Filament Spool Holder for box style printers (with Aluminium-Profile)

You can mount this holder to an vertical extrusion at the back of your printer to hold a role of filament. And a second one for the second Extruder. And a third one for the spare-role.

SCAD-file:
You can sutomize nearly everything to fit your preferences and printer-setup.

STL-file:
I used filament-roles that are 9cm wide.
The STL-file fits for 20mm aluminium profiles and M5 screws.

EDIT:
Added a calculation for having the desired wall-thickness in endcone regardless of extreme val