stevehord

My Feedback: (1)

Does anyone have advice for adding ailerons to a 1/2A kit? I'm building a Herr 1/2A J3 Cub and see the plans show an outline for ailerons starting in the wing tip, extending in about 10 3/4"? However, I am not sure how to proceed. Any help will be appreciated.

Thanks,
Steve Hord

Mike Taylor

My Feedback: (1)

You really only have 3 options: Run a sheath-and-cable type push rod through the ribs and make as smooth a 90 degree arc at the aileron end, run pull-pull cables through the ribs in a teflon sheath (CA capillary tubing works for the sheath, and kevlar thread works for the cables), or run torque tubes through the narrow rear parts of the ribs.

I wonder if pull-pull is suitable for 1/2A since the oil could gum up the cables. The torque tube would take up most or all of the rib depth on that model. That sort of leaves flexible push rods...

Here are some pictures of a smaller 18" electric model's ailerons using the flexible push rods in a teflon sheath inside the wings. The servo arm shuttles a follower that is attached to the push rod (.008" music wire in this case). The sheath is attached to the spar, and it sweeps through the 90 degree arc. The sheath is just visible in the first photo. As the servo travles, it pull one side and pushes the other.

The second picture shows the cable exiting the tissue, and the sheath can be seen making the sweep. The third photos shows the final hook up with a 'Z' bend.

Check your LHS for fine Sullivan golden rods; they should be easy to install and come in sizes small enough for 1/2A...

combatpigg

My Feedback: (3)

HI STEVEHORD! One option is to install a seperate HS55 in each wing panel, and wire the servos in parallel back to channel one. Another way to go is to make the ailerons full span, and have a single HS81 or HS55 drive both flaps from the center of the wing. A pair of push rods that run out to the control horns at an angle work OK, and if you did it on the underside of the wing, it wouldn't look too funky. There are other more complex ways that look better, like torsion bars, and flex tubing inside the wing[NYRODS], a lot depends on how much work you want to put into it.

stevehord

My Feedback: (1)

Thanks for the information everyone. I definitely need to determine how much work I want to put into ailerons but with several ideas I now have a good start.

Thanks again,
Steve Hord

Cautrell05

heres a pic of how I did the ailerons on my 24" guillows cessna. the servo will be mounted in the center of the wing to the front.