Iflyit

My Feedback: (512)

I am setting up my Hanger 9 Edge and this is the first time I have setup a dual aileron servo system for the ailerons.
I am using Hitec digital servos and I have the programmer for them but I cant seem to get them equal without humming badly. Anyone have a setup procedure?

DMcQuinn

My Feedback: (13)

My experience with two digital servos on one surface is that they will always buzz a little more than if there is only one servo. Even with the programmer, I think you always have a little bit of fighting going on. I used an ammeter to measure the current of one servo (with the second servo unplugged) and measured the current flowing to the one servo. Then I plugged in the second servo to see how much more current the first servo was now drawing. It was a very small increase in current, so I am not too worried. I have been flying a 35% plane this way for 4 years now. My servos are JR DS 8411. Obviously you want minimum buzzing, but I would not fret too much over this.

TJPro35

You will always get buzzing because of the weight of the control surface pushing down on servos...normal. One of the ways I check for buzzing/fighting is bring the control surface vertical so there is no weight pushing down. If you get buzzing in this position, you know you got some fighting and reprogramming is required.
As far as programming....Everybody has thier "special" way of doing this. First thing is make sure you have the geometry as close as possible on your servo arms and reset all your servos.
The way I do it is disconnect outboard servo. Program inboard servo and program center first. Then adjust your end points by measuring the throw up and down....millimeters are best source of measurement. If you have a futaba, add about 3mm more then you want.
Disconnect inboard and do the same for outboard using the same mm measurements. Your numbers on the programmer will be different for each servo. Don't match this numbers with each servo!!. Always do the center first, then right/left. If you adjust center after you adjust end points, you will have to re adjust end points.
Hope this helps.

TJ

bentgear

Iflyit, sent you a PM with a link that might help you out.

Ed M.

Iflyit

My Feedback: (512)

Didn't work for some reason, sent you my email address to send it to.

sillyness

My Feedback: (25)

Stand the wing on its leading edge while programming. This should eliminate most of the surface weight buzzing. Every time I make an adjustment I gently move the surface back and forth. If I can feel it move slightly (the slop in the servo gears) then the surfaces are well matched. If the surface doesn't want to move at all, then the servos are fighting each other. Ideally you want the surface to bump against the gear train of both servos at the same time in both directions... that's a slick setup and is very achievable IF all the dimensions in the two linkages are exactly the same (servo arm length, servo arm center position, control horn distance from hinge line, control horn length, and pushrod length).

JoeAirPort

My Feedback: (41)

Another thing you can do is to remove one side of both linkages. Have someone hold the tx and give it full right. Push the aileron with your hand until it lines up with both linkages. If both linkages will not fit into the open holes (test fitted), one servo can be adjusted a click or two + or -. Do this for the center and both end points. I did this today and it worked out great. You can only get it so close with the little paper protractors. When I did my final adjustments with the programmer, I couldn't figure out which direction to tweek the servos to get rid of the buzzing. So doing this made it really easy to see which one was off by a little bit.

Stick Jammer

Good advice by the others. I'll add one more item.
What do you have the deadband width of the servos set at? Setting the deadband at the lowest number can cause excessive humming with dual servo surfaces. I found that setting the deadband at 2 eliminated a lot of buzzing in my set ups.

bentgear

Iflyit, don't know how I forgot about this link, Desertpig did a great article on matching elevator halves with the programmer. Lots of good info, not just for elevators.

[link]http://www.rcuniverse.com/forum/m_2614917/anchors_2617954/mpage_1/key_/anchor/tm.htm#2617954[/link]

Ed M.

Iflyit

My Feedback: (512)

Thanks, the linkI was sent from down on the deck explained everything that I needed to know.

Geistware

My Feedback: (16)

While this response is not popular, ditch the programmer and get a matchbox.
I tried to use the programmer for 3 weeks and never got it to work right.
With the match box it is easy. Measure the current on one servo, and adjust the end point on the other for minimum current.
Do this in both directions and you are done, finished, and ready to fly!

mglavin

My Feedback: (31)

While your approach works and some may find it easier to accomplish said goal, it is far from utilizing the inherent design advantages of Hitec's programmable servos and introduces another failure mode too. Not to mention; ancillary servo matching devices do not allow the user to obtain linear travel resolution or match the TX to their repective model setup. These devices are simply a work around approach for the short comings of the TX and servo alignment.

If you were unsuccessful with the programmer you must have over-looked and or mis-understood something. What was the specific problem you incurred that you were unable to work around?

JoeAirPort

My Feedback: (41)

The only thing I can think of that Geist might be refering to is that the Hitech servo programmer's output pulse does not correspond exactly to the Futaba tx/rx when setting centers and end points. But there is an easy work around. Just keep the programmer and tx/rx both powered up and keep plugging the servo back and forth. Tweek the programmer to get it exact. After a few tries it lines up dead nuts. I just set up my DPM Edge 540 26% with one 5945 on each elevator half. I also did two 5245's on each aileron. The one thing I wish the Hitech programmer did was to display the center and endpoints (without having to change them). One thing I think is totally cool about the Hitech programmer is that with the Flaperon feature, you can plug in your channel 2 and 8 into the programmer to make sure that your rx output pulse is identical on both channels. This is a great trouble shooting feature. I discovered that my endpoints on the tx were not the same (my fault).

mglavin

My Feedback: (31)

This is a common phenomena and is not a problem with the programmer and is not specific to Futaba radios, in fact any TX may suffer from these shortcomings.

The proper method to match your servo(s) to any TX is to utilize an iteration programming procedure. This will assure the servo rests at neutral and end-points exactly as the TX in use dictates. It would be nice if every TX in use was perfectly aligned, tuned, adjusted and tweaked to transmit 900-1500-2100us with the trims zeroed and end-point percentages equal. Alas its not likely and very rare. There are simply to many factors at play. Electronic and mechanical component tolerances play a large factor as well as the OEM acceptable tolerances for transmitting the desired pulse widths...

FWIW: For the most part the RX plays no part in this phenomena.

The programmer will display the center and end-point programmed parameters while in the programing mode. Utilizing iteration you would note these settings and work from them subsequently.