This is my second crack at a response to Patrick, the computer ate the last one.
Patrick, please provide a bit more info on the generator you plan on using. How many rpm does it need to start developing the voltage you need? How much power are you trying for? What is the average wind speed (and max wind speed) at your site?
My experience in building as many as 600 small turbines, indicates that a two bladed prop will perform admirably if well designed and carefully carved. A three or four bladed prop is much more difficult to make and will give a very slight improvement in early startup, and may or may not prescess a little more slowly.
If you google NACA 0010, you will find a foil shape, use this shape (half only) for the downwind side of the blade, the upwind side can be flat. Carve as much angle into the prop near the hub as poss, radiating (wash or run out) to an angle at the tip that is almost perpendicular to the wind. The actual angle can be calced based on the parameters of your site and generator.
Hope this gets through this time,
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