got a slight yaw...

[glowingturnip]

Last couple of flights, I noticed that I was getting a slight slow yaw in the same direction (anti-clockwise) when hovering with hands off the right hand stick.

I checked the receiver test screen and was properly getting zeros when stick is centred and the correct travels in either direction, so the transmitter sub-trims are set correctly. I was able to correct the yaw drift with the trims while in flight and fly as normal, but it's a bit annoying. It's a kk2.1.5 controller with stevies 1.19 firmware.

Just wonder if anyone knows straight away what might cause this, maybe the gyro not calibrating correctly ?

I need to do some more experimenting...

 

[HDtallrider]

To eliminate a mechanical cause, like slight differences in manufacturing runs, you could swap out the props to better ones if you are using cheap plastic props. If your props are the good stuff try swapping the left front motor and the right front motor being sure to plug them in for correct rotation. If it then yaws clockwise you have 1 motor operating better than the other. If it still yaws CCW then repeat the same swap on the rear. If it still yaws CCW after swapping the rear motors then you can start looking into the electronics. It could be the controller like you suggested or maybe the Tx or Rx. There are others in the forum better at that kind of problem than me.
One thing about your build that stands out to me is the Emax ESC's. Everything else is of pretty good quality except those. I often read about when a cheap ESC causes a problem it is usually the one with the active BEC. I am guessing it's because the BEC circuit isn't isolated well. I don't know that for a fact and I don't know if that is your problem either. There must be a way to test if they are all operating properly but that's beyond my knowledge. Hope it's something simple and you're flying happy again.

 

[glowingturnip]

cheers mate,

CF props, and I've not crashed it or bumped it or anything since the last good flights, so not those I think.

Will try swapping the motors over, that's a good idea. Will try swapping the ESC's too I guess, that'd identify if it's a problem with #1 which is powering the board. Don't think it can be the rxtx otherwise I wouldn't get 0 on the receiver test.


Actually... I did have the props off recently while testing something, they could possibly have gone back on opposite corners I guess - shouldn't change anything, but worth checking...

 

[HDtallrider]

Good luck. Little stuff like that can just frustrate the crap out of you all out of proportion to how minor it is. Cheers back at ya!!