Construction Manual
Wing Servo Installation
Choice of wing servos is critical on modern DLG’s. When an aileron or flap deflection is made you are moving 30% of the airfoil. It is very important that the servos you chose have excellent centering and resolution. If the servo you chose does not center, you leave yourself with a whole new airfoil each time you do a control input. If the geartrain is sloppy, it doesn’t matter how well you make the control linkage, that play will always be there. My personal choice for servos is the JR 241 analog or the JR 281 digital.. No, they are not the lightest or smallest but they have slop free gear trains and excellent centering and resolution. They can be installed flush in the wing but it takes a little work.
For demonstration purposes I was installing Dymond D60’s in a wing for a customer when I took these pictures so that is what you will see. For the record, I personally haven’t flown the D60’s but I am told they do OK.
The D60’s were slightly larger than the servo cut out in the wing. Place servo in position on the wing. I scribe a mark as closely as I can with the point of a #11 blade. The wing skin can be cut with a couple of passes of a number 11 blade or a single edge razor blade. The object is to fit the servo as snugly as possible and flush with the surface of the wing.
Trim the servo leads as short as you can and still make solder connections to solder the extension on. Feed your servo extension to the servo bay from the center hole. The leads should be kept as short as you can comfortably work with them to solder. Solder your connections and heat shrink. Plug in to the radio and check servo function and center. I like to have the servo arm tilted slightly back toward the flaperon to help increase flap travel. When satisfied that all is well, install the servo for the final time. Make the servo as snug as possible by shimming if necessary. (note the piece of foam cut and fit in at the top of the servo to help keep the servo from moving.)
When satisfied that the servo is as snug as I can make it and flush with the surface of the wing I like put just a little foam safe CA around the edge of the servo. I finish my install by making a servo cover out of reflective sigh vynal that I got at an art supply store. This seals in the servo and prevents any movement.
Make your aileron linkage from the supplied carbon rods. Make sure that there is no play whatsoever in the aileron linkage. Best set up is long control horn and short hook up on the servo horn.