9c 4 servo elevon trim problem.
 

Hi guys.

Im setting up the elevons on my hotspot with 4 servos.
Im using the method stated here: http://www.futaba-rc.com/faq/faq-9c-q510.html , but I cant seem to get all 4 servos to trim when trying to trim the aileron part. Only the 2 outboard servos move when i trim aileron. If i trim elevetor, then all 4 servos move.

Anyone run into this ?
I guess it would be ok to only trim the outboard elevons ??


http://bornholm.adsl.dk/modelfly/fil.../Dsc00592s.jpg


SJ.

9c 4 servo elevon trim problem.
 

Hi SJ,
I ran into the same problem in settin up my 'Roo.
I solved it by being lazy :D and just using a "y" harness on each wing. Right wing is Ch1 left wing is Ch2, elevon fxn on.
I've got less than 1/64" difference between surfaces at full throw.
The airplane doesn't care, and I don't anymore! :)
Have fun
Greg

9c 4 servo elevon trim problem.
 

Thanks Greg, Guess ill just have to live with it as it is....

not too big a deal only being able to trim "aileron" on the 2 outboard surfaces i guess.

SJ.

9c 4 servo elevon trim problem.
 

Before you give up - you may want to try asking this question on the Futaba support forum - it's a sub-forum of the radio forum, and you can get a lot of good info there.

Gordon

9c 4 servo elevon trim problem.
 

Ill try that, thanks Gordon.


SJ.

9c 4 servo elevon trim problem.
 

SJ.....ECH!-WRONG!
By "Y" harnessing the two servos in each wing, they work together in both aileron and elevator mode.
When you trim aileron, they have no choice but to work together, the same with elevator.
I would be leary of trying to trim things with only 1/2 of an elevon responding....
I agree with Gordon that there has to be away to work them individually, but the onlty way I know how is described by Don Edberg in his 8U book, and that uses up 4 channels.
Add to that the simplicity that I (and a bunch of others that even I know of) have found with the "Y" harness adn...."Simple is good".
If you find a better way, PLEASE! let us all know!
Greg

9c 4 servo elevon trim problem.
 

Sure. But the guys that are going to check, and aprove my model do not allow the use of Y-cables on the primary flight controls......

Why would it be bad only to trim the outboard surfaces on the "aileron" ?

9c 4 servo elevon trim problem.
 

Because the roo needs reflex in the control surfaces! changing trim on just half the elevon on each wing will give you nasty flight habits. Why would anyone have a problem with using a Y cable on a primary flight control? What's the problem?? BTW, this can be done with the 9C, four servos on seperate channels for elevons is possible although I dont completely remember how we got it to function. I think the trick is to use both the Flaperon and Ailevator pre-programmed mixing functions.

CH1 = Right aileron (outboard)
CH2 = Right elevator (inboard)
CH5 = Left elevator (inboard)
CH6 = Left aileron (outboard)

Turn on Flaperon (FPN) mixing. This will slave the CH6 aileron to the aileron stick. Change the signs as needed to get the proper travel directions (opposite motion with aileron stick movement).
Turn on Ailevator (ALV) mixing. This will slave the CH5 (left elevator) servo to the elevator stick. If you want the inboard controls to also act as ailerons, use the A-3 and A-4 settings to get proper aileron travel directions. If you just want elevator, set A-3 and A-4 to zero (0%).
4. If you want to get the entire trailing edge to respond to elevator, turn on elevator -> flap mixing (E-F), and choose the percentage needed to get the throws desired. Choose sign to get proper direction of outboard control motion.
Make sense??
Todd

9c 4 servo elevon trim problem.
 

Thanks Tod.... but the futaba manual has a flaw in it....somehow.
No one can get it to work.

I actualy found this great info in another thread using the search engine :-) : http://www.rcuniverse.com/showthread...o+elevon+setup

I set it up like the great Dr. Phil Cole says to, by using the elevon mix, and just using 4 P-mix`s to slave the elevator and aileron functions.... works great now..