Building techniques

jander14indoor
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Re: Building techniques

Post by jander14indoor » January 21st, 2011, 4:20 am

Spend some time reading back through the threads on this forum, its been covered. Then try more specific questions.

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Re: Building techniques

Post by aubrey048 » January 22nd, 2011, 9:46 am

Okay. What dimensions of balsa wood do you guys use for the rotors and wings? I know blue cobra kind of answered this, but I need a really specific answer if at all possible.
My partners and I are trying to figure out what to buy . . .
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Re: Building techniques

Post by smartkid222 » January 22nd, 2011, 1:58 pm

If you are making a rotor that wll be covered with mylar or plastic then 1/16 x 1/16 balsa wood is most common.
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Re: Building techniques

Post by illusionist » January 23rd, 2011, 7:09 am

aubrey048 wrote:Okay. What dimensions of balsa wood do you guys use for the rotors and wings? I know blue cobra kind of answered this, but I need a really specific answer if at all possible.
My partners and I are trying to figure out what to buy . . .
BTW, for these helicopters, unless you are using a vertical surface to counteract the torque of the rubber, rotors are the "wings".
1/16 x 1/16 are teh best for the rotors. The motor stick sizes have been discussed in other threads on this forum
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Re: Building techniques

Post by aubrey048 » January 24th, 2011, 7:12 am

Thanks guys!!!
:D
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Re: Building techniques

Post by illusionist » February 26th, 2011, 4:38 pm

I am going to try building my rotors from now on with a jig. I'm still experimenting with finding the right pitch. So, I plan on building a jig like this one: http://www.turnertoys.com/G1/parlorcopter.htm (scroll down a bit). Does anyone have dimensions that have provided a successful pitch?
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Re: Building techniques

Post by chia » February 26th, 2011, 5:21 pm

What sort of pitch have you tried? I think lower pitch might get you up to the ceiling, but depending on your rubber might use up your winds too fast, and higher pitch would, with too thin a rubber, not generate enough lift...? I honestly don't know if what I just said was utter nonsense, but that's my (possibly messed-up) understanding of it. Could anyone else please clarify?
Similar to illusionist's question, have wider or thinner rotors, "chord"-wise, worked best?
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Re: Building techniques

Post by illusionist » February 26th, 2011, 5:26 pm

I agree, too high of a pitch provides lots of thrust, lots of resistance, but requires a large amount of torque. A low pitch provides less resistance, less thrust, fast rpm, but uses up the turns very quickly (especially with thicker motors). I don't know what is ideal.

http://www.turnertoys.com/G1/parlorcopter-3.htm (scroll down)
^ There are dimensions for a jig. I've built a rotor with those, have yet to try it out. Btw, I'm using 3/16 rubber.

I wish there was a formula for this :x
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Re: Building techniques

Post by illusionist » February 27th, 2011, 6:31 pm

Should the lower rotor be set at a higher pitch than the upper rotor? I would think so, since it needs to move the air faster, that is already in motion due to the upper rotor.
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Re: Building techniques

Post by lllazar » February 27th, 2011, 9:42 pm

Both my rotors are same pitch, i think i'll try that though.
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