Anti tumbleweed Prusa Spool PET attachment

I made the https://www.printables.com/model/460950-compact-pet-filament-machine and it works really well. The PET strands however are very rigid, and if rolled on a small spool it will eject back like a spring, creating a mess and making it impossible to do any printing. So I came up with these clamps to keep the filament i place on the original Prusa spool. The filament will then release slowly as the spool turns. You need 4 of them, and maybe some long strips if you want to adjust the clamping effect. I made these with PLA, but I guess any hard material will do. You may need to disassemble the spool to align the holes.