Servo torque

Used the 1" x 20" aileron example at 70 mph in the calculator the result was 16.3 ounces. My guess factor was 20 ounces

Also tried 1.25" x 24" at 70 mph the calculator result was 31.3, my guess factor was a 30 ounces.

So 1 ounce of torque per square inch of control surface is in the ball park for any plane not exceeding 70 mph.

I think one part of the calculator has a bad value. The default servo deflection from center is set at 45 degrees. When I plug in 1.25" x

24" at 70 mph. 45 degree control surface deflection and 45 degree servo deflection the result is 18.09 ounces.

But unless I am mistaken a JR servo only travels 60 degrees stop to stop. So thats 30 degrees deflection from center. Change the servo deflection to 30 degrees and the torque required jumps to 31.3 ounces.

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I suggest you newbies just might stick around for a little while and see the frequent posts the good Dr makes that are very very helpful. He has posted to this group for many years and his posts have consistantly been brief and to the point. His advice is very good. Just because u are a newbie and do not like his advice does not give you any right to come in here and start slinging mud. I would suggest that several of you owe the Dr an appology. His answer was not in the slightest a smart remark. It was the best answer that has been given to the original post. Following all the other answers risks a inadequate sized servo followed by a crash. I an sure that the Dr would agree that a 40 once servo in general would be adequate for this sized plane. But those of us that actually have flown for years have seen more then enough strange designs and improper construction so we are more then a little fearful of committing from time to time. ie, I saw a new plane show up at the field recently that had 3/8 inch gaps in all control surfaces. And the way the controls were hinged this gap would increase with deflection in some cases. Further the plane is about six steps above the persons non-flying ability. As far as I know no one told this person to take the plane home, cut off the controls and put it together correctly. If they had there would have been a newbie explosion.

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