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Cabunag60
11-03-2014, 07:49 AM
DX8 on a FMS P40 Warhawk, when i use the flaps one goes up the other goes done, i have 2 servos for the flaps using a y lead on a 6 channel orange receiver, the ailerons are on a y lead as well, if you set the wing for a 2ailerons and 2 flap servo the landing gear wont work, even setting it for one servo for both ailerons and flap, the flaps move like ailerons, one up one down.

If someone with this model who uses a DX8 could send on his settings that would fix the problem, thanks for reading this.

Panther
11-03-2014, 08:18 AM
You either have to turn one flap servo over or put a signal reverser on one side.

hillbille
11-03-2014, 08:25 AM
Normally you can not use a "y" lead on flaps. You need to be able to match the servos for travel and speed and that usually is not able to be done using a "Y".

If you MUST use a "Y" then one of the servos must be reversed as they both will travel in the same direction. They are wired that way. Since you have one on the LEFT side and one on the RIGHT side - they are moving exactly the same - electrically - but opposite due to placement on opposite wings.

The answer is easy - but not simple. REVERSE one of the servos. Either mechanically match it to the opposite servo - or - place a servo reversing cable between one of the servos and the "Y" cable.

In order for both to function in unison MECHANICALLY - they must both be oriented exactly the same - irregardless of their placement in the wings. Both servos must look exactly the same - not a mirror image of each other - but exactly the same. This means that one side - one wing's flap will have it's control placed slightly off from the other. They will NOT be symmetrical! That is just how it is. If it is not a "scale" plane then it really doesn't matter - function matters.

The reverser cable would be more fore a scale plane or a situation where the servo pockets are already set and the geometry can not easily be altered. Then use a servo reversing cable between one of the servos and the "Y" lead. Means extra wire and two more connections to hide, but it is a fairly easy fix to apply.

Hope that helps.

Hillbille

fhhuber
11-03-2014, 09:06 AM
Dual aileron servos, both arms (or tops of the servos if on their sides) point at their own wingtip or both point way from their own wingtip (Right-left wings mirror image each other)

Flaps you point both servos at the same wingtip.

There are a few foam ARF models that you can add flaps to that have the molded positions for the flap servos and arms wrong.... One example is the Dynam 1200 mm P-51 (http://www.nitroplanes.com/60a-dy8939-p51-arf.html). I had to dig out the servo mounting location a bit and relocate the control horn for one flap servo to use a Y instead of mixing 2 channels.
If you look at the pictures you can see that the flaps are nearly ready for operation. Look close at the servo locations (small foam plugs pop out easily) and you will see they are mirror image just like the aileron locations.... This is wrong.

I expect your Airfield model has the same issue where the foam molding guided you to put a servo and control horn in wrong for using a Y for flaps.

AndyKunz
11-06-2014, 08:41 PM
DX8 on a FMS P40 Warhawk, when i use the flaps one goes up the other goes done, i have 2 servos for the flaps using a y lead on a 6 channel orange receiver, the ailerons are on a y lead as well, if you set the wing for a 2ailerons and 2 flap servo the landing gear wont work, even setting it for one servo for both ailerons and flap, the flaps move like ailerons, one up one down.

If someone with this model who uses a DX8 could send on his settings that would fix the problem, thanks for reading this.

Change wing type to 1 aileron/2 flap. That will allow you to reverse the one flap.

Now go to Switch Assign screen. Set all switches to INH, then set Gear to an unused AUX channel.

Done.

Andy

kyleservicetech
11-06-2014, 10:35 PM
Change wing type to 1 aileron/2 flap. That will allow you to reverse the one flap.

Now go to Switch Assign screen. Set all switches to INH, then set Gear to an unused AUX channel.

Done.

Andy

As for me, I've programmed my DX8 transmitter for two aileron servos, and two flap servos, per the setup guide in the DX8 LCD display. That makes it really simple to adjust the neutral point, and the amount of throw on all four channels.

My models don't have retractable gears, so the gear switch has been assigned the function of throttle kill.

One of my club members had a giant scale 125 inch wing span model with a twin 150 cc gasser up front. After about a dozen flights, he flipped the gear switch immediately after taking off, straight up. Yup, forgot he'd just reprogrammed the gear switch for throttle kill. That $5000+ model went straight in.

solentlife
11-07-2014, 07:33 PM
Change wing type to 1 aileron/2 flap. That will allow you to reverse the one flap.

Now go to Switch Assign screen. Set all switches to INH, then set Gear to an unused AUX channel.

Done.

Andy

Hi Andy .. HOW ? He has flaps on a Y lead and Ailerons on a Y lead ... so reversing will reverse BOTH on any Y lead ...

He needs to split the servos to separate channels ... but I note he's using a 6ch Rx ....

Nigel

AndyKunz
11-07-2014, 08:10 PM
Yes, he does.

He keeps the ailerons on a Y lead and the flaps go straight to rx. GEAR will be left flap, AUX1 will be Right Flap. He leaves the gear down and locked.

Andy