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-   -   Setting up an aileron wing (http://www.Wattflyer.com/forums/showthread.php?t=73010)

DavidR8 01-20-2014 11:43 PM

Setting up an aileron wing
 
This feels like an embarrassing simple question.
What is the ‘standard’ practice for setting up a plane is setup with separate aileron servos? I'm using a Futaba 7C radio.

To my mind, there seems to be only two connection options:
Use a Y-harness into channel 1. I believe this requires flipping one of the servos: both arms either face out or in so that they move in opposite directions.
Assign the second servo to a different channel and reverse that channel.

Obviously the Y-harness is more simple but I'm kind of assuming it precludes flaperons.


Or am I missing something?

kyleservicetech 01-21-2014 12:15 AM

Quote:

Originally Posted by DavidR8 (Post 937661)
This feels like an embarrassing simple question.
What is the ‘standard’ practice for setting up a plane is setup with separate aileron servos? I'm using a Futaba 7C radio.

To my mind, there seems to be only two connection options:
Use a Y-harness into channel 1. I believe this requires flipping one of the servos: both arms either face out or in so that they move in opposite directions.
Assign the second servo to a different channel and reverse that channel.

Obviously the Y-harness is more simple but I'm kind of assuming it precludes flaperons.


Or am I missing something?

Yup
Standard configuration is a two servo system with a "Y" harness. As you indicate, that requires both servo arms to either point away from each other, or toward each other.

If your radio has mix capabilities, there are advantages to using a separate channel for the second aileron. Such as simple neutral adjustments, travel amounts, and if desired, flaperons.

Larry3215 01-21-2014 01:47 AM

Check your manual to be sure, but IIRC Futaba assumes you will plug in the right wing servo to the aileron channel on the RX. The left side servo goes into one of the aux channels.

It helps to do this if you are using the built in pre-mixes for flaperon, crow etc.

DavidR8 01-21-2014 02:21 AM

Thanks gents
 
Happy to know that I'm managing to figure this stuff out...

I'm in Victoria Larry, how's your weather down in Gig Harbour?

Larry3215 01-21-2014 02:36 AM

We actually got a bit of sun today. Thats been a mighty scarce commodity for the last few months!

Mostly its been rain and overcast for what seems like forever! At least we have had little to no snow so far this year.

maxflyer 01-21-2014 09:57 PM

If this is a first aileron model you might consider going with one servo to operate both ailerons. Many 3D models use a setup like this. My scratchbuilt aileron trainer works this way. Saves weight. Saves a few bucks. Simplifies installation, and lets you get away with using lower-powered ESCs, as you should consider adding an external UBEC when you move beyond 3 servos.

DavidR8 01-21-2014 10:34 PM

Not the first plane, just trying to understand the setup of a built Fun Cub I bought. And trying to reduce the rat's nest of servo wires under the wing.

It also has flaps. Because these move in the same direction, would a a y-harness work for that pair of servos?

Not sure if anyone has a Fun Cub but IMHO the space for the wiring is very tight. When the model is built, the underwing opening is perhaps 1.5" in diameter, and access from the under the fuselage is equally restricted.

Perhaps that's why mine was built with such long extensions... so a person could drag the RX out of the bottom

hayofstacks 01-21-2014 10:46 PM

if the servos move the same direction you can use a regular y-harness. if you have a 7 channel radio you can use different channels for each servo and set up crow if you would like.

if you need to reverse a servo, you need a reversing y-harness or if you want, you can reverse two wires on a servo extension or make your own.

Larry3215 01-21-2014 11:45 PM

Quote:

Originally Posted by hayofstacks (Post 937754)
if the servos move the same direction you can use a regular y-harness. if you have a 7 channel radio you can use different channels for each servo and set up crow if you would like.

if you need to reverse a servo, you need a reversing y-harness or if you want, you can reverse two wires on a servo extension or make your own.

Not a good idea.

Reversing two wires on a servo extension will either do nothing or burn up the servo circuit board or short the rx or it wont send the signal to the servo or more than one of the above - depending on which two wires you switch :)

The circuit board inside requires that the POS and NEG and signal leads stay exactly where they are.

You have to open up the servo case and reverse the wire connections to the servo motor itself. Sometimes thats easy to do and sometimes not so much.

cyclops2 01-22-2014 01:10 AM

Save a perfectly good servo from never being reassembled or correctly retimed again.

Buy the made up part to do the job.

Rich

DavidR8 01-22-2014 02:29 AM

Note to self: don't be messin' with the servo guts.

kyleservicetech 01-22-2014 03:30 AM

Quote:

Originally Posted by hayofstacks (Post 937754)
if the servos move the same direction you can use a regular y-harness. if you have a 7 channel radio you can use different channels for each servo and set up crow if you would like.

if you need to reverse a servo, you need a reversing y-harness or if you want, you can reverse two wires on a servo extension or make your own.

