I am considering building one myself. My plan is to construct a plywood box with a slightly tilted top that has three roller blade wheels in it (in the same orientation as a bicycle wheel). A 1.5 inch plywood disc will rotate on top. Two additional wheels (rotating horizontally like a top) will keep the disc from slipping off of the three vertical wheels.
by Stephen Meschke, in response to this post 2015-09-05 00:10:40