Since I have a wooden beam in my room and it's perfect for storing filament there, I designed a spool holder for it because most of the online ones are only available for the wall. I use a wooden stick with a diameter of 22mm. The radius on the holder itself is 23mm. I wouldn't make the rod too long because the wood would bend. If you want it to be longer, you can place a third holder in the middle as support.

I use PLA+ from SUNLU, but normal PLA should also work.

I print it on my Bambu Lab P1S with the standard settings and the Generic PLA filament profile.

No supports are needed.

I hope there are a few who can use this design.
Greetings