This is a design I made to re-use my empty filament spools instead of printing a refill spool.
I have now made a couple dozen of these and are working great. the spool holder opening for this is 42.5mm ( it fits over the creality and geeetech spool holder nut easily )this should fit any spool with a center hole that measures 54mm and is a bout 65mm wide.
This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/fRakU2RTAhY
what ever you like
3 top layers
3 bottom layers
infill is what ever you can get away with while still getting good layers
you will need
install refill spool (ziptie out!)
push on the second side of the spool plate
slide clamp bolt through center of spool
tighten down nut (DO not over tighten, just snug is perfect!!) cut zipties and your ready to print
cut out center of old spool with a hacksaw, ( DO NOT USE A KNIFE!!!) ask me how i came to that decision