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View Full Version : Help! Servo reversing "Y"-cable?

ScYcS
Aug 07, 2009, 09:19 AM
I ordered a FA/18 Airframe only version, made by J-Power and it uses a Servo reversing "Y" cable to make the elevator work properly. This cable does not come in the airframe only version and Hobby-Lobby does not offer such a cable?!?

How can anyone build this model without the reversing "Y"cable?!?!
iflytailies
Aug 07, 2009, 11:23 AM
just put the servos in in the same direction

http://iflytailies.jimdo.com/
ScYcS
Aug 07, 2009, 11:32 AM
Then i would have to cut foam out and the model would look ugly.....

Also, i think that's not even possible in the FA/18 as they stick out on the sides, so i i'd reverse them this way, they'd point into the fuselage.
iflytailies
Aug 07, 2009, 11:47 AM
look for "MIRACLE Y ™ MK-II with buffer" here:

http://www.maxxprod.com/mpi/mpi-5.html
ScYcS
Aug 07, 2009, 11:50 AM
yeah i know about the product but it's $26 shipped for a cable. The ARF of these comes with a simple cable so i assumed HL would have a replacement in stock for less than $20?! It's only a cable afterall!!!
The Don
Aug 07, 2009, 11:53 AM
You have to mount one sevo horn so it points up and the other one so it points down and that will do the reverse for you.

Don
The Don
Aug 07, 2009, 11:56 AM
Like this:

http://site.nitroplanes.com/EDFnew/arttechf18a.jpg

http://site.nitroplanes.com/EDFnew/arttechf18d.jpg
The Don
Aug 07, 2009, 12:02 PM
The other option is to make your servo a reverse servo by opening it up and swapping the motor wire polarity and the two leads on the pot. That is the safest as if your reverse Y harness fails the you are screwed. This way a normal Y harness is all you need.

Don
ScYcS
Aug 07, 2009, 12:26 PM
Like this:

http://site.nitroplanes.com/EDFnew/arttechf18a.jpg

http://site.nitroplanes.com/EDFnew/arttechf18d.jpg

EXCELLENT!!! Thanks a whole bunch for the pics, i just couldn't visualize it, but that totally clears it up. Just need a normal "Y" cable then.
KrazyKyle
Aug 07, 2009, 12:47 PM
I ran into the same problem on my J-power A-7. They supply a regular Y-harness, but one elevator servo is a "reverse". (BTW if you can open that little puppy up and swap wires, you have better eyesight and a smaler soldering iron than I).
If I can't get a replacement for the defective servo from HL, I'll put in a regular one and plug it into an extra channel and mix it that channel with elevator (resisting the temptation to mix in "tailerons"). Similar to separating the wing servos for flaperons.
ScYcS
Aug 07, 2009, 12:51 PM
I'm actually considering totally leaving the elevator servos OUT and just using the wing servos as Elevons.
WTFLYR
Aug 16, 2009, 12:14 AM
You have to mount one sevo horn so it points up and the other one so it points down and that will do the reverse for you.

Don
Exactly. I did that with a GWS15 also. Better than the added weight of a reverser. I would do it to any of these jets where it is possible.