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Old 10-04-2019, 07:45 AM
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Ok.... if the motor still works and the case is not cracked. You can find a new set of gears and rebuild it.. I have done several 8911’’s in the past with good results.. I think I bought the gears from AmainHobbies or Chief Aircraft talk to Steve from Chief he will know what you need.
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Old 10-04-2019, 08:35 AM
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Yes, if the motor is still working you can order a complete new gear set.

https://www.deeforce.net/product-pag...-8611a-and-etc
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Old 10-04-2019, 11:07 AM
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Quote:
Originally Posted by JBaynes05 View Post
Heres what I'm working with.

The issue is this. The servo gears are junk! Just stating the obvious here.

Look at your servo output shaft gear teeth. There is a good chance that 50% of those teeth are stripped. Then, look at your 3rd pic, you posted. You have shreds of gear teeth embedded into those gears too!

What in all things that are not holy happened to this servo?? A servo just does not strip gears without some serious force acting on it....

When you buy a new gear set for this servo, splurge and buy the aluminum top case for it too. The top case will not keep the gears from stripping again, inlieu of a crash or a heavy force acting upon it. The aluminum top case will not allow the gear pins holes to wear out.
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Old 10-04-2019, 01:14 PM
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Quote:
Originally Posted by Bunky F. Knuckle View Post
The issue is this. The servo gears are junk! Just stating the obvious here.

Look at your servo output shaft gear teeth. There is a good chance that 50% of those teeth are stripped. Then, look at your 3rd pic, you posted. You have shreds of gear teeth embedded into those gears too!

What in all things that are not holy happened to this servo?? A servo just does not strip gears without some serious force acting on it....

When you buy a new gear set for this servo, splurge and buy the aluminum top case for it too. The top case will not keep the gears from stripping again, inlieu of a crash or a heavy force acting upon it. The aluminum top case will not allow the gear pins holes to wear out.
Okay. I will look into it.
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Old 10-04-2019, 04:26 PM
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That motor could also be toast after all that work is was doing smashing that gearrain up
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Old 10-04-2019, 04:51 PM
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What guarantee is there that the motor didn't seize and burn up as well? Anyone that can tell yay/nay about the health of the motor from that pic have a better screen than I do. Does it pass the smell test?
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Old 10-04-2019, 05:13 PM
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What guarantee is there that the motor didn't seize and burn up as well? Anyone that can tell yay/nay about the health of the motor from that pic have a better screen than I do. Does it pass the smell test?
thats kinda my point.

the op should plug the servo into a test meter or his rx to verify, then play with the pot tab to confirm both directions. simple enough.
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Old 10-04-2019, 05:43 PM
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Originally Posted by JBaynes05 View Post
Go ahead... I am new to giant scale. I need all the help I can get.
The condition of your servo has nothing to do with it being from a giant scale plane. Any servo that has a stripped or busted gear(s) can lock up, or smoke(a term used when you get magic smoke out of the servo).... whether a plane is big or small. Some servos are worth fixing if possible, some you just throw away and buy a new one. That JR servo is one that if it's fixable, you fix it.

As mentioned, your motor might or might not be toast... depending on how long it was stressed, and how much stress it was under. Look for any sign of smoke damage where it was mounted(not kidding, ask me how I know).

If you're not sure about all of this stuff, it might be best to just buy a new servo, maybe... but I think what's going on is it's obvious to those with experience as to what happened.

Although it doesn't happen to often, stripping a servo gear does occur for different reasons. They do take the lions share of the load in many ways.

I suggest you double check each servo in that plane, and make sure they're all smooth with no glitches in the gear trains... while at it, double check all your linkages and hinge lines to make sure there's zero binding. That servo stripped it's gear for a reason.. maybe it was worn.. maybe it was trying to move a stiff surface for too long.

Don't take anything for granted with the mechanics of these planes. I recently started a poll/thread about lubing servo gears, it's something I've pondered for a while now. Not saying a lack of lube caused your problem, but you might want to check out that thread when you reassemble your servo.. and you'll probably want to lube those gears.
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Old 10-04-2019, 07:05 PM
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Originally Posted by DGrant View Post
The condition of your servo has nothing to do with it being from a giant scale plane. Any servo that has a stripped or busted gear(s) can lock up, or smoke(a term used when you get magic smoke out of the servo).... whether a plane is big or small. Some servos are worth fixing if possible, some you just throw away and buy a new one. That JR servo is one that if it's fixable, you fix it.

As mentioned, your motor might or might not be toast... depending on how long it was stressed, and how much stress it was under. Look for any sign of smoke damage where it was mounted(not kidding, ask me how I know).

If you're not sure about all of this stuff, it might be best to just buy a new servo, maybe... but I think what's going on is it's obvious to those with experience as to what happened.

Although it doesn't happen to often, stripping a servo gear does occur for different reasons. They do take the lions share of the load in many ways.

I suggest you double check each servo in that plane, and make sure they're all smooth with no glitches in the gear trains... while at it, double check all your linkages and hinge lines to make sure there's zero binding. That servo stripped it's gear for a reason.. maybe it was worn.. maybe it was trying to move a stiff surface for too long.

Don't take anything for granted with the mechanics of these planes. I recently started a poll/thread about lubing servo gears, it's something I've pondered for a while now. Not saying a lack of lube caused your problem, but you might want to check out that thread when you reassemble your servo.. and you'll probably want to lube those gears.
So I checked it out... motors toast. Might as well just buy a new one. Thanks for the help guys.
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Old 10-04-2019, 09:47 PM
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Check the other servos in your plane before you buy just one servo. Also, one of these servos might be tough to get, as most sellers sell pairs or several at a time.... so be patient.

If you have other 8711's on your plane, you'd be good to have a few spares laying around.... and I would only use a matched(same model/brand) servo in it's place if it was on say an aileron or elevator, or any surface that there's multiple servos.

Example, Say its an aileron servo, and you have another 8711 on the other side, either replace the bad one with another 8711, or swap both aileron servos for matching units... of whatever brand/model (hope that makes sense).. The idea is to keep things balanced. ..

I'm not sure who services or repairs JR servos these days, but FYI there are other mainstream brands that also do repairs(not JR though)...

I wonder if D-Force is doing JR repairs... but I don't know... I've heard a few different things.
In the days of when JR was in full business, your servo could literally be repaired for a reasonable price, but again I'm not sure of the status of any JR repairs going on.

Good luck with it.
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Old 10-05-2019, 03:40 AM
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So I checked it out... motors toast. Might as well just buy a new one. Thanks for the help guys.
Where do you fly.. it says you are close to me according to the site.. if you want help with this I can give you a hand before you drive yourself nuts! Lol just inbox me
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Old 10-05-2019, 11:24 AM
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On the same topic, let's say this was a rebuild moment. Any servo that has that much damage (or any, really) and appears to be Ok, it's best to test it in a beater or throttle or maybe even on a rudder. That way if it was hurt but only showed that in the next flight it wouldn't be crashing a 30+% bird. Luckily the motor damage was enough to not risk it but some may be damaged yet still work for now. Always do the smell test!

And the "look for burn damage nearby" comment was valid! I cooked one anwhile back and still have the smoke stain showing from inside the wing covering. I learned when balancing servos to be careful when picking the channels... I watched the amps go from about 1.75 to around 7 in about 2 seconds since I was adjusting the wrong one. They didn't play well at even a steady 2ish amp load. If it smells bad, it's hurt at best.
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Old 10-06-2019, 08:27 PM
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Well, the gears are stripped, might be salvageable with replacement gears set
File 13 means the trash can
Also known as the round file cabinet
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Old 10-07-2019, 05:18 PM
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Originally Posted by boothg-3 View Post
Well, the gears are stripped, might be salvageable with replacement gears set
File 13 means the trash can
Also known as the round file cabinet
Read post #24.
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Old 10-08-2019, 10:57 AM
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Read his post where he asked what file 13 was
I answered that question
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