yesterday I had some spare time:
piece of plywood skateboard "truck" (axle, axle mount, bearings, wheel=hub)7 Compact disks 10 bolts + nuts 16 washers
4 bolts +nuts for holding the truck to the plywood
stacked CD's, cut 4 holes on outer edge (for bolts, to hold CD's together)2 holes on inner edge (connection to hub) 5 CD's need their inner hold widened.
put it together. blew on it with the compressor. approx 4000 RPM
Ok, it wobbles. badly.
today, I went ahead and remade the CD's, drilling them closer to precise.
approx 8000 RPM12V no load (with a 6volt motor) 6V with load, 2amps output.
So, I decided to add ONE nozzle:1/8" inner diameter aluminum tubing 2X4 wood supports
approx 10,000 RPM8volts, 2 amps loaded
measured with digital multimeter.