openion needed on windmill design

[avr3]

please review the design ideas for the blades mounted on a vertical axis windmill.

i am going to build one no matter what, but first i need to see if you can help on deciding the best blade design for less drag from the back .

these rendering are posed looking from the top of the windmill.

the blades are placed insde 2 planks of wood 30" apart so the blad will be 30" high and 40" long not including curve.

i hope i get feed back on this.

regrads

[avr3]

here is the one i put together, too much drag on the back of the blade, so before i start haking at it if any one has great ideas to mod the
existing windmill that would be great.

thanks

[argona369]

Look up
Savonius Rotor
http://www.technologyforthepoor.com/WindEnergy/WindEnergy.htm

Its ironic there sometimes made from oil drums.

also,
http://www.otherpower.com/otherpower_links.html
http://www.otherpower.com

Cliff,

[Localjoe]

Use Phi, I found a few instruct ables that showed the natural golden curve is the best for this design i would recommend sheet aluminum cut 4 pieces a little bigger than the radius of a large wooden disc, you will need 2.  Draw the curve 4 times from the cardinal points on both pieces  and dremel groves along that not too wide tho, just enough to get the aluminum sheet in. You should be able to fit them in your grove and bend to shape easily, at this point you might have to cut the aluminum pieces to fit better.  You could put an alternator directly on the bottom of this but I would recommend gearing it to drive a flywheel with magnets on that, prolly get better speed out of it for power generation.

[avr3]

thanks guys, i will draw what you suggested withe 4 blades wedged in between.  now waht is the best alternator or generator to have on this? home made?

thanks