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Old 10-25-2008 | 01:01 PM
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opjose
 
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From: Poolesville, MD
Default RE: Nitromodels Katana 50cc build thread


ORIGINAL: outssider

i believe that 160 oz for that size rudder is border line ! but since you got it, try it ! make sure to use 6v. Hardest stress on that servo will be with a knife edge loop or a full power flat spin. If it holds on those, it should be ok!

I agree with you, but I've found that even a single 150 oz servo ( the manufacturers of course always overstate their specs, so in reality it will be akin to 130oz/in! ).... holds fine (PROVIDED... ).

I've tried this in the 50CC Edge 540T. I had the rudder set up for high mechanical advantage...

However I also supply PLENTY of power to the servos at 6v too, which is a mistake often made.

At high draw a 160oz/in ANALOG servo can draw over 2.2 - 2.6 AMPS!!!! And that's ONE servo!

Throw in a measly 2400mAh battery pack, and there is NO WAY the servo, let alone several will hold under load.

So equally important is to provide sufficient reserve.

Of course a higher torque servo or ganging two lower torque servos is advisable, especially on the rudder.