Failed Servo question - hard to manually rotate
#1
I have a general question concerning failed steering servos. I have noticed on several (different make/model) servos that after they fail (due to accidents) that it becomes very difficult to rotate the servo (using the servo saver/horn). More specifically this isn't because a tooth or gear has broken inside the servo. It just seems like the servo doesn't rotate as smoothly or requires additional force to move.
On my most recent servo that I damaged (after hitting a track barrier head on at full throttle), the servo will still turn smoothly counter-clockwise but requires much more force to turn clockwise. Also the servo no longer responds when plugged into a known working/tested receiver. Can anyone explain what causes the difficulty in turning? Obviously something failed, but I am just curious about the actual failure.
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Here is additional information about my servo that most recently failed...
Tactic TSX20 Mini
Analog
Ball Bearing
https://www.horizonhobby.com/product.../TACM0220.html
On my most recent servo that I damaged (after hitting a track barrier head on at full throttle), the servo will still turn smoothly counter-clockwise but requires much more force to turn clockwise. Also the servo no longer responds when plugged into a known working/tested receiver. Can anyone explain what causes the difficulty in turning? Obviously something failed, but I am just curious about the actual failure.
-----------
Here is additional information about my servo that most recently failed...
Tactic TSX20 Mini
Analog
Ball Bearing
https://www.horizonhobby.com/product.../TACM0220.html
#3
Most of the time it is a broken tooth of one of the gears or a bend or broken shaft if the gears.
Indeed, you can alk all you want, only a glas bol can look inside. Open them and you will know.
But it seems you are not using a servo saver.....
Indeed, you can alk all you want, only a glas bol can look inside. Open them and you will know.
But it seems you are not using a servo saver.....
#5
I was using a Kimbrough black HD servo saver on a 1/12 GT-12 foam tire car. I always use servo savers. However if you are racing on a small indoor carpet track with wooden outer barriers you are eventually going to have a big collision. I replaced the servo with a spare I had and the car handled fine during last week's racing.
I have broken and replaced internal plastic and metal gears on servos in the past. But occasionally I have run into the issue of a steering servo either locking up or not smoothly turning. I was just wondering if anyone had any insight on what may have broken to cause such drag when trying to turn the servo spline. Maybe I bend a shaft, broke a gear, cracked the circuit board, or something else. Since the car had such a hard crash, it could be electronic or mechanical. I might take the servo apart. I will at least check the servo leads/wire to make sure those aren't damaged.
But to be honest my time will be better spent buying a similar spec servo than trying to fix the Tactic TSX20 as it is discontinued.
Thanks for the help so far.
I have broken and replaced internal plastic and metal gears on servos in the past. But occasionally I have run into the issue of a steering servo either locking up or not smoothly turning. I was just wondering if anyone had any insight on what may have broken to cause such drag when trying to turn the servo spline. Maybe I bend a shaft, broke a gear, cracked the circuit board, or something else. Since the car had such a hard crash, it could be electronic or mechanical. I might take the servo apart. I will at least check the servo leads/wire to make sure those aren't damaged.
But to be honest my time will be better spent buying a similar spec servo than trying to fix the Tactic TSX20 as it is discontinued.
Thanks for the help so far.
#6
Outside some Traxxas servos that would electronically die, every other servo that's died on me has been because of physical internal damage. As Roelof said, it's usually broken teeth on one or more of the gears. I've also had the bushing/hole in the case that holds middle shaft break.
#7
Joined: Mar 2011
Posts: 6,410
From: Austin,TX
Having experienced a myriad of failures with AGFrc servos, most of what you're looking for can be found here:
https://www.rcgroups.com/forums/show...t-AGFRC-Servos
read post #7 to see the itemized list where in this case I would be willing to bet you snapped the pin which aligns the gears... if you catch the problem early enough and replace the pin right away, then the servo can be repaired, if you continue to use a servo with a snapped pin until it locks up completely, then you may have burned the circuit board or motor, etc which the servo would not be repairable.
Good Luck!
https://www.rcgroups.com/forums/show...t-AGFRC-Servos
read post #7 to see the itemized list where in this case I would be willing to bet you snapped the pin which aligns the gears... if you catch the problem early enough and replace the pin right away, then the servo can be repaired, if you continue to use a servo with a snapped pin until it locks up completely, then you may have burned the circuit board or motor, etc which the servo would not be repairable.
Good Luck!



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