Hi Gator
It all Starts with the Magnets. The more powerfull they are. The more current you will get back. You Then wind your first coil to match your Mags "and" your intended voltage.
The Rotor will made from a mild steel about 1/2" / 12.5mm thick.
Do not try to use Stainless steel, Alumium, or wood.. They will not give you any Flux return. and will give you little to no power.
The problem with steel is the rusting issue. so glueing the mags are a problem. That is why I like to get mags with a hole in them, and use a "STAINLESS" Bolt through them. A Stainless bolt in the Mag does not change the flux pattern.
With the right mags and coils, in 3 phase you should be able to build a single Stator and still get 800 watts.
S. Simon