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Depending on where you sail
(fresh or saltwater) you may run into problems with your servos.
The primary problem is that water gets into the servos and can
cause a number of problems; the most common is the fouling of
the potentiometer witch can be seen as a twitching of the servo
or a failure of the servo all together.
Without getting too technical,
the potentiometer is the device directly connected to the output
arm of the servo that tells the servo where the arm is, compared
to where the transmitter is telling it to be. If this device
becomes fouled and communication breaks down or becomes
intermittent, then the servo bounces back and fourth trying to
agree with the transmitter, or it stops completely.
BEFORE you try
to repair your servo, make sure you have made every effort to
check that the problem you are having is not one of the
following:
-
Bad Crystal
- Switch frequencies and check the servo.
-
Corroded
Connections - Check/Clean the servo connections
-
Low Battery
Power - Change to new or freshly charged Batteries.
-
Faulty
Receiver or transmitter - Try switching the serve to another
radio.
If after
checking the above and you are still having problems, try your
local hobby shop. If you are still out of luck only then try the
following. This technique is my solution and is not to be
rushed. If done incorrectly you can totally destroy your servo,
so proceed at you own risk and TAKE YOUR TIME.... |
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| 1. Remove the
bottom case screws |
2. Remove the top
case cover |
3. Remove the
gears and shafts - Take note of the
placement of each gear. This exposes the Pot nut. |
4. Remove the
potentiometer nut and washer |
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| 5.
Gently loosen the circuit board and
move out of the way exposing the pot. Take
note of the orientation of the pot. |
6. Press the shaft
(top) of the pot. down, forcing the pot into the case. |
7.
Carefully lift the pot. out of the
case. Mark the pot. top and bottom for
orientation. |
8. There are three
"hold down" tabs, carefully pry
each tab up. |
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| 9. Separate the
two halves of the Pot. exposing the contact brushes |
10. Using a soft
cloth lightly wipe the surface of
the disk. Do not touch the brushes.
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11. Put the Pot
back together checking the orientation
marks and bend the three tabs back into place |
12. Insert the pot
back into the case, reset the orientation
(see#5) and insert the washer and tighten down the pot
nut. |
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| 13. Carefully
reinsert the circuit board, align the servo wires and reseat the
case bottom. |
14. Turn the case
upright |
15.
Carefully reinstall the gears
making sure they are seated and turn freely. |
16. Screw in the
bottom case screws. |
Plug the servo back into your receiver and give it a try.
Not all problems with servos can be fixed with this method but I have found that it has cleared up a number of twitchy servos.
If all else fails give your hobby shop a call and purchase a new servo.
I hope this page was of some help.
