Fun article at OtherPower.
This is a re-print from a 2002 article where they build a working wind turbine in one day using cheap surplus parts. Not too shabby a performance either -- with a 25 MPH wind, it puts out 60 watts using a 4' diameter homebuilt turbine propeller.
Cute hack: The stator requires some iron pole pieces to complete the magnetic circuitry and to direct the magnetic field from the rotor into the stator windings.
Not having the iron for the pole pieces and not wanting to take the time to fab something up (the entire project took one day after all), they put one of the rotor magnets into a plastic bag and dragged it around their yard. A good percentage of the Earths crust is composed of Magnetite Sand and they took the sand that was attracted to the magnet, mixed it in with some epoxy and glued the resulting putty into the stator compartments.
Clever!
