Trex 450 Tail Rotor Tuning

That looks like perfectly reasonable tail settings for a smaller size heli. The tail response depends on a lot of things beside servo speed too. Headspeed (and associated tail rotor speed) can affect it. And 3D pilots are always trying different blades to find the “perfect” combination. And on some you can change the gears. On my Synergy 626, for instance, I reduced the tail rotor speed by swapping out the 4.5:1 gears for 4:1 in the tail transmission. Then replaced the stock 96 blades with 106’s. That simple change reduced the required power in hover by ~45 watts and actually improved the tail response.

So. Long story short: Looks like the real culprit of all my compass trouble was actually the pixhawk unit I was using.
It would not recognize any of my new GPS’ (A Here GPS and a mRo unit), so mounted a different pixhawk and after a lot of faffing. (The Here GPS has some quirks too), I finally got it working pretty much flawlessly today.

GPS was solid. Compass was solid. Tune is decent. Gimbal and FPV Pan & Tilt is working. (And more or less synced).
Needs some wiring clean-up, but I have yet to decide which connectors to use for payloads.

Need to get it out to larger area so I can stretch it’s legs…even 5 m/s looked too fast for that area!.

This post is very helpful. However we have a step by step mechanism to tune the roll and pitch which is well documented here. I think it would be great if we can come up with a similar mechanism for yaw as well. The guide lines mentioned here are fine but every heli is different and there a variety of factors due to which we cannot use prefixed values for yaw tune. I will do some experiment and see if we can have yaw time mechanism which would work on a variety of platforms.

I would recommend using the same procedure that is currently used to tune pitch and roll and see if it is any better or worse. You may want to keep a little P gain in there during the initial steps to set VFF. If you have some P gain then you are looking at the point when the P contribution to the PID reverses to reduce the amount of input. That then tells you that you have enough VFF. Then tune the P and D gains as is discussed for pitch and roll. I have tried it but I’m not as critical of my tail as most so I would like to see what others think.