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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

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

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,

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.

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

one link from user tbird:
www.fuellessflight.com/windturbine.htm

A generator solution could be to replicate the
www.geminielectricmotor.com

S
  dL

thanks lancaIV, Gemini is too much for me for now,  is there another simple generator howto that you could recommend?.

thanks

Why not just build your own generator?
its not that hard. and there good at low rpm too.

argona369 can you point me to one that will work for my project?. and simpl to make.

thanks

Check out otherpower, they have some good designs there.
(there are lots of other sites too)
The Twin brake rotor radial design seems popular, and the newest.
Also rewinding Pm alternators and such. You can pretty much even use a DC motor,
Though its not very good because it has brushes that wear out the commuter. Also a straight car alternator is not
good either as it generates the needed magnetic field with a coil instead of having magnets.

Lots of ways to go,
Heck , this guy even made one out of wood.
http://www.otherpower.com/woodmill.html

Or, maybe for the latest designs and help ,post up on their message board.

Right now , I?m helping a friend build a linear fresnel solar PV
for way up north. We also might be doing a wind turbine,
But a prop one, which is better than a savonius I think.
  I?ll probably go with the brake rotor design.

I?d start here,
http://www.otherpower.com/otherpower_wind.html
And here,
http://www.otherpower.com/otherpower_wind_alternators.html

hope that helps.

@avr3

Check this post for a generator recomendation.
http://www.google.com/url?sa=t&client=pub-2734280293205008&sigafs=9MMmaVuXZs6964HO&flav=0000&ct=cres&cd=4&url=http%3A%2F%2Fwww.overunity.com%2Findex.php%3Ftopic%3D3270.0%3Bwap2&ei=3pgaR7PsBImGjAHj9PyfAg&usg=AFQjCNHmKB_dLTmXvoxjVAy4CM-9u2rJAg

thanks guys, the brake gen seams to be the most common used. but the washer machine looks like it has more power output, is it any good with low rpm?

thanks

Hello avr3,
some alternator ideas :
http://www.compkarori.com/dynamo/
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=US4233532&F=0
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=US4318019&F=0

guys, i have not decided on the kind of generator, i need one that works on low RPM. at the mean time i am building another improved version...

take a look

ok i have moded the design a bit and got a better result, here is a jpeg and a small movie.

note that they are only few feet of the ground.

http://www.youtube.com/watch?v=SvQ7qDLV18U
.

i need  help regarding the gearing system that i need, if someone can time the cycle and tell me if i need 5:1,10:1 or 15:1 gea ratio?!!

i am still a biggener and following my own style and with your help guys.

i dont think it is going to spin more than 4rpm per secound!!?? i am not really sure how to messure how fast it is going sitting on the groung like this.

any way please help me decid an the gear system and the best style of generator, i have read the above info you give me and all is good but i think there is still one
out there better for me....will see

Cool, now I can see your ?gear pump? design.
Very original. Might even work great.
Maybe a chain drive?

ok, belt is too mutch slip, direct drive and not enough rpm. most are suggesting chain drive and that was my first thought, so i will focus on the chain drive.

the generator is the trick,

i was thinking of this idea!, waht if i build another wind gen and place it on top the other one but it will spin in the opposite dirction

ad if one run the stator and the other will run the rotor then i will double my rpm just like that, i will draw a design to see what i mean later.
anyway this thing spinn like crazy close to the ground! imagine if on top a roof !!??.  it took me few designs to get it right with the blades and center wieght ratio, so it was a bit of a money hole but when it is done the real thing should not cost more than couble of hundreds.

i will post the next step witch is the gear. please post your thoughts. i am hoping to do this and post my plans for all to try.

regards

avr3