[quote]ORIGINAL: JoeAirPort

Say you used a 7955 Hitec servo at 333 ounce-inches. If your servo arm were 3, you'd have 333/3 = 111 ounces of cable tension at max rated servo torque. 111/16= 6.9 pounds. So I'd say 20 pound would work. I



Not to nit-pick you math.....but, if the arm is 3 (inches) from pull cable to pull cable, it would be 1.5 inches from the center of the servo shaft to either cable. Since Torque=Force x Radius, you would divide 333 by the radius of 1.5 inch, giving you 222 ounces, or 13.9 pounds on the cable. Either way, it would probably be okay. Especially since, in my opinion, a 50 cc planes rudder servo would never see 333 ounce inches of torque. I think I use 26 pound cable.

Mike