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Old Mar 11, 2012, 04:42 PM
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what weight to thrust ratio should I be aiming for?

Im building a quad from from parts that my brother gave me and dont know what size batterys to get. what weight to thrust ratio should I be aiming for on my qaud? im interested in the longest flight times of smooth flying, no flips acrobatics etc. im running nx4008's on 4s with either 10x4.5/4.7 props or 11x4.7 props.
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Old Mar 11, 2012, 04:56 PM
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I think thrust is 2x total weight. But, check http://www.flybrushless.com for the thrust measurements vs. RPM. If your motor is listed there you can get some insight into the power requirements as well. Basically you want to hover at about 1/2 throttle.

If your frame size permits, you could even try 12x3.8 slow-flyers. In some static testing I did, they gave a bit more thrust than the 11's.

Regards,
John
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Old Mar 11, 2012, 05:00 PM
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Quote:
Originally Posted by jpsabo View Post
I think thrust is 2x total weight. But, check http://www.flybrushless.com for the thrust measurements vs. RPM. If your motor is listed there you can get some insight into the power requirements as well. Basically you want to hover at about 1/2 throttle.

If your frame size permits, you could even try 12x3.8 slow-flyers. In some static testing I did, they gave a bit more thrust than the 11's.

Regards,
John
he wants to run 4s though? 12/38 might be a bit much for 4s
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Old Mar 11, 2012, 05:14 PM
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You want to hover at 50% throttle. 50% throttle= 1/3 total thrust. So for the props you mention your AUW should be around 1200-1400 grams.
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Old Mar 11, 2012, 05:50 PM
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i got a naza board if that makes a differnce
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Old Mar 11, 2012, 06:13 PM
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It does not make any difference.
Thrust at mid throttle must equal AUW.
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