Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:3968151.

This is a remix of part of this design. The original A_B frame is meant to be screwed on an aluminum extrusion frame or an enclosure, making it unstable for stand-alone usage. It's also pretty difficult to print on filaments that aren't PLA (I struggled to print an usable version on PETG).

This is the 5th iteration of the stand-alone A_B frame I designed myself, it allows the usage of the original holders on a tabletop or inside a dry box. I strongly recommend using it with the bearing version of the spool shaft from the original thing, the spools rolls smoothly and without resistance.