Aileron leveling

[rc_pilot]

Hi R/C experts,

Before I came to know about MRC, I had bought the UMX carbon cub (and promptly crashed & broke the wing). Now that I've read all the great reviews about beginner planes, I've purchased the Pandora (yet to assemble it though)

But, in the meanwhile I ordered a new wing for the UMX so that I can try this out in a nearby park (since the plane is so small). But, I have an issue with both the ailerons not leveling at all. Before connecting the lipo, I made sure both of them are perfectly level (using the rotary gears), but once I bind with my DX6i radio, they just drop down (the right one more than the left). I've tried doing some trimming, but still doesn't look good. Any idea what could be wrong? I've attached some snaps here:

Pic #1: Both ailerons are aligned before binding


Pic #2: Right aileron drops after bind


Pic #3: Left aileron drops after bind


I've tried moving the rotary gears after binding, but I guess they don't take effect. Would appreciate any help

Thanks much

[Hippie 64]

RE: Aileron leveling

Check to see if you have reversed your Chanel first . Then you need to take the screws out ant pull your servo arms off the servo . 
Plug in your battery reset your trim to center so you have adjustments later . Hold one of the ailerons level as you can get to the wing and put your servo arm back onto servo . If you feel confident it's good  put screw back and repeat for the other side . 
Also looks like you need a make sure your servos are installed opposite of each other . If one is turned one way the other needs to be turned opposite . Ex. If the screw on the servo is pointing in towards the middle so should the other . This will make them work together in opposing directions for proper function


Bryan

[Tootall505]

RE: Aileron leveling

Make sure you have the correct WING TYPE selected on the radio. This might be you problem.

[Lon]

RE: Aileron leveling

This may sound dumb, but, when you adjusted, you had verified with a servo tester that your servos were in their center position before making adjustments on the horns.  I know one time myself, thought the servos were centered and made adjustments, and then when I powered up...oops, servos centered, and had to do adjustments on horns again, then no problem.

[Grossman56]

RE: Aileron leveling

sounds like another Pandora convert!  Assemble.....Fly!...........
Play with the annoying problems when it snows, Assemble!.........Fly!..........

Grossman56

[WintrSol]

RE: Aileron leveling

Before connecting the lipo, I made sure both of them are perfectly level (using the rotary gears), but once I bind with my DX6i radio, they just drop down (the right one more than the left). I've tried doing some trimming, but still doesn't look good. Any idea what could be wrong? I've attached some snaps here:

So, you manually moved the servos to the point that the ailerons were 'level'? Servos do not use the position they start in as center when they are powered, center is set by the position of a potentiometer inside the servo, and is compared to the signal from the receiver, so moving them manually has no effect, they will move to the position commanded by the receiver. The receiver does not issue this command until it is bound to the transmitter; once that happens, then, and only then, are the servos locked to the command position the transmitter is sending to the receiver. After that, you connect the arms to the servos, so that the controls are near center, and make any adjustments to get them 'just right'.

Using a servo tester only gets you close, unless you know the command pulse your radio sends when the controls are centered. For example 1500uS is the standard center, but my Futaba radio sends ~1520uS; since I have measured this, I can get my tester to set the 'correct' center for my radio, then have minimal adjustment after the radio is powered and bound to the transmitter.

[Lon]

RE: Aileron leveling

Before connecting the lipo, I made sure both of them are perfectly level (using the rotary gears), but once I bind with my DX6i radio, they just drop down (the right one more than the left). I've tried doing some trimming, but still doesn't look good. Any idea what could be wrong? I've attached some snaps here:

So, you manually moved the servos to the point that the ailerons were 'level'? Servos do not use the position they start in as center when they are powered, center is set by the position of a potentiometer inside the servo, and is compared to the signal from the receiver, so moving them manually has no effect, they will move to the position commanded by the receiver. The receiver does not issue this command until it is bound to the transmitter; once that happens, then, and only then, are the servos locked to the command position the transmitter is sending to the receiver. After that, you connect the arms to the servos, so that the controls are near center, and make any adjustments to get them 'just right'.

Using a servo tester only gets you close, unless you know the command pulse your radio sends when the controls are centered. For example 1500uS is the standard center, but my Futaba radio sends ~1520uS; since I have measured this, I can get my tester to set the 'correct' center for my radio, then have minimal adjustment after the radio is powered and bound to the transmitter.

[rc_pilot]

RE: Aileron leveling

Thank you all for the prompt & very useful replies. All the servos are supposed to be in 'N' position with no sub-trim whatsoever, as per the manual. After speaking to MRC tech support, I manually adjusted the metal linkages AFTER the plane is powered up. The control rod has a 'U' shaped bend which can be either shrunk/pulled-out as needed. This is exactly what I had to mess with

As WintrSol said, whatever I did before plugging in the battery was pretty much useless since once it's powered up all the control surfaces (the ailerons being very prominent) changed positions. With this change, the ailerons look good. Can't wait to try it out once it stops raining, but not complaining since we desperately need water here in CA :-)

[rc_pilot]

RE: Aileron leveling

Just to update this thread: I took it out for a re-maiden after fixing my wing & it flies pretty well, even with a slight breeze. Thanks again for all the tips

[Hippie 64]

RE: Aileron leveling

Great news !!!! Always good to hear of success .

Bryan