I already closed the disc, as in, I put the other side on already... I would be a pain to take it off again to show you the insides.

Oh, and I think I tied this wheel up with fishing line. I used zip ties for the rear.

Nothing is attaching the edge of the disk to the rims. Although, I was thinking I could put some plasticine around the edge to stop the wind from getting in. Or, if I wanted it to be a permanent disc, I could just use some rubber cement.