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Just making sure you know that we get different voltages based on what motor you use, but... We have gotten 410 on high, and 340 on low with 5 ohms of resistance.
I was actually thinking about using a solid aerofoil design. Maybe sanding it out of foam? Last year (Physical Science Lab), we got 1600 on high (without any resistance) using cereal box cardboard.

Just curious,

but how's everybody doing so far? like what voltage are you getting with what ohms? I've been using a 10 ohm resistor so I'm expecting my results to be a tad higher than What I'm currently getting.

illusionist wrote:Just making sure you know that we get different voltages based on what motor you use, but... We have gotten 410 on high, and 340 on low with 5 ohms of resistance.
I was actually thinking about using a solid aerofoil design. Maybe sanding it out of foam? Last year (Physical Science Lab), we got 1600 on high (without any resistance) using cereal box cardboard.

how do you make each blade match? I build mine out o a basswood frame with a preset pitch, then cover with tissue, segment by segment. Like how you would make a helicopter rotor, bot with only one half. At competition, we got 1700 on high (with a broken resistor) but actually more like 360...he fixed the resistor before taking down scores

I just use a cut out piece of cereal box cardboard...O_o
What size basswood do you use to make the frame? I always thought that a covered frame would be too weak...

Not really, I use 1/8 square for the spars, or sometimes 1/8 by 1/16. My ribs are always 1/16th. It is actually sturdier than most cereal box things, and is lighter, which seems to get better results. I will post a picture later, if you want to see.

Yes, please do post a picture. I might have to give that design a try. Thanks.

I can't really say this without sounding arrogent(arrogant?), but for the last two years with only one exception, I've gone undeafeted at every competition I have gone to. It could just be that people in WA (no offense) are just bad at designing wind turbines, but last year me and my build team literally stumbled on to a design that has yet to be beaten, and its winning by a superwide margin. And all our attempts to rebuild and modify this particular blade have ended with it being worse than when it started. My question is, is anyone else experiencing this, or is our blade design totally unique? Also does anyone know of a superlight plastic I could replicate the design with, 'cause I'm thinking that plexiglass isn't exactly the best material we could be using.

devin159 wrote:I can't really say this without sounding arrogent(arrogant?), but for the last two years with only one exception, I've gone undeafeted at every competition I have gone to. It could just be that people in WA (no offense) are just bad at designing wind turbines, but last year me and my build team literally stumbled on to a design that has yet to be beaten, and its winning by a superwide margin. And all our attempts to rebuild and modify this particular blade have ended with it being worse than when it started. My question is, is anyone else experiencing this, or is our blade design totally unique? Also does anyone know of a superlight plastic I could replicate the design with, 'cause I'm thinking that plexiglass isn't exactly the best material we could be using.

Plexi is a very good material to use if you know how to use it. (and no I'm keeping that stuff a secret ) but what kind of numbers are you putting up against how much resistance?

Frogger4907 wrote:

devin159 wrote:I can't really say this without sounding arrogent(arrogant?), but for the last two years with only one exception, I've gone undeafeted at every competition I have gone to. It could just be that people in WA (no offense) are just bad at designing wind turbines, but last year me and my build team literally stumbled on to a design that has yet to be beaten, and its winning by a superwide margin. And all our attempts to rebuild and modify this particular blade have ended with it being worse than when it started. My question is, is anyone else experiencing this, or is our blade design totally unique? Also does anyone know of a superlight plastic I could replicate the design with, 'cause I'm thinking that plexiglass isn't exactly the best material we could be using.

Plexi is a very good material to use if you know how to use it. (and no I'm keeping that stuff a secret ) but what kind of numbers are you putting up against how much resistance?

I fully respect your secret keeping sir. with no resistance we've pulled a combined total of around 2.5V at compitition, we usually test at a higher load than compitition (to make sure it will turn), of about 10 ohms, and with optimal placement and if the stars are aligned correctly, we've seen it do around 600mv on high with an average of about 550-580mv.And it would be my desing I would be replicating, not yours. It also makes a lovely noise that soothes the soul.

PS. Feel free to mock me for my spellings, I is a physics person and I speak American, not english

How many mv are people getting?