Filament Coil Holder for Lulzbot Mini (remix)

thingiverse

The stock filament holder for the Lulzbot Mini is basically a printed stick, and it works fine most of the time. But I had to replace it with something a little better after I encountered a couple of long overnight print jobs where the printer struggled to overcome the friction between the spool and the stock coil holder. I decided to create a more reliable setup by using the spool centers and knob without modification from this project: http://www.thingiverse.com/thing:219667. The skate bearings fit perfectly into place with a nice snug tap-in sort of feel. I had to use epoxy on a 5/16" nut for the knob, but it was easy to attach. I printed the knob pointy side down with a brim, and the wide end came out beautifully. At first, I was skeptical that it would print okay, but it turned out awesome. Then, I made a bracket to replace the stock holder, which holds a 5/16" carriage bolt. The bracket has a little extra feature - a square hole on the backside that keeps the bolt in place while still allowing for easy removal. I used an 8" carriage bolt, but you could use a shorter one like 7.5". You'll need to bore the bolt's hole in the bracket most likely using a 5/16" bit. The square hole on the backside should be snug enough to hold the bolt without issues, and when tightened down, it keeps the entire assembly together. The spool centers come with skate bearings, but you could use epoxy or create some nylon washers if you don't have bearings lying around. This would allow for just the right amount of tension that prevents unspooling while still allowing for smooth printing. I've included the source files in FreeCAD's native file format, and there's also a separate hole pattern available if you want to make your own filament support from scratch.