Turbines have awesome power in a small package. This one spins up to 60,000 rpm using the airflow of a standard vacuum cleaner, sounds like a 747 taking off, produces amazing power, and sucks up its own dust! This is an opportunity for someone to make a successful product. I have no commercial interest, and would be delighted if anybody developed it further. A good start would be to source a batch of shafts and spacers for people to experiment with. The spinning top is an simpler project, also there is a small hand-held turbine rotor just for fun.Warning - High rpm - USE EYE PROTECTION AT ALL TIMES To have some fun right now, make the hand-held rotor, use a 4mm bolt or nail, and make magic whizzing noises with your vacuum cleaner. The Spinning Top requires a few bits, but no special machining. DO NOT PRINT the body, I purchased a 2" plastic wheel which has the strength for the high rpm. The shaft is 5mm all-thread or bolt, and the socket is a 5mm Philips head screw drilled out. Top Video http://www.youtube.com/watch?v=6Wc73shHrsY Turbine Tool http://www.youtube.com/watch?v=SuztgGhTRg0 The Turbine Dremel-type tool is awesome, but does require proper bearings and an accurate machined shaft. High speed requires excellent engineering. The bearings are 696, 6x15x5, from bearing shop, Ebay, or vxb.com, check the rpm rating for the type you find. The shaft could be just 6mm rod if you don't want power out, but the Dremel style tool head requires a tricky 9/32" x 40tpi thread for the nut, or may be metric for other brands. The design is a 2-stage axial turbine, with 2 stators to twist the air, and 2 rotors to deliver the power. I considered a radial inflow design like the auto turbo, but the axial one is more compact. The speed and power is amazing. It was only when doing the video that I realised it was doing nearly twice the speed of my Dremel, really scary! The rotor and blade design is my first attempt, it is powerful enough without any optimisation. I should change the pitch of the rotors to reduce the speed to match other rotary tools. The tool is great for cutting composites, as most of the dust is sucked up, instead of the Dremel's cooling fan which blows it everywhere including inside my goggles. This could be an excellent production tool, laser-cut metal rotors would be good. PLA is good for this prototype, but cannot stand the elevated temperature of extended use.