Filament Spool Brake (for 806ZZ bearing on Anet Filament holder)

I made the Parametric Filament Spool Hub for 806ZZ bearings (http://www.thingiverse.com/thing:605360), but my bearings rolled so easily that when it start turning i won´t stop until the filament was a mess. Had to create som kind of brake!

I have the Original filament roll holder that came with my Anet A8 (I assume it´s sent with other Anet printers as well). So I made a simple distance on one side (19mm long), and another "brake" part (also 19mm long) that I mount on the other side.
With th