This is a remix from the user guillaumeguiral. I liked the look of his design but needed something that could be scaled as needed.

Adapted for 21mm OD tubes/pipes/rods

Designed to lock the stacks with an m5 cylinder head screw (12mm should work, else 14mm is fine) and corresponding t-nut. Might add a normal nut version later if needed.

As usual beware of tolerances, Print the "Filament Spool TopMid STL" for a test fit and scale accordingly, you only really need a few layers to check tolerances. My advice do a test print at 101 or 102%, for me 103% gives me a tight fit

Patch :

• Updated Top Rack as it didn't have the right thickness for a clean look, Should work as intended now