Aeroworks 85cc Yak 54 Rudder Linkage

[Smacka]

Hi All:
I have opted to use a single 400 oz rudder servo, instead of two 180 oz servos. That said, the manual recommends a straight 3 1/2-inch full rudder servo arm. I was on SWB's website and they only advertize a 3-inch straight full servo arm. The only other arm close is their 3 1/2-inch full offset servo arm, which is designed to use with rudder cables that cross in the fuselage.

Can this offset arm be used for my application, even though I do not plan to cross the cables?

Thank you!

[bodywerks]

Chances are pretty good that you will come out a little noseheavy. I would just mount the servo in the tail. Aeroworks should have put an optional rudder servo slot back there - they do on all their other planes
If you are bent on going with the extra complication of a pull-pull setup, get the SWB 2-1/4" full arm(4.5 total length) and put the ball link on the 3rd hole in. I also recommend putting the ball link on the bottom of the servo arm so that the load is placed more in-line with the shaft bearing. MOunting it on to induces a tortional load that can cause premature wear on the servo.
The Aeroworks control horns also have three different holes that you can mount the ball link to, so you have options. In fact, I am only using 1.5" single arms on my 42% Aeroworks, so I don't see how you would need more than a 3" arm.
Measure the distance from the hingeline to the outer hole on the control horn. It shouldn't be more than 1.5", if that.

[Sevans16]

Check out my thread on here in the GS Git R Done section.

I used a Greeves pipe, pull-pull setup and it is balancing at 4" back, 1/2" past the 3.5" mark called for. I also set mine up with the 1 1/4" full arm. The 1.5"(3") arm would be plenty I think??

[Sevans16]

AeroWorks 85cc Yak Build w/pics

[Smacka]

	Quote: Originally Posted by bodywerks
	Chances are pretty good that you will come out a little noseheavy. I would just mount the servo in the tail. Aeroworks should have put an optional rudder servo slot back there - they do on all their other planes If you are bent on going with the extra complication of a pull-pull setup, get the SWB 2-1/4" full arm(4.5 total length) and put the ball link on the 3rd hole in. I also recommend putting the ball link on the bottom of the servo arm so that the load is placed more in-line with the shaft bearing. MOunting it on to induces a tortional load that can cause premature wear on the servo. The Aeroworks control horns also have three different holes that you can mount the ball link to, so you have options. In fact, I am only using 1.5" single arms on my 42% Aeroworks, so I don't see how you would need more than a 3" arm. Measure the distance from the hingeline to the outer hole on the control horn. It shouldn't be more than 1.5", if that.

Actually, this makes a lot of sense, and I appreciate you taking the time to write your thoughts. I believe I will be able to use a 3" full straight arm for the rudder.

I will build the aircraft to the point of having to decide where to mount the rudder servo. I will check the "CG" and move the rudder servo around from the pull-pull area, back to the tail and see where it balances right at 3.5 inches from the leading edge of the main wing. I do not have a problem setting up a pull-pull if the balance is correct in the pull-pull servo area. I do agree, the rudder servo on the tail is easier all around, and that is how I built my H9 27% Cap 232G. The "CG" was perfect with the rudder servo on the tail.

Thanks again!