Simple Yo Yo

This is my second attempt at 3D Modeling. Its a Yo Yo. To assemble: print 2 copies of the sides and 1 of the shafts. The sides each have a 3mm hole in the bottom. The shaft is 3mm in diameter. It should be a snug fit. Then, tie a piece of string around the shaft, wind it up, and Yo Yo away.

Not even sure if this works as I'm very new at 3D modeling and I don't have access to a 3D printer (yet). If you build it, let me know!