3D Printer Spool Hub / Holder

Here's yet another design for a 3D Printer Spool Hub / Holder. This design uses a piece of 8 mm threaded rod, two 0608 bearings, a couple of 8 mm nuts, and two more 8 mm nuts or in my case two 8 mm acorn nuts for a more polished look. The two 8 mm nuts are press fit into the thumb-wheels which are used to keep the spool hubs in place. Don't tighten the thumb-wheels too tight otherwise the spool will not move freely. The hubs have adhesion pads to keep the arms from curling during printing and it has a small spacer inside to support the bearing cavity. The pads snap off and the bearing cavity support can be removed with an Xacto knife.