Two bearing spool holder

This is a low-friction spool holder.  It uses two of 608ZZ bearings and a length of 8mm threaded rod to hold a cylinder on which the spool rests, that has ramped ends so the spool doesn't fall off.

The mount can hold spools of 32mm hole or larger, and up to 71mm wide.

The mounting shown in white is a simple nut for my Ender 3's 30mm mounting hole.  It uses the M30 (?) nut from the original mount.

Bill of Materials:

• 8mm threaded rod, 110mm long approximately.
• 2 of 608ZZ bearings (22mm by 7mm, with 8mm hole). 
• 2 of M8 Nyloc nuts.
• The 30M nut from the original mount (Ender 3, Balco, other brands?)

Assembly is simple. Put the tube in the spool holder, thread the M8 rod through it and the M30 mount, add the bearings either end, and tighten the M8 nuts to each end. Don't overtighten or it won't rotate freely.  (The tube was meant to prevent overtightening, but it's not very effective).

If your bearings are a different size from the normal skateboard ones or you use wider spools, the freecad source is included so you can remix it for your sizes.

Print it on its end in any material, with supports from the build plate only, for the lower bearing cavity.