Jim,
I had already taken the LE off the rudder to fit a beveled edge for a more "conventional" hinge-line. This allowed me to plan and fit the rudder horn support. I also "keyed and notched" the horn plate a little. Then it was fitted with a chopped-fiber-expoxy cocktail and some gravity direction to the glue flow before it cured inside the rudder :-)
My geometry on the horn and servo arm did not have any length change propblems. You can check this very easily and accurately when the wire is piano-wire, by just connecting one side and giving a helping hand on the rudder during the push movement.
Troy suggested (advised) two ply U-control line wires due to their stiffness and non-stretchiness. He also said "go all nylon on the servo gear train".
What was also notable was how much less you could "flex" the rudder, by hand, when the system was turned on and at neutral. iIll reserve judgement on durability until I have had some stick time with this plane.
Regards,
Eric.
ORIGINAL: OhD
Hi Eric,
After I sent that message I guessed that you were referring to the rods vibrating. Of course if one ran them through teflon tubing like the elevator rods that would take care of the problem.
Don't you get in trouble if the servo arm lengths aren't the same length as the rudder control horns in a pull -pull system?
I also noted that you moved the control horns up near the mid-point on the rudder which is a good idea. Did you have to add material inside the rudder and how did you do it?
I assume Troy suggested control line cable that isn't supposed to stretch. Did he have any other good suggestions?
Always trying to learn, Jim O