Can't figure out tail wag/vibration

[jshultz]

Align pro dfc, microbeast fbl,

I've got a vibration/wag I can't sort out. I've tried different combos of gyro settings, head speeds, if I go higher headspeed it actually gets worse, tried the tail blades looser and tighter, same with the mains. Blades are balanced. I took it up in rate mode and the gyros not fighting it, because it's basically hands off hover, may have to correct yaw once every 10 seconds. But I did notice in rate that it still had just a tiny little vibration, and I guess the gyro is amplifying it? I'm sure it's something stupid I'm overlooking.

[jshultz]

Took the tail rotor assembly off and took the TT out to make sure the bearing wasn't dead center, it's about 1" or so to one end, decided to spool it up just to check stuff, no vibes at all with the tt out, put the tt back in and put the tail assembly back on had just a teeny tiny bit, put the tail blades on and it vibrates some, a high frequency buzzy vibration. But not what I'm seeing in the tail when I'm flying it.

[jshultz]

I think I'm going to get another tt bearing set coming and try the 2 bearing setup, that may be the fix.

[PilotPin]

Did you lock the inner bearing race to the tt?

[jshultz]

It was glued to the tt, but the bearing felt a little notchy. I replaced it with a new bearing and also added another. The vibe is better but it's still there. I wonder if the main bearings could be siezed a little from sitting up also, causing it to resonate to the tail.

[Sean_M]

I just had similar issues on my new 500 DFC. I am not sure what actually fixed it but I did 2 things:

1) turned off governor mode on the ESC
2) moved the ball on the tail servo to the inner hole

after that the tail was solid.

- Sean

[ragge1]

maybe the tail servo is bad , I too had a tail wag on a new heli so did some modification to fit a full size tail servo ( the only one I had on hand ) and teh wag was gone

[jshultz]

What's a good tail servo that won't break the bank? I'm about tapped out on this build, but I'll throw a little more at it to make it 100%

[jshultz]

It has the futaba s9257 servo now.

[Kiwi_Craig]

try balancing the entire tail assembly; hub, grips and blades as a unit ?

[yakky]

Tail buzz is the worst for FBLs. Good tape can help a lot, where is the microbeast mounted and what tape? Futaba gryo tape is the gold standard.

[jshultz]

I'm using the clear 3m tape. Im using it on my blade 230 and 360 with good results. Mounted in the top shelf on the rear of the frame.


Update. I was playing with it last night adjusting settings and wasn't paying attention and it went into low voltage. Soon as the head speed dropped it became stable as a rock. No wag at all. Too much head speed? Or not enough/too much gyro gain?

[tonys-heli]

You mean you discharged the battery really low?

[yakky]

Originally Posted by jshultz

I'm using the clear 3m tape. Im using it on my blade 230 and 360 with good results. Mounted in the top shelf on the rear of the frame.


Update. I was playing with it last night adjusting settings and wasn't paying attention and it went into low voltage. Soon as the head speed dropped it became stable as a rock. No wag at all. Too much head speed? Or not enough/too much gyro gain?

Sometimes a heli will have resonance in the tail at particular speed. I’d triple check those tail bearings.

And while the clear 3m tape might be fine on your other helis a better (softer) tape usually reduces vibes to the FBL.

[jshultz]

Originally Posted by tonys-heli

You mean you discharged the battery really low?

Not on purpose. I was caught up in changing settings, lift off, land change settings. But as soon as it hit the lower speed I put it down.

[jshultz]

It was the governor in the esc. Turned it off. Wag b gone. Solid as a rock now.

[crasher47]

Align DS 525M's work well on two Trex 500's I have. FBL is Ikon 1. No problems.

[Kiwi_Craig]

I was chasing tail wag on my two, ditched the stock align servos for a faster 600 sized savox tail servo = sorted. spent countless hours rebuilding tails reducing clearances and endless fine tuning on the FBL - as soon as the bigger faster servos went in = rock solid.

[Abenn]

Originally Posted by Kiwi_Craig

I was chasing tail wag on my two, ditched the stock align servos for a faster 600 sized savox tail servo = sorted. spent countless hours rebuilding tails reducing clearances and endless fine tuning on the FBL - as soon as the bigger faster servos went in = rock solid.

If it's a boom-mounted servo the extra weight might have acted as a physical damper.

[jshultz]

I swapped the align 75a esc I had for a hobbywing 120, the tail jitter is back. It was caused by the governor in the align, but this one I can't turn the gov off. If I do I lose the slow start up. Any ideas on how to fix this before I just put the align one back in? I wanted the hw because of the slower startup and I can use 6s packs with slower head speed if I use a 4s to calibrate the governor.