – mount the filament reel on TOP of the machine, not the side. This eliminates the need for a filament guide tube, and the friction that the tube has. ( same problem delta printers have with bowden tubes )
These filament holders are easy to print, use standard 3/4" PVC pipe has the spool holder, and so the job very well. So far, they have fit all the spools I have purchased from Lulzbot, MakerGeeks, HatchBox, and others. When you put a PVC tube in them, they support themselves, but I chose to ziptie mine to the machine and 3D print the tube.