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Author Topic: Servo Reversing  (Read 2996 times)

Bob K

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Servo Reversing
« on: November 24, 2012, 11:18:38 am »

A question for our technical colleagues.  I am opering two servos, one for a regular stern rudder and another for twin bow rudders.  Ideally I would like to operate both on the same Tx channel with a Y lead so they operate in unison.

However, I need to reverse the bow servo rotation.  I believe this is sometimes done on RC aircraft for separate aileron servos.  Two possible methods:
 
1)  Open up the servo, reverse the two motor leads, then reverse the two outer potentiometer wires. Looks very fiddly.
http://www.youtube.com/watch?v=EK_FdRTenl0
 
2)  Hobby King do a very cheap servo reverser lead, but how well do these work?
http://www.hobbyking.com/hobbyking/store/__17033__Turnigy_Servo_Signal_Reverser.html
 
Suggestions  please.
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Tug-Kenny RIP

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Re: Servo Reversing
« Reply #1 on: November 24, 2012, 11:26:22 am »


Follow the film and it's a piece of cake.  Not much to go wrong.


Ken

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U-33

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Re: Servo Reversing
« Reply #2 on: November 24, 2012, 11:29:40 am »

Turn the bow servo through 180*?
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triumphjon

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Re: Servo Reversing
« Reply #3 on: November 24, 2012, 11:29:57 am »

silly idea but can you not turn the servo on its mountings in the bow area ?
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Circlip

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Re: Servo Reversing
« Reply #4 on: November 24, 2012, 12:33:22 pm »

Holes on servo disc on one side of the C/L pull the linkage while the ones on the other side push ? So for two servos coupled with a Y lead, you should be able to get "Reversed" operation by moving the linkage only.
 
  Regards  Ian.
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Subculture

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Re: Servo Reversing
« Reply #5 on: November 24, 2012, 12:33:40 pm »

Reversing the motor wires and pot is not generally possible on a lot (most) of modern servos because the motor and/or pot is directly connected to the servo pcb (e.g. Futaba servos), unlike most earlier servos which were hooked up with flyleads. This makes them more rugged and less prone to failure when installed in models with a lot of vibration, but it does make them trickier to tweak and service sometimes.

If the servo is installed with flyleads, it's a fifteen minute job to rewire it and it's the method I would choose. Failing that the servo reverser widgets should work just fine.
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Bob K

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Re: Servo Reversing
« Reply #6 on: November 24, 2012, 01:01:30 pm »

Thank you guys.  I think first I will see if the servo can be opened and check inside to see if there are flyleads accessible.  Failing that I will try the Hobby King reverser widget.
 
Unfortunately the servo in question has a toothed belt drive fitted so crossing over the linkage arm is not an option in this case.  Otherwise that would have been the easiest way.  I could have crossed over the arm on the other servo but then both would be reversed rotation, in which case reversing that channel on the Tx may do it.
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john s 2

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Re: Servo Reversing
« Reply #7 on: November 24, 2012, 03:37:31 pm »

Action also sells a servo reverser. His one is ajustable and did the job for me. John.
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Bob K

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Re: Servo Reversing
« Reply #8 on: November 24, 2012, 04:41:25 pm »

That looks interesting John, if you mean their P105.  I need to speak with Dave at ACTion.
We only have up to Tuesday, as after that it all starts moving across to Component Shop.
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ardarossan

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Re: Servo Reversing
« Reply #9 on: November 24, 2012, 04:46:01 pm »

Mtroniks also produce a Servo Reverser which is advertised as being waterproof. Details and dealer locations at this link:

http://www.mtroniks.net/details1.asp/ProductID/278/Servoreverser.htm

Andy
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kinmel

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Re: Servo Reversing
« Reply #10 on: November 24, 2012, 06:12:18 pm »

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