LOL Kelly, we had some comunications problem... i'm around roos since 98! the pics I meant where about the wings and the elevon rods... nice paint scheme from yours, btw.

He is the picture of the linkage of my wing and yes I only have on s9151 on each wing. And the ATV 100%-+. I'm looking at 8611a or the futaba s9152/s9153, I would go with the futaba, but the shaft is not standard size and I will be hard to find aluminum or heavy duty horn.

ok, use 2 servos per wing, or go to the new jr 8611A 280 oz at 6.0 v

that will fix your problems


mark

I really don't think that your linkage setup is at optimum...You have a short "horn" at the elevon and a long servo arm with the linkage at the outer most hole at the servo to get enough throw. Does your Futaba tx allow you to set the ATV above 100%??? If so, you should set the ATV as high as it will allow and adjust the linkage to get the proper throw. When properly set up you should have the linkage at the elevon as far away from the control surface as possible and the linkage at the servo as close to the servo output shaft as possible. This will get you the maximum mechanical advantage.

Kevin

Bingo! that's the problem. your arm setup looks much more like a 3D airplane! you are getting about half the force available of the servo at the elevon with that long servo arm. Before buying
a stronger servo, try to use a servo arm with half of this lenght and tell us what did you found....

K.Greene, the Futaba radios can achive 140% of servo travel. I am actually using 110% in my roo
with the short arm... (plenty of throw on my elevon on my plane)

Best regards, Enrique

Yup... Definite mechanical disadvantage with this particular linkage setup. Just what I expected to see. This geometry is providing far less torque than the servo is capable of delivering. Yes, a higher torque servo would eliminate your "Softness" at high speed but, setting your linkage up correctly would most likely cure the problem without having to spend $200+ on servos.
Todd