Summary

table top spool holder
uses a M10 threaded rod, 2 x M10 washer and 3 x M10 nuts
the 48mm 'bearing' that is included, fits on a rrw 50mm spool
also added a 52mm 'bearing' for larger spools

Instructions

print table stand and 2 spool bearings of the same size
turn 2 nuts on the M10 rod on one end and tighten them so that the rod is a couple of mm from the table when inserted in the table stand (25-29mm)
put the m10 washer between the lower M10 nut and the top of the table stand
put a washer and one spool bearing on top of the 2 nuts
put the spool on top of the bearing
put the other spool bearing on top of the spool and tighten the spool and the holders with a M10 nut
in case that the threaded rod doesn't move freely in the 10mm hole of the table stand, you can clean the 10mm hole with a drill

Spool Holder