Nope. :D :D :censor:

Our servos have three wires, black is battery negative, red is battery positive, the third is signal (a repeating pulse type signal)

Reverse the red/black, and you've fried the servo electronics. That's the same as connecting your 12 Volt Lead Acid battery backwards in your car. Reverse the signal with red or black, and you could potentially fry the receiver. Or the servo. Or both the receiver and servo. Depending on Mfg of the receiver and servos.

Reversing the servo requires going inside the servo, switching the two wires to the DC motor, AND reversing the two outside wires to the servos internal feedback pot.

More than a few of the servos I've seen, the motor is soldered directly to the servo circuit board, making reversing the motor connections nearly impossible. Worse, I ran across one Futaba servo, where just disconnecting the motor destroyed the motor. That was on a "Coreless" type motor.

There have been reports that some brand servos run "Clockwise" and other brands run "Counterclockwise" on the same servo signal. Perhaps the wattflyer readers can provide some input on which servos do what.

maxflyer 01-22-2014 04:48 AM

My Fun Cub is set up with each aileron servo on it's own channel, The flap servos operating through a wye on one channel, and I also have the ailerons acting as flaperons. Easy to do with my Taranis, but this complexity was problematic when tried on my Hitec Eclipse 7 Pro. I was able to just go with the installed Hitec RX by adding a module to the Taranis, also allowing me to use my extensive collection of other Hitec RXs.

fhhuber 01-22-2014 04:51 AM

Futaba servos operate reversed from JR, this is a legacy of Futaba using - shift and JR using + shift with 72 mhz.

You can order "reversed" servos in almost any brand for an added charge.

You can get digital programmable servos and the programmer and do the reversing (and other electronic modifications) yourself also.

Generally you want matched brand and model servos for any given function. If the right aileron servo is a Futaba 3003 then the left should be a Futaba 3003 also. That doesn't prevent you from then using something else for the rudder or any other function.

hayofstacks 01-22-2014 04:53 AM

that's all news to me. I made a reversing harness and used it a lot on my alpha 450 sport when I was flying it. never burned anything up.

kyleservicetech 01-22-2014 06:09 AM

Quote:

Originally Posted by hayofstacks (Post 937796)
that's all news to me. I made a reversing harness and used it a lot on my alpha 450 sport when I was flying it. never burned anything up.

???
Only reversing harness I've ever seen is where the harness included some electronic circuitry between the receiver servo output and servo cable that electronically reversed the signal.

Don't see any way a servo would be reversed by switching the three servo lead wires leading to the receiver.

Do you recall any drawings, or hookups???

hayofstacks 01-22-2014 06:51 AM

I just pulled it out and looked at it. it wasn't wired differently. just a regular y-harness. ignore me. sorry for the bad info.

cyclops2 01-22-2014 02:55 PM

No problem.

That is what this forum is supposed to do..........Help people who are not absolutly sure about something.


Always post the question then WAIT for at least 2 or 3 same type of answers. Not enough answers ? Send a PM to someone like kyleservice.

We have the knowledge. We like to pass it on.

Keep posting questions.

Rich

kyleservicetech 01-22-2014 04:45 PM

Quote:

Originally Posted by hayofstacks (Post 937802)
I just pulled it out and looked at it. it wasn't wired differently. just a regular y-harness. ignore me. sorry for the bad info.

Naw, no problem.

(I've had my share of postings in wattflyer that had to be "updated" :oops: :oops:)

DavidR8 01-22-2014 09:16 PM

I'm trying to reduce wires
 
Quote:

Originally Posted by maxflyer (Post 937793)
My Fun Cub is set up with each aileron servo on it's own channel, The flap servos operating through a wye on one channel, and I also have the ailerons acting as flaperons. Easy to do with my Taranis, but this complexity was problematic when tried on my Hitec Eclipse 7 Pro. I was able to just go with the installed Hitec RX by adding a module to the Taranis, also allowing me to use my extensive collection of other Hitec RXs.

Same setup for me except that each flap servo is on its own channel and slaved to the master. I think... I have to admit I'm still foggy on master/slave, p-mixes and other black arts of computer radios.

I'd like put the flap servos on a Y-Cable so there is one less wire. I'd also like to have them on channel 6 so I could use the VR dial on my 7C radio to adjust their throw.

cyclops2 01-23-2014 12:48 AM

Some planes are NOT designed by a person who really flys them. :concern:

maxflyer 01-23-2014 05:02 AM

Your description of trying to get stuff to work on whatever channel YOU like, etc. is how I ended up with a Taranis. I really like my Eclipse 7 Pro, but from now on it will be mostly relegated to 3 and 4 CH birds.


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