Hi folks,

Still working on my 4-60 and I have a question regarding the aileron servos. Those who have built this kit know that the servos are affixed to a hatch cover and installed under the wing. The servo arms then extends out from a slot opening in the hatch cover.

So here's my question: I am using JR DS821 servos, and when I install the servo on the hatch cover, the standard arms that come with the servo extend out of the slot sufficiently when the servo is in the center position, but when I move the servo to either extreme, the servo arms move below the surface of the hatch cover. I hope this makes sense, if not, let me know and I'll try to post a picture or two.

Assuming you understand what I am trying to describe, do I need to buy longer servo arms so that they always stay above the hatch cover through the range of motion? If so, how do I buy horns that match my servo? I looked on line but cannot specifically identify those arms that match these servos.

You should be fine with the servo the way it is, and the control horn. Since the servo is mounted in the underside of the wing, your actual horn tavel will be 20 degrees forward, from 0... and 30 degrees aft, from 0. This is really all the motion the ailerons require for flight, and should be settable in your Tx. During normal operation, the horn will never need to go to either "extreme". Be sure to check your throws for final adjustments. 30 degrees up, 20 degrees down aileron.

You will need to get a longer arm and keep the push rod on the outside of the mounting plate for the entire range of motion. Here is some that I found. Good Luck, Dave


http://www3.towerhobbies.com/cgi-bin...?&I=LXD669&P=7

Those are what I have on mine and work fine.

This is also what I used on mine. You will one day want the extra travel!

These are a good idea to have in you box. As I recall I used them on the 4* 60 but really can't remember.

You should have full range, I used hitek 635's and they come with an assortment of arms. I think the one i used is about an 1" long.

Appreciate the responses everyone. I'll pick these up.

You might want to pick up a couple longer horns for the aileron in the process. If you set it up so the hinge line to the link attachment is equal to the center of the servo out put shaft to the link attachment, you are it good shape. I did that with both of my 4*60's and now I'm using ball links on the servo arm and Robart ball link horns . The ball link requires a little longer servo arm. for clearance, and if you get a set of Dubro heavy Duty arms to fit your servos, you will be in good shape.

Don