dual elevator servo
 

Do you use dual channels or 1 channel and a y-adapter when setting up a dual servo elevator system?

RE: dual elevator servo
 

depends on what radio you are using... if you are using a radio capable of dual elevator setup do it that way.. if not use a reversing Y-harness since both servos will have to be facing the same to get both half geometry right

RE: dual elevator servo
 

I'm using a 9303 and it has mating capabilities. However, I have read somewhere that it's better to use a Y-adapter for it.

RE: dual elevator servo
 

i dont see how it could be better.... You are distributing the channel load through 2 channels and you will be able to end point and sub trim each servo seperately..... a 9303 will do the setup no problem

RE: dual elevator servo
 

I did do it that way but one servo travelled farther than the other so I adjusted the end points of one. Now, when you give it full elevator the two halves line up. But if you give it, say 50%, the two halves don't line up.

RE: dual elevator servo
 

Hi!
I just got back in to the hobby after being gone for 15 years.
I assembled a U-Can-Do 60 and bought a new Futaba 9C.
Before I bought the radio I started to use one of my old ones that wouldn't support seperate elevator servos on seperate channels. I was going to use a reversing y harness.
When I gave up on the old radio and bought the 9C I went the seperate channel route. I can now have "ailevators" when I'm ready to try that![X(]
One thing I did notice on the UCD.
There is a slight difference in the geometry of the two elevator linkages.
This caused a slight difference in total travel on each side...one elevator had a slight bit more up and down.
I thought I would simply eleminate it with the end point adjustment.
When I did I got a difference in response time.
One elevator would lag behind the other.
I decided to reset the end points and fix the difference in elevator deflection by mechanical means and used one slightly longer servo arm.
I am using S3151 servos on elevator. Don't know if the fact that they are digital caused the lag in response time when I was messing with the end points.
Hope this helps.
If anyone can tell me if I did something wrong I would appreciate it.
Thanks!
JLK

RE: dual elevator servo
 

there is a sub trim out of adjustment or the servos are not facing the same direction with the horns in the same direction.... also check in your dual rate setup area and make sure the numbers are the same between the 2 channels.(i had this problem once .. both channels should be the same in end point and dual rate throw

RE: dual elevator servo
 

I will look into the mechanical aspect of it. Thanks!

RE: dual elevator servo
 

Drumbum, I don't think there is a seperate dual rate for the 2nd channel. It automatically does it for both channels. But there is seperate ATV's and subtrim.

RE: dual elevator servo
 

everything has to be the same on both channels... if it still is not deflecting the same i would say your mechanical setup is what i would look at... do some digging and mmake positive everything is the same and check the mechanical... I have overlooked 1 thing in programming both channels and it drove me nuts untill i figured out what it was... I have a 6102 and a friend has the 9303 and both are setup on seperate channels .. the oly time we have had a problem is when there was something in the programming or mechanical that made a difference in deflection...
extra addict is the one with the 9303

if anyone else has any suggestions please advise also..

RE: dual elevator servo
 

I would look at your linkage I use my 9303 for all my planes and I have never had a problem. I have heard of people having this problem with some hitech servos if they are not the same version. So if you are running hitech digitals they will have a version number wrote on them somewhere make sure they match. I hope this helps!!!

RE: dual elevator servo
 

In case you haven't figured it out yet - switch the channels the servos are plugged into. If the problem stays with the servos, one is bad for some reason. If the problem stays with the original channels, the problem is likely in the radio programming. (Assuming the linkages are the same.) My other guesses could be one linkage has a LOT more drag in it, EXPO is not the same in both channels, and make sure there is not a premix that you are not aware of affecting the two channels.

RE: dual elevator servo
 

Spad,
I was convinced my problem was servo related.
I switched channels between servos with the same result.
I still wasn't convinced...[:o]
I took a spare servo arm and built a pointer system and checked the throws on each servo on the plane itself....
Both throws at the servo were identical.
That was the thing that convinced me it was mechanical and not electronic.
These things sure can be tuff to nail down!
JLK

RE: dual elevator servo
 

Did you get it fixed yet? I ASSUME that the servo throw can be the same with no load, but different under a load, especially if there is some internal electronic problem that prevents full torque from developing. The linkage would have to be severly different to cause this much problem.

RE: dual elevator servo
 

Spad,
It wasn't "severe"...only noticable.
Yes, I got it corrected.
JLK

RE: dual elevator servo
 

jlkonn
I did about the same thing with my .46 UCD. I also just bought a 9C and decided to assign the elevator servos to separate channels. I had some linkage issues to straighten out but they now work in sync. I'm using Hitec 625 MG servos.
K.O.

RE: dual elevator servo
 

I use Hitec Digitals and just reverse one of them with the programmer.

RE: dual elevator servo
 

I just purchased the UCD 60 anad have the same issue.Which elevator has the additional throw?

RE: dual elevator servo
 

dpitcock,
Without going out and looking I believe the left one had more throw but don't hold me to that. I think the reason they are different is that one servo is lower relative to the elevator and one linkage is quite a bit longer. I never would have suspected that it could have made this noticable difference in elevator travel but when I happened to be looking closely it was definetley there. I never noticed it flying but I haven't flown that much since getting back in to it after 15 years! I am sure when I got to serious flight trimming I would have found it.
JLK

RE: dual elevator servo
 

Mine is the left also. What did you do to correct it?

RE: dual elevator servo
 

dpitcock,
I experimented until I found a servo arm, in this case a wheel, that gave me slightly more total travel distance at the arm. This finally increased the throw in the right side until I had exactly the same throw at the control surface both sides. I tried doing it with end point adjustment at first, reducing the throw on the left side but this gave a noticeable timeing difference between the two surfaces.
JLK

RE: dual elevator servo
 

Thanks,I'll try it and get back with you.