Align 3G Tail Gyro prob

[J3DI]

The maiden of my new 700LE 3G didn't last too long today although the only damage was a set of tail blades and the tail fin.

I do have the rudder and gyro sense correct, i have checked and double checked that!

Problem:- With gyro in rate mode (red led lit), any tail input coming up into a hover creates a wild 180 to 270 degree piro and doesn't matter what I do with the dualrates or expo, it is still the same. The heli was in the air (just) as I can imagine this happening when light on its skids with the tail on the grass...

Setup was:
Rudder ATV +/- 100
Dualrates 63% Expo +20%
Spektrum SE/7600

Everything else stock 700LE

[callum]

Do you have the correct tail pitch in rate mode? You need about 6 or 7 degrees offset to the left. (iirc)

I always setup the tail mechanically so that the helicopter hovers fine in Rate Mode, with 6 or 7 Degrees offset, then flip into HH mode and forget about it pretty much.

[Geek]

I do have the rudder and gyro sense correct, i have checked and double checked that!

Problem:- With gyro in rate mode (red led lit), any tail input coming up into a hover creates a wild 180 to 270 degree piro and doesn't matter what I do with the dualrates or expo, it is still the same. The heli was in the air (just) as I can imagine this happening when light on its skids with the tail on the grass...

Setup was:
Rudder ATV +/- 100
Dualrates 63% Expo +20%
Spektrum SE/7600

Everything else stock 700LE

which switch are you switching with?
ie gear ect whats that set to on atv?

[J3DI]

Using the gear sw set at +/-75 (+75 is rate mode).
I have the rudder slider centred when in rate mode, the idea was to setup up the correct mechanical centre with the first couple of hovers.

[Geek]

there is the problem then

[callum]

Hmmmm

[J3DI]

Go on tell me please!

[callum]

Go on tell me please!

You need some pitch setup on the tail blades before taking off

Else it will piro round,

[Geek]

well in rate mode it needs the pitch to stay straight
then the gain is the amount it holds but with no pitch no hold

[J3DI]

OK Thanks! I'll do that then!
You know I've been flying over 5 years and never encountered this before! Maybe with the V-bar it compensated because it was always in HH mode.
I thought that i'd be able to trim it on the rudder stick initially until i'd worked out which way to adjust the push rod!

It's been a while since i flew the likes of the SL720 too

Naughty Logo 500 for teaching me bad habbits!

[callum]

OK Thanks! I'll do that then!
You know I've been flying over 5 years and never encountered this before! Maybe with the V-bar it compensated because it was always in HH mode.
I thought that i'd be able to trim it on the rudder stick initially until i'd worked out which way to adjust the push rod!

Yes, In HH mode you can set the tail blade pitch to be centered (0 pitch).


If i remember correctly, With the raptor you align the pitch fork to be 90 degrees to the boom and that would give you the correct amount,



**Takes a look at his Trex 600 Tail**

If you align the pitch fork to be 90 degrees to the boom (¬) That looks about the right amount of pitch needed in rate mode,. See Pics ive took below:

[J3DI]

On 105mm tails, when you align the tailblades tip to tip, is 10mm gap sufficient for the required offset?

[callum]

On 105mm tails, when you align the tailblades tip to tip, is 10mm gap sufficient for the required offset?

Should be the same for 95mm

Align the pitch fork the same as the pictures above, adjust your end points so no binding occurs and go fly it may piro very slowly, if so bit more adjustment via the linkage and should be all set.



Now, you can skip this and align the pitch fork to be center and then just flip in HH and all will be well, but i dont like to do this, because i find it lazy and not the proper way to set up a tail.

Doing it the proper way also helps take some stress off the servo, also less work load for the gyro and servo, and you maintain servo travel points that would otherwise be taken up by the gyro because it would have to compensate for the torque.

[J3DI]

I always found the Sl720 performed better when you'd set it up in rate mode first.
OK, small adjustment then and i'll be back - thanks.

[callum]

I always found the Sl720 performed better when you'd set it up in rate mode first.
OK, small adjustment then and i'll be back - thanks.

Let us know how it goes