A Very Cheap Filament Turntable

I made a turntable for my filament with some glass marbles, a piece of cardboard, and an empty CD case. I tried it with a roll of filament less than one pound, it worked fine, but I had to put some weight in the center when the filament is running out. I'm now testing it with a new 5-pound roll, and it's running good so far. Although I'm a little concerned that coils of filaments drops off the turntable sometimes with this 5-pound roll. I think I should have cut the cardboard table bigger. Anywa