I like you method. I am using the core of a vacuum cleaner engine from an abandoned vacuum for my bearings, shaft, flywheel, and mounting brackets, I have a spare mouse, so all I need now is the encoding wheel and a knob. Did you use the "barrel" style encoding wheel or a disk? Now that I think about it, a cd-r would make a great encoding disc... it's big and sturdy, but do you think it might be too big? Or could I just make the spokes wider?