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chia
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Re: Rotors

Post by chia » April 1st, 2011, 9:45 pm

I believe lower, since thinner rubber (unless you use more than one single loop) won't have enough power to turn a rotor with a high pitch fast enough to keep the helicopter in the air and rising. Someone else should confirm/correct that, though, to be sure.
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Re: Rotors

Post by illusionist » April 2nd, 2011, 6:58 am

I also agree. Assuming you use only one loop, a thicker rubber will most likely need a high pitch, while a thinner rubber will need a low pitch. The thinner motor has less torque, and therefore is unable to push the high pitched rotors fast enough to generate the necessary lift.
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Re: Rotors

Post by Kovu » April 2nd, 2011, 8:48 am

Okay thanks, I will work on building a high and low pitch and then experiment with different type of rubber to find the best combination.
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Re: Rotors

Post by illusionist » April 2nd, 2011, 2:18 pm

What size rubber are you trying to use? If it's 1/8, then I would start with a low pitch. If it's 3/16, I would start with a higher pitch.
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Re: Rotors

Post by Kovu » April 2nd, 2011, 4:05 pm

Yea for regionals we used 3/16 but I want to use 1/8 to get more winds in and a better time.
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Re: Rotors

Post by lllazar » April 4th, 2011, 5:02 pm

I've seen from testing that stiffer spars = higher flight time. All other factors kept constant of course. I think it has to do with the fact that if the spars aren't stiff then the rotors warp and change pitch during flight a lot more? Well anyway, i think a little weight gain would be worth it to make sure ur spars are nice and strong, and not so flimsy.
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Re: Rotors

Post by Draylon Fogg » April 4th, 2011, 8:41 pm

we were using mylar on ours and it was getting around 54 seconds, and we switched to tissue and placed 2nd at state with 2 mins 12 seconds, so like lllazar, stiffer rotors can make better times
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Re: Rotors

Post by Draylon Fogg » April 4th, 2011, 8:43 pm

i also saw an event supervisor had beams in the middle of the ribs for extra support
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Re: Rotors

Post by lllazar » April 5th, 2011, 7:24 am

Draylon Fog, you went from 54 seconds to 2 minutes+ by just switching to tissue paper? That's quite interesting...
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Re: Rotors

Post by chia » April 5th, 2011, 9:23 am

Draylon Fogg wrote:i also saw an event supervisor had beams in the middle of the ribs for extra support
How do you mean?
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