I am building a Great Planes Cherokee. I have installed the servos for the flaps, but the travel on my servo is more than I have on the flap,causing it to bind hard when I turn the Knob on the Tx all the way. I know the simple answer is dont turn the knob so far, but in an actual flight I will have no way of knowing when the flaps are fully deployed, or when I have gone too far. I have a futaba skysport 6A Tx. It has an adjustment screw for the flap channel, but when I turn it does not change the travel of the servo. Here is a link to the manual. I have tried to follow the instructions, but I have not had any luck.

[link=http://manuals.hobbico.com/fut/6va-manual.pdf]Skysport Manual[/link]

2 Questions

1. Can I adjust the travel of the servo with My Tx?

2. Would sortening the arm on the servo make a significant difference in the travel of the flap?

Beagle,

There are two things you can do:
Move the connecting rod in on the servo.
Move the connecting rod out on the control surface.

This should be done even with a computer radio.
Get the throws as close as possible mechanically and then fine tune electronically.

Good Luck,
KW_Counter

short arm on servo and long arm on control surface will give you the least amount of control deflection. I don't have that radio so I'm not sure if it has ATV for that channel, my futaba 8U does

Not having any knowledge of the TX you have cannot give you a sensible answer on what it can do. I know that most TX. do have adjustment for servo throw. Yes if you locate the arm shorter on servo arm it will give you less throw.You could also locate it further out on flap horn reducing throw even more. However these adjustments will increase the required power from servo to move flaps. By the way if you don't have a fair amount of flying experience you are increasing the difficulty of flying successfully by using flaps.

According to the manual it does not have ATV for the flaps.

I used to have this radio. I seem to remember a plastic piece that you could slide over the flap knob as a stop. Depending on where you put the piece you could limit the travel of the knob. It's been a while so I could be wrong about that. Even so, you could probably rig up something similar.

I just checked mine (I used it for a buddy box) but I didn't see anything on the flap knob, but I have had it a long time. I really think you are right, that it did have a knob limiter.

Thanks for the advice. Currently The control rod is connected at the ends of the servo arm as well as the control horn. I will move it on the servo arm and see what that does. To do this I will need to lengthen the rod. Currently I have nylon connector fully threaded on the end of the rod. How far can I back this off to gain the needed length?

This radio is new in the box, I will look to see if I can find some type of a clip that can limit the travel on the knob.

Thanks again for the advice.