This remix adds spokes and a central axis to the minimalist buffer and removes the lip on the outer rim so that the spool never touches the plastic but it still keeps the filament from unwinding from the spool. TPU does not roll back that nicely, but it can't get tangled at least and can't tangle with other filament in the same box. 

10.06.24: I added the pins for Das Filament (800g) and Prusament (1000g) spools that I am using. They should be working for other spools with the same dimensions.