Servo question

One of the four servos in my wing seems to have a mind of it's own. It is the right aileron servo and it is a standard size two ball bearing servo. If
I give it input (stick movement) mostly to the endpoint and release it will move in the correct direction, but it appears further than my programmed endpoint. Perhaps to my high rate, maybe further even though I'm on low rates. I have swapped ports on the receiver, as well as disconnecting various combinations of flaps or ailerons and also substituted another receiver. I connected all 7 servos on the plane and the result is the same servo having a problem. Someone at the field mentioned I may have a dirty "pot" and it needs to be cleaned. Does anyone agree? If that might be correct, I know not to use just any cleaner solvent and there is specific cleaner solvents for servos. Is there any reasonable substitute maybe found around a house or shop? Do you think I just need to give it up and replace the servo? TIA Howard
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"Howard" <howardh1951-at-hotmail.com> wrote

Any good electrical contact cleaner.

How much does the complete plane cost? How much does a new servo cost?
You make the call. I know what I would do. It really is a no brainer, because no contact cleaner is going to have a guarantee worth the price of the plane.
--
Jim in NC



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An excellent lubricant and cleaner is CRC 2-26. You would think its much like WD-40, but is safe for plastic and improves electrical properties. g
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Some info on servo issues and how to solve them:
http://www.rcgroups.com/forums/showthread.php?ti9810
"Howard" <howardh1951-at-hotmail.com> wrote in message

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"Howard" <howardh1951-at-hotmail.com> wrote in message

I would replace the servo.
I have gone the route of taking servos apart to clean them when they gave trouble but I never found that it was worth the trouble in the long run.
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Everything in a plane has an expiration date, engine, battery, receiver and servos. The engine is the only one of these things that I'll fix when it starts giving me trouble. The others just aren't worth my plane, and the engine is also the only one of these that can fail in flight and still give me a high likelihood of a saving the plane. Your servo has reached it's expiration date. Do yourself a favor and replace it. You'll never know if you saved your plane from a crash, but do you want to take that chance? Just my $0.02. 42
"Howard" <howardh1951-at-hotmail.com> wrote in message

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| Everything in a plane has an expiration date, engine, battery, receiver and | servos. The engine is the only one of these things that I'll fix when it | starts giving me trouble. The others just aren't worth my plane, and the | engine is also the only one of these that can fail in flight and still give | me a high likelihood of a saving the plane.
Actually, the same goes for the throttle servo.
If you have an iffy servo and insist on using it (not a good idea, especially since they're only like $9 new for reasonable quality standard servos) use it on the throttle. That way, if it misbehaves, then you just can't throttle up, or can't throttle down until you're out of gas ...
If it's a four channel plane, the rudder servo is less critical than the others as well, but if it gets stuck all the way to one side, it might make the plane impossible to fly. Just replace it.
Whatever you do, always make sure that your elevator servo works 100% ! And the same goes for your aileron servo, if there's only one. If there's two, perhaps there's a little room for one not to work -- but not much.
If you're on a budget, and it's a 0.40 or similar sized engine, these servos --
http://www.servocity.com/html/hs-311_standard.html
are only $9 each and are good quality. Have a few spares on hand so you're not tempted to fly with an iffy servo ...
--
Doug McLaren, snipped-for-privacy@frenzied.us
I can't take his money. I can't print my own money. You want me to
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The most likely answer is a bum servo. However, it you are using servo extensions, and those extensions do not have gold plated connectors, the resultant poor connection will manifest itself in problems similar to what you are describing.
"Howard" <howardh1951-at-hotmail.com> wrote in message

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I have had this too(extension was it). You can trouble shoot changing out extensions and servos, or just replace from RX to control surface. mk
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If you do decide to repair/clean the pot, I would suggest swapping the servo with the throttle servo.
Then, if the worst happens and it fails in flight, you just have to fly around for a while with no throttle control, and do a deadstick landing after all the fuel used; better than an aileron stuck up/down
Trefor

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wrote:

Somehow putting a servo with a bad pot causing it to range higher than expected into throttle service doesn't sound like a great idea...
/daytripper (but that's just me thinking out loud ;-)
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I agree
What I said was if you repair/clean it, swap with the throttle
I didn't think I needed to spell it out, that if the "repair" didn't work then ditch the servo
OK?
Cheers
Trefor

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I have had to fly around waiting to run out of fuel, only thing was, it was a contest event and everyone was watching and waiting for the next event. I've thrown away more servos since then. mk
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Ha Ha Yes, I know. It ain't that easy, especially when the throttle is stuck on wide open.
You try all those manouvers where it usually cuts out, stall turns, ouside loops...etc
What happens?
The engine performs brilliantly, never misses a beat
So, you have to suffer the embarrassment of screaming round the sky by yourself, (No-one else in their right mind is going to fly while you're hogging the airspace) until it finally cuts out!!
Trefor

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no brainer. throw that servo away.
"Howard" <howardh1951-at-hotmail.com> wrote in message

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Jim wrote:

No: strip it for spare gears at least.
And the electronics and motor can be handy too.
You can replace the motir with an LED and dide and resistor in series, and make a landing light..on a spare channel. Just replace the pot with two resistors.

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A new servo it will be. Thanks for all the input. Howard

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I have had similar problems and traced them to a cheap (or failing) extension. It has to do with the contacts beginning to fail. However, it is also possible the servo itself is bad. Replace the servo AND the extension.
"Howard" <howardh1951-at-hotmail.com> wrote in message

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