Servo travel and channel resolution ?

[Dawiev]

Hi, I'm trying to get the tail sorted on a Blade 550x. I've rebuilt the mechanics a few times, reset and redone the setup with no luck.

Travel is set to be 100% both left and right in the Transmitter screen of the IKON software. (This requires the servo travel in the DX9 rudder channel to be 128 both ways). The Advanced menu throw for servo 4 is 605 / 580.

When I move the TX rudder channel left or right it reaches max mechanical travel after 40% movement and on the Transmitter screen it shows only 15 / 17%.

The result is that all the rudder travel is used in the first 40% of the stick movement in a given direction.

What have I done wrong please ?

[mamartin]

I guess I'm not understanding your question. Maybe a little more info could help.
If your heli is at rest on ground or work bench without motor running and your in heading hold mode and you only give a minor amount of rudder input, like say 5% stick input Your Brain will be expecting to see a change in heading due to the rudder input command and if its sitting stationary it will then begin to feed more and more tail pitch into the heli in an attempt to achieve the command given and will keep adding more input until it reaches maximum throw until you let of the rudder stick.

Is this kind of what your seeing thats confusing you?
If not please give more infor so your question can be better answered.
Thanks

[Manyc]

Ahh.. I think you have to much mechanical gain in your rudder.. Try moving the ball on the tail arm in a bit...

If I'm understanding correctly..

[Dawiev]

Hi, thanks for the replies.

So I just figured out the difference between head hold and rate mode ? (the name "rate mode" says it all ! )

The problem I'm trying to fix is violent shakes, when turning around at the end of FFF. In all other conditions tail is good. I'll try and apply more patience to set the tail up from the beginning, to understand if it is overshooting, or over-correcting.

[HeliWobbles]

I think what Dawiev is wanting to know is what range of settings in the tail servo travel that are ideal to indicate correct mechanical gain.

Most tails achieve about 45 degrees deflection. If I end up with a + & - throw of 150 I am guessing my mechanical gain is too high. If the throw (in advanced/common/servos/servo 4) is at over 1000, I would think that my ball is too close to the centre of the servo.

This as all guesswork but can one of the developers please post the ideal range? Better still, many other parameters have a blue boxed mouse-over tool-tip with defaults, can the ideal range be displayed the same way?
Ted.

[mamartin]

Originally Posted by HeliWobbles

I think what Dawiev is wanting to know is what range of settings in the tail servo travel that are ideal to indicate correct mechanical gain.

Most tails achieve about 45 degrees deflection. If I end up with a + & - throw of 150 I am guessing my mechanical gain is too high. If the throw (in advanced/common/servos/servo 4) is at over 1000, I would think that my ball is too close to the centre of the servo.

This as all guesswork but can one of the developers please post the ideal range? Better still, many other parameters have a blue boxed mouse-over tool-tip with defaults, can the ideal range be displayed the same way?
Ted.

There's a way and i will try to explain this

[BrainDev]

Originally Posted by Dawiev

..........The problem I'm trying to fix is violent shakes, when turning around at the end of FFF. In all other conditions tail is good. I'll try and apply more patience to set the tail up from the beginning, to understand if it is overshooting, or over-correcting.

As with any other tail gyro in world, if you have shakes during a FFF curve, your gain is too high for your model/tail servo/tail blade.
You need to lower the main tail gain in your transmitter.
If you must go too low with tail gain in the transmitter, short the tail servo horn because your tail mechanical gain is too high.

[Dawiev]

Hi, thanks for the reply !

During the FFF part, stationary pirouettes etc the tail is good. No wag, no humm etc. It is only when I get to the end of the FFF run to come back ( pull elevator back, reduce pitch and turn 180 left or right way round ) that it happens, and violently at that.

Come to think of it again, it doesn't happen if I pull up, hover for a few secs and then turn back = stationary piro.

[mamartin]

Originally Posted by Dawiev

Hi, thanks for the reply !

During the FFF part, stationary pirouettes etc the tail is good. No wag, no humm etc. It is only when I get to the end of the FFF run to come back ( pull elevator back, reduce pitch and turn 180 left or right way round ) that it happens, and violently at that.

Come to think of it again, it doesn't happen if I pull up, hover for a few secs and then turn back = stationary piro.

Sorry I must've overlooked your second post.
What BrainDev is saying is what I would also recomend.
Are you comfortable flying as fast as possible sideways?
See what results you get from this
Tail sliding changes in direction like you are doing are menuvers that I use as well to help begin to tune my helis tails in as well.

Here is my prefered method.

First after initial setup try to hover the heli at a safe height and flip tail gyro into Rate mode.
Watch and adjust the tail pushrod so that it will hover without any taildrift left or right.

Once this is done reset your endpoints to max travel because I'm sure by now they will have changed.
Then begin the heading hold dialing in process as you were before.
I imagine that if you noticed the tail chattering one way and not the other the first time before the rate mode setup than this time will be much more smoother and will be smooth both ways at the same time.

[Dawiev]

Thanks for all the inputs !

It will be a few days before I can test. I'll be sure to hatch a methodical plan and not to bypass anything (starting with rate mode).