Quick change spoolholder for K8200 / 3Drag or other frame printers

Quick change spool holder for designed for K8200 / 3Drag, however might fit other frame style printers as well.
To change a spool, loosen one of the thumbscrews/knobs and move the pilar aside and replace the spool move the pilars together and retighten the knob.
Note this design needs a spool centre; I used this one https://www.thingiverse.com/thing:360648, but any other will also work.

The bottom part fits neatly on the K8200 / 3Drag frame, and positions a M5 square nut for the knob.
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