[Terra Firma]

I had a exceptional crash(pilot error) with my super stick and Spektrum dx7 radio.The engine was damaged, the plane a right off and the receiver case was cracked. heck even the switch harness and a servo connection was damaged.
The receiver still worked but I mailed it to horizon hobby to have it checked over and have the case replaced. Now a club member who saw the crash said today he would NOT re-use the servos as he felt they could be un-reliable.
i bought a new receiver to keep flying buy now i am hesitant to use the servos.....the radio gear was purchased april 08 so it isn't worn out by any means. Is this normal to question servos after a crash??? i can see stripped gears being an issue but i thought the electonics would be bullet proof. Gee my daughters cell has been through the wash twice and it's still going strong!
Thanks Rc Canada!

[benjhind]

You DEFINITELY should question the servos' functionality. After a crash I give my servos a good look over, make sure they are moving properly and center well. Then I move them through their whole length of travel while applying a healthy amount of resistance with a finger. If they pass these tests, they're good enough for my planes, but I'd still be nervous putting them in something quite pricy.

Just two cents from a guy who likely crashes more than he should

[luv2flyrc]

check to see if they still work, if yes, you're good to go. Generally it's only the gears that get damaged.

Mike

[Wayne_K]

I've had servos that looked and felt OK after a nasty crash. Upon applying some pressure to the servo arm, rather than turn the servo motor, the gears just clicked and I could move the arm about 45 degrees. Then I could click it back.

Would have looked normal if I didn't try and move the servo with my hand, with a bit of force.

I'd be wary.

W

[Midair]

Hello Terra Firma:

In consideration of your flying mishap, your user name appears to be quite appropriate But, seriously, I'm sorry to learn about your accident. Regarding your original question, in addition to what the guys before me have recommended, there is one more test you might consider if you're concerned about the electronics within the servos - what I have done in the past is to connect all the servos to the receiver, power up your system and lay the works on something that vibrates - like a scroll saw. Turn on the saw and exercise the servos and check to make sure they still respond properly - no dead spots, full movement etc. The vibrations from the saw may cause a servo to respond intermittently if any of the components are damage or solder joints have failed.

Peter

[DO335]

Originally Posted by Terra Firma

The receiver still worked but I mailed it to horizon hobby to have it checked over and have the case replaced. Now a club member who saw the crash said today he would NOT re-use the servos as he felt they could be un-reliable.
i can see stripped gears being an issue but i thought the electonics would be bullet proof.

If the electronics in the servos are bulletproof, why are they not in the RX as well? Why would the RX need a good once over and the servos would not? You even said it worked.

Guess what happens to servos, especially digital, in a crash when they are cranked to max throw, sitting under a pile of rubble for who knows how long, with the power on, until you rescue them? The elctronics get fried. And then guess what happens at some point when you put them into another plane? "check to see if they still work, if yes, you're good to go. Generally it's only the gears that get damaged.

Mike "

WRONG!!

They work when you start and crap out during the flight. Send luv2flyrc the bill for your demolished plane when that happens since he sent you faulty advice.

Remember, the RX worked too, by your own statement, so luv2flyrc's logic does not hold up for it. Why is it not "good to go" too if it works?

You're playing with fire with those junk servos. Of course, you could always do as others I've seen and put them up for sale on RCC as having little air time, with no disclosure of the crash.

That begs the question: Would you buy such servos, knowing their history, and confidently put them into your new plane or would you jump all over the guy selling them, telling him how he is cheating you or that his servos are worth nothing?

[luv2flyrc]

Originally Posted by DO335

Guess what happens to servos, especially digital, in a crash when they are cranked to max throw, sitting under a pile of rubble for who knows how long, with the power on, until you rescue them? The elctronics get fried. And then guess what happens at some point when you put them into another plane?
Mike "

Send luv2flyrc the bill for your demolished plane when that happens since he sent you faulty advice.

Tell u what DO335, why don't u send me all your crashed 8611, 8711's that you are going to discard and I'll happily check the gears and go fly them.

In 15 years of flying , the last 5 with fairly large planes 33-35%, I have never had a servo crap out yet in flight, gears yes, servo motor no. Crash or no crash.

The four jr8411's that are in the wings of my 35% Carden right now, were in the wings of my H9 Suk that plummeted to the ground when the wing folded up during a parachute 4 years ago. Still performing flawlessly.

Check the servo's, make sure they work as they should, go fly. What do you think the service dept is going to do to them?

BTW, most receivers survive a crash just fine too

Mike

[Terra Firma]

Boy...i sure caused a ruckus!
I will email horizon hobby and see if they will inspect and test them. i sent the receiver in for repair because the case was cracked and an antenae was missing. i like the vibration test....if there is an open circuit anywhere from a fractured solder joint then it should show up. i think visually inspecting the gears is a good idea as well.
Maybe I'll put the servos in a S.P.A.D.

[benjhind]

Originally Posted by Terra Firma

Maybe I'll put the servos in a S.P.A.D.

Smartest thing I've heard all day

[Billpilotca]

Visual inspection of the servo gears is always a good idea. I check them out with another receiver and make sure they operate and stand up to some resistance on the arms in either direction, but I also always take the time to pop them out of their cases (4 screws to be undone). Sometimes it is hard to detect stripped or broken gear teeth by feel alone. It is one more check that is easy to do. If I have doubts about any of them I put them in a lower cost / higher expendability test bed plane and fly the blazes out of them to see if they are working properly.

You have to judge the risk in each situation. Personally I would not just pitch them in the trash, but check them out and try to minimize your concern before you put them into another valuable aircraft.

Bill