I then did the normal mounting of the servo and arm. The instructions are spartan at best although anyone who has ever built a plane or assembled an ARF shouldn't have any issues. I am using MPI 1 1/4" arms for this plane.


As I stated earlier there are no instructions on placement of the control horns so I winged it !! [8D] I Ran a straight edge down the side of the servo (which is 90 degrees to the hinge line) and transferred a mark on the aileron. I then moved the servo arm to the end of its travel and measured the distance from the hole on the arm to the side of the servo, once I had this distance (18mm approx) I transferred it to the aileron. The only remaining thing was finding out how far into the aileron to drill the hole and this was easily found by putting the control horn over the hinge line so that the hole in the arm is directly over the hinge line and marking the point where the control arm should go through the aileron. I made my mark and drilled though the hardwood bock. Once through I always put some thin CA in the hole to harden it more and then mounted the control rod.
What this does is give you great mechanical advantage when your surface is fully deflected. The pushrod is 90 degrees to the flying surface.

I also like to do a little sumtin-sumtin extra with the linkages. I lower the push rod linkage so that it is exactly the same height as the servo arm when the surface is fully deflected. The way the control rod is exactly parallel with the servo arm. Once again providing every little bit of mechanical advantage from the servo.

The finished product: Now do the other wing