mr.warriorz

Hi, im setting up my new f-18 and the elevator has a servo on each side. They are connected to a Y connector. But each side of the elevator move in the opposite direction.... Like ailerons. How do i make them move in the same direction? Im using a DX6i.
Thanks.

JetPlaneFlyer

Buy a Y lead with a servo reverser module built in: http://www.servoshop.co.uk/index.php...1044&area=ACCS

Steve

kenchiroalpha

Hi Kyle
Those would be called elevons
To program flaps and spoilers check out the videos here
http://www.youtube.com/view_play_lis...C2958453C5541E
Its also described in the txs manual
http://www.spektrumrc.com/ProdInfo/F...anual_DX6i.pdf
Hope this helps
Take care
Yours Hank

JetPlaneFlyer

Hank,
they are only elevons if you want them to work as elevators and ailerons. If the model already has ailerons on the wings then you probably just want the elevators to work as elevators.. So if you cant position the two servos so that you can come off opposite sides of the servo arm, then you need to reverse one of the servos.. hence the servo reversing Y lead.

Old Fart

What reciever are you using?

mr.warriorz

ar6100e

Old Fart

Run each half to a separate channel in the RX and mix them in the transmitter if you can.

dumo01

But the critical piece of info here still remains:
Are they supposed to be elevators or elevons?

squidger

If he does as Old Fart says he can program them to be elevons which will assist the roll.

JetPlaneFlyer

But then what does he do with the ailerons on the wings? You would and up with very complex mixing where the elevators worked as elevons and the ailerons worked as flaperons. Flaps and elevator would be mixed, presumably flaps would go down as elevators went up.

While this may work it would be safe to just use the elevators as elevators and the ailerons as ailerons?.. The KISS principal.

squidger

The ailerons would remain as ailerons and the elevators would use elevon mixing so both go up or down with elevator input but work in opposite directions when ailerons are used.

Nitro Blast

This elevon setup is remarkably good... roll rate that is clinically insane!

[media]http://vimeo.com/5578144[/media]

Old Fart

Not sure how much value in suggesting a fairly complex mix on a radio like the 6i. With a 9303 or a 9C, lots of fun possibilities like "aileron/elevon", "elevator/flap", etc

Larry3215

That works fine for the elevons by themselves - but, what Jetplaneflyer is saying is that the ailerons would ALSO move in the same way.

In other words, if he does that he will also have flaps/reflex automatically mixed to elevator. Not necessarily a good thing.

becides which, unless he has a higher end radio, he may not haved the option to program around that problem. Even so - it will be some complex mixing at best.

kyleservicetech

If you're using Spektrum receivers, be aware that one of my club members nearly lost a giant scale model with a 50 cc gasoline engine due to one of those "reversing harness cables".

The elevator servo connected to that reversing harness went to full up during the flight. (I saw it happen) It was still full up on landing.

He contacted Spektrum, who responded, "Don't use those reversing cables withour equipment". They have had problems. He mixed in the second servo through the transmitter and Aux #2 servo, and had no further problems.

Note that in the Spektrum DX7 transmitters, you need to use one of the "last two" mixes for this purpose, otherwise the servo trim on your transmitter will only move one elevator.

If you've got the mixing available in your transmitter, just mix in the second elevator servo to an unused channel (Aux 2?) on your receiver. My Spektrum DX7 transmitter and AR7000 receivers make this an easy solution.

squidger

I see what you are saying but I didn't mention flaperons. What I meant was the ailerons working just as ailerons and the elevators as elevons like in the film clip Nitroblast has posted. I realise you need a good radio to do this but it is entirely possible.

JetPlaneFlyer

It's not possible with the DX6i (which is the transmitter the original poster has)...

If two elevator servos can be put on the 'last two' mixes, as suggested by Kyle, working as plain elevators but with direction opposite handed then that would be the way to do it... I'm not sure if that can be done with the DX6i?

I dont see any reason in principal why a servo reverser should be more likely to fail with one brand of RC gear over another? But inevitably a reverser is another component that has the possibility to fail and the quality of some of them may be less that ideal, so if you can do it without the reverser so much the better.

Steve

Flyer495th

I would take one of the servo's bottoms off and change the 2 wires on the motor & also the 2 outer wires on the pot. Put it back together and use a regular Y. I have done it many times quick and easy fix.

Larry3215

Check the user guides for some of the Spektrum rx's. They say not to use AMPLIFIED Y HARNESSES. It doesnt say anything about servo reversers.

However, there have been reports of reversers also causing erratic servo operation with Spektrum gear.

I suspect some of those reports are due to using cheap reversers from HK etc and may have nothing to do with Spektrum.

kyleservicetech

Not certain about this, but suspect that the servo reverser used by my club member was borderline in providing the proper signal voltage to the servos. Might have been that the club member was using a 5 cell Nicad pack which provided more voltage than the servo reverser was rated for.

Don't know. At any rate, trying to control and land a giant scale model that had one elevator section full up was a very scary thing to watch.

kyleservicetech

Don't know about the newer servos. Many of them have the motor directly soldered to the servo's circuit board, making it very difficult to rewire the connections.

Simon

Well, considering both servos are simply connected via a Y-Harness, one would expect both servo shafts to rotate in the same direction. If you can't plug one of them into another channel (to enable mixing and channel reversing etc) becasue they're all used, you may wish to consider the following work-around.

If the servos are mounted in the same orientation, this will present a difficulty - can you not orient them such that the same direction of rotation translates into opposite movement?

I.e have the wire exiting one servo towards the nose of the plane and the wire exiting the second servo towards the tail. They do say that a picture is worth a thousand words..