Alright, I didn't see where else under airplanes to post this, and I know this topic has been beat to death, but I just want to finally get a straight forward answer.

The set up on the elevators is this:
Futaba 9C Radio
2 Hitec 645mg servos
2 12" servo extensions
The mechanical portion matches PERFECTLY. Trust me, I have had 3 people look and measure, and even had the geometry checked by engineers at my work. The mechanical portion is spot on, so please don't tell me that is the problem .

Its a simple problem, using ailevator, if I match the high rate end point, the low rate will not match and vice versa. Plus, I have noticed a speed difference in the elevator halves. The left side(channel 8) moves slower than the right side(channel 2).

Will someone just tell me the secret to setting these up to match once and for all? I have had 4 or 5 people tell me it is so simple to do, but when I put a digital meter on their own planes there halves don't match, even though they thought they did. I'm beginning to think a matchbox is the only way to go, because a servo reverser does not have end point adjustments.

Please help me!!!!

I have experienced the problem with one servo being slower than the other when using this function, and the only fix I found (probably a better way, just this is what worked for me) was to use two auxilliary channels for the elevator halves ( 7&8 ) and slave them to channel 2.

Yep, they move slower with my 9C. MatchBox or digital Hitec servos set up with their Servo Programmer is the only solution that has worked for me. It seems like the 9C process is: CH1 then CH2 then CH3, etc. thereby making the end of the line slower than the beginning.

Fly safe, Glover

I had a similar problem with my optic 6. I had to buy a matchbox

Okay, I figured it out. Set up two airplanes last night using this technique, they all match perfectly from low to mid to high rate throws, and there is no noticable difference in speed. I did it like this:

I reset my radio so that everything was at 0 or 100%(subtrims, dual rates, end points, etc.).

I installed the servo's in the tail, and plugged the right half into channel 2, the left half into channel 7. I then set up a programmable mix to slave 7 to 2 with link and trim on. I had to use this screen to reverse one of the servos.

Using a paper protractor with a hole cut out for the servo, I used the subtrim to make sure the servo horn on both servos were exactly 90 degrees from the servo.

Next I used the same protractor and a extra long servo horn to measure the amount of throw on the right servo. I was getting 50 degrees both up and down.

I then measured my left half, I was getting 51.6 degrees up, and 53 degrees down, I then used endpoints to adjust the throw of this servo to 50 degrees to match the other side exactly.

I then set up a dual rate @ 50% to see if the throws would match, at 50% both sides matched perfectly, tryed 20%, still matched, 75%, still a match. Great, now I know my servo's are throwing the exact same amount of throw through there entire range.

I then hooked up the mechanical linkages, and since I knew my servos were perfect, I could focus on making mechanical adjustments to match them(horn placement, etc). This took about 10 minutes to do, and guess what, my elevator halves match perfectly(I use a digital throw meter, they are exact). I was so excited I immediately went to the ailerons to match them the same way, worked flawlessly again. I then went to the other plane I am working on and used the same technique, worked perfectly.

So, if you want to match any surfaces using two servos on two channels, match the servos first using a servo protractor. Then adjust the mechanical linkages accordingly, and you will be rewarded with matching surfaces. I have been fighting these set-ups for a long time now, and am relieved to finally be able to set these up with ease and to get them matching perfectly, not just close. Now... time to go fly this beast.

Thanks for posting the results. I will be using this.

Dave

Great... let me know how it works out for you. Here is the link to the protractor I used: http://www.rcuniverse.com/magazine/r...protractor.pdf

Bless you. I have to do the same thing for the first time on my G.P. Ultimate and was debating whether I should get a mixer or try the "built-in" radio mix.

If you haven't already, check out http://www.futaba-rc.com/faq/faq-9c.html for some helpful tips not in the manual. Also, Harry Higley's "RADIO Programming Futaba's 9CA" has some great tips and clear explanations - but not for dual elevators (Elevons, yes).

Here the specific FAQ for dual elevator servos -http://www.futaba-rc.com/faq/faq-8u-q586.html Pretty un-helpful if the endpoints & sub-trims are against you as in your case.