About this 3D model
I found that the REPRAP spool holder I purchased did not work with the supplied Prusa filament spool so I created a width plate. It is currently set up for 75mm-95mm wide spools (2-15/16" to 3-11/16"). While I was at it I improved the tolerances so that it retains the nut and will not allow it to spin (unlike the original). Link to original spool holder