Tail Question

[the-borg]

I'm in the process of setting up a 500 with a 4 blade Align head that will eventually go in to an Apache fuz.
The issue I have is when I apply collective from the hover the tail kicks Right nose left I have tried adjusting the gain on my TX a DX8 but is seems to have no effect what ever. This is my first BeastX so any help will be appreciated.

Regards
Stuart

[GIXERMAN]

You can use tail pre comp setting to compensate for torque

[the-borg]

You can use tail pre comp setting to compensate for torque

Thanks I will give it a go tonight,

Stuart

[askeys_heli_madness]

Have you got a flat throttle curve. I had this issue with my BeastX, could not get tail to hold when applying significant pitch. Issue was cured by having a flat throttle curve. Therefore the tail only has to compensate for torque generated by pitch of blades and not sudden increase in head speed as well.

[the-borg]

Have you got a flat throttle curve. I had this issue with my BeastX, could not get tail to hold when applying significant pitch. Issue was cured by having a flat throttle curve. Therefore the tail only has to compensate for torque generated by pitch of blades and not sudden increase in head speed as well.

At the moment I have 0 25 50 75 100 on the TX.

Stuart

[tomatwalden]

At the moment I have 0 25 50 75 100 on the TX.

Stuart

That looks like a pitch curve - not a throttle curve ?? What have you got for throttle?

[the-borg]

Hi Tom

Both the throttle and Pitch cures are the same 0 25 50 75 100 a stright line from Low to High on the throttle stick

The DX8 has a tail "Tail Curve- For non -Heading Hold Gyro Use Only" This is set as a flat line

[tomatwalden]

I don't know if this is exactly your problem, but that throttle curve certainly isn't one I'd recommend. By having a linear curve rather than flat, all changes in the collective (left stick) will not only change the pitch of the blades, but also constantly change the throttle of the motor. As hinted above, the BeastX will then have a harder time trying to compensate against constantly changing torque from the motor. I would suggest (normal mode) throttle and pitch curves more this :

Pitch : 30, 40, 50, 75,100
Throttle : 0 , 50, 80, 80, 80

With this, once you achieve positive pitch (ie. lift!), your throttle has reach 80, and STAYS at that throttle whilst you're flying around. Height is controlled by collective pitch. For "idle up" flying modes (aka stunt mode) - you should have something like this :

Pitch : 0, 25, 50, 75, 100
Throttle : 80 , 80, 80, 80, 80

[the-borg]

I can give it a try.

My pod and boom has a 3GX FBL in it unit and works ok with both Linear and flat line throttle curves so that why I started with a linear throttle bit i guess the BeastX is a different type unit.
I was recommended the BeatX over a 3GX for a multi blade head in a scale Fuz.

[tomatwalden]

I can give it a try.

My pod and boom has a 3GX FBL in it unit and works ok with both Linear and flat line throttle curves so that why I started with a linear throttle bit i guess the BeastX is a different type unit.
I was recommended the BeatX over a 3GX for a multi blade head in a scale Fuz.

My comment isn't really specific to the BeastX - linear throttle curves (excepting spool up) are kinda weird anyway. Constantly changing throttle isn't really good for any unit - including the 3GX. I doubt it is the root cause of your problem I'm afraid.

[tomatwalden]

How much of a kick? Minor niggle, or proper blow-out ?

[the-borg]

How much of a kick? Minor niggle, or proper blow-out ?

Is not a violent kick but it dose go from tail in to side on.

[Myken]

What tail servo are you using and how far is the ball installed from a center? It should be installed as close to the center as possible while still allowing a full tail slider movement without binding.

If your tail blade grips are stiff and do not have any play in them you can try to increase BeastX Tail HeadingLock Gain - Parameter D and readjust gain in the Tx until you get a fast wobble and then decrease a bit.

That on its own should be pretty good already, if it still kicks when changing collective, then look at Tail Torque precompensation, that should eliminate the rest.

I hope this helps .

Edit: Did you select a correct servo frequency for your tail servo?

[askeys_heli_madness]

How much of a kick? Minor niggle, or proper blow-out ?

I was the one who posted earlier regarding the throttle curve. When I first set the beastx up (new model memory in tx) I did not alter the throttle curve to those stated in 'tomatwalden's' earlier post. This played absolute havoc with the beastx, total tail blow out, 90-120 degree tail kick!

I was altering gyro gain, pre comp torque' and allsorts. I was at my wits end, blaming the beastx, and almost ready to throw it in the bin. When I altered the throttle curves to a flat response ie 0, 50,80, 80, 80 (IU 0), and (80,80,80,80,80) (IU1) the problem went away. As stated earlier much easier for the tail to compensate for torque generated by blade pitch alone, however a rapid increase in headspeed as well and its got no chance.

[the-borg]

What tail servo are you using and how far is the ball installed from a center? It should be installed as close to the center as possible while still allowing a full tail slider movement without binding.

If your tail blade grips are stiff and do not have any play in them you can try to increase BeastX Tail HeadingLock Gain - Parameter D and readjust gain in the Tx until you get a fast wobble and then decrease a bit.

That on its own should be pretty good already, if it still kicks when changing collective, then look at Tail Torque precompensation, that should eliminate the rest.

I hope this helps .

Edit: Did you select a correct servo frequency for your tail servo?

There are HK15158A Digital BB/Coreless Mini Servo
Spec.
Torque: 2.3kg @ 4.8v, 2.8kg @ 6v
Weight: 25g Speed: 0.08 / 60deg @ 4