V2 has superseded this design.
https://www.printables.com/model/844412-rack-it-1000kg-spool-holder-v2
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This design is for the Bunnings Rack It 1000KG shelving system.
https://www.bunnings.com.au/brands/r/rack-it
The spool holder will hold 6 filament spools for easy swapping in and out.
Design can be mirrored for the opposite side.
You will require 2x 600mm M8 rods, I purchased the one linked below and cut it into two for my rails.
https://www.bunnings.com.au/macsim-m8-x-1-2m-hot-dipped-galvanised-threaded-rod_p2410295
I used AndrewAggenstein Fila_Role.stl with 608 bearings for the spool rollers.
https://www.thingiverse.com/thing:4778885/files
Once printed I over-screwed the rods into one side, then screwed them back into the other bracket, being careful to keep both plates parallel to each other.
The author remixed this model.
Utilised the mounting system from this design.