Twin engine hook-up question

[rhomodel]

Also posted this on Jim's but little response so searching further. As I'm in the finishing stages of the twin rigger build it is now time to think on some practical aspects. One of them is how to hook up the engines to ensure they throttle synchronised. I have seen many set-up using a sort of central bar, driven by 1 servo that would have 2 arms, one for each to connect to the carb.
My build has 2 radioboxes as I wanted to be sure to have buoyancy in case I break the booms and lose the sponsons. Will it work if I hook up 2 servo's with a Y harness to channel 2 and rig them up all the same so that engines would run synchronised? Servo's, rod connectors, carbs arms etc would all be the same of course.
Reason I ask is it is easier for me to have 2 seperate servo's than a central servo and rod.

 

[Mark Anderson]

Yes that will work with carefull linkage set up. Depending on what radio you are using, most have the ability to mix channels or assign functions. This allows you to plug into seperate ports on the reciever and have independant end points, centering etc. Or as mentioned on Jim's a seperate servo matcher could be used.

 

[RaceMechaniX]

As Mark suggested with careful linkage symmetry it can be done easily. Some servo's like the latest HiTec models can be programmed to offset the neutral position in case the servo horns are slightly off from each other. You can also set the EPA's from the programming box to adjust the high and low limits. There are also black box servo synchronizers like the Futaba MSA-10.

Futaba MSA-10

 

[Mike Hughes]

My gas rigger is set up with 2 servos. That way I can set all end points and travel separately. I have both servos on separate channel and program a mix so one is a slave to the other. Doing them with Y is a little more difficult if they are not exactly the same linkage but still will work fine after adjustment.
Mike

 

[rhomodel]

Great, thank you. Though I can not mix channels, other than gas and steering, it's re-assuring it will work. As soon as that part is done you'll see the pictures in therigger hydro sub-forum.

 

[John Beardslee]

As Mark suggested with careful linkage symmetry it can be done easily. Some servo's like the latest HiTec models can be programmed to offset the neutral position in case the servo horns are slightly off from each other. You can also set the EPA's from the programming box to adjust the high and low limits. There are also black box servo synchronizers like the Futaba MSA-10.

Futaba MSA-10

Tyler did Hitec change their system? Years ago you could program their servos using their programmer but only if you were using their receiver and transmitter.
Thanks John

 

[John Beardslee]

Great, thank you. Though I can not mix channels, other than gas and steering, it's re-assuring it will work. As soon as that part is done you'll see the pictures in therigger hydro sub-forum.

If you go to Chief Aircraft’s RC department, they sell a servo synchronizer for 2 servos for about $26. Well worth it in my opinion. I us JR RC Matchbox but only because I have many from my giant scale airplanes where I would sync as many as 4 servos on each wing aileron.
John

 

[Tom Foley]

I have successfully used one servo and a dual pushrod in a Y setup . It works good but some other setups are a little better . Bellcranks below .

 

[RaceMechaniX]

Tyler did Hitec change their system? Years ago you could program their servos using their programmer but only if you were using their receiver and transmitter.
Thanks John

Don't think so John, I have quite a few of the Hitec servo's that operate on a Futaba radio system and I could independently adjust the servo via the programmer.

 

[John Beardslee]

Don't think so John, I have quite a few of the Hitec servo's that operate on a Futaba radio system and I could independently adjust the servo via the programmer.

Okay, thanks. Good to know.

 

[Wasted wages]

I've done it both ways... linkage and single servo and dual servos with Y-harness.
Never saw an advantage or disadvantage..one over the other.. but I do like the dual servos better.. Less junk in the radio box and less chance of something moving and jamming the linkage..

 

[rhomodel]

Thank you all for input. Let me do dual servo set-up and see how that works.,.