Did some tests today....not sure what they prove, but here is the info.....I took a final gear output shaft from a Hitec MG servo and clamped it in my vise, put on various servo arma (Dubro HD and the black HD plastic arms supplied with the Hitec HD digital servos)...did a pull test on my digital scale and here's what I got...

the HD Dubro stripped the splines in the servo arm at 51 pounds....1" from the center of the arm

the HD hitec arms stripped between 45 and 52 lbs, also 1" from the center of the arm

the HD Hitec arms stripped at 64 pounds when the scale was attached .75" from the center of the arm, allowing more force on the scale due to the decreased leverage on the output shaft with the shorter moment arm (leverage)....

Finally, the aluminum output shaft of the servo gear sheared off (as the picture shows) after about 4-5 tests on it.....

Somebody that's a lot smarter that me feel free to chime in here regarding the validity of the tests....

The bottom line is, the splines are much stronger than I thought them to be.....how much force is the little nylon gear in the servos gonna take.....how much force will the hatch/mounting cover theat the servo is mounted to gonna take....how much will a clevis take, etc, etc, etc????

Couldnt test JR, as I dont have any......

If you're running a 180 oz servo, 180/16oz in a pound is 11.25 lbs of force (if the equation works that way....any engineers reading)?
the arm would never strip before the servo stalls out and the control surface "blows down" in the relative wind during flight.....