ORIGINAL: overbored77
Rock I firmly agree with you on the servo size for the plane he is using. But I was thinking if he has 4 DS 821
sport digitals with 60+ at 4.8 volts, why not use them on all control surfaces and go with a lightweight mini on the
throttle. This will give the added advantage of good centering and resolution, combined with good torque.
and the Hitec HS81 will cost less than $20.
Decent plan but..........
I always figure that there is going to be a next airplane to come. And those DS821s are excellent high torque digitals. Which means they're really good for an elevator which is almost always a heavily used servo and heavily loaded one as well. And since aileron loads are easily handled by one servo, then any two servo setup really doesn't benefit from having even a regular strength, so why not.............. save two DS821s for the next airplane and save an ounce of weight overall and have excellent centering and resolution and more than enough torque with 225s. But I was looking at perfecting this and the next airplane. Not keeping the cost as low as possible. Which is never a bad idea.
Having that much torque out in the wings on ailerons is way overkill. But if you already got 'em why not use 'em. Other than once they're there they probably will stay there until the airplane is crashed. And the next airplane might come about before that happens.
Using the HS81 is an excellent idea before even considering the low price of that servo. Saving weight is always a positive.