Universal Spool Holder - Skateboard Wheel

thingiverse

The antecedent design, with a single bearing, created an unsatisfying rotation where the spool would sometimes rub on the shaft and cause the filament to jerk. I took the same geometry for the spool interface and adapted it for use with skateboard bearings. Print this and get yourself a set of [Bones Reds](https://www.amazon.com/dp/B0798WGCB1/ref=cm_sw_em_r_mt_dp_Y6K58XG0AJR4J196TN2D) or similar and you'll have an incredibly smooth spool holder. ## Thread Rod Size Note that this is design for 5/16" threaded rod and nuts. It might work with 8mm metric but I did not try this. ## Tensioning Knobs I included two knobs. Both have an end profile designed to interface with the skate bearings without rubbing on the moving ring. One has a deeper profile to allow room for fingers when operating. The other is low-profile which you can use to save space in your setup. Note that the function of these knobs is two-fold; first, they simply capture the spool holders allowing for variable width spools and allowing the spool to be positioned along a section of threaded rod. The second function is to dampen the bearings. This is important to prevent your spool from oscillating as filament is pulled or, worse, unspooling half a role of PET onto the floor after one good tug. ## Note on Skateboard Bearings Some skateboards are designed to go fast and use expensive bearings with low friction. This isn't what you want for your spool holder. Without some friction the rolling action will not be damp enough and it could effect your print or cause your spool to feed out a huge amount of filament with the slightest tug. I'd stick to inexpensive bearings designed for street skating and stay away from expensive bearings for downhill boards. The [Bones Reds](https://www.amazon.com/dp/B0798WGCB1/ref=cm_sw_em_r_mt_dp_Y6K58XG0AJR4J196TN2D) I used are somewhat damp on their own and a little bit of tension with the big knobs in my design can control this property nicely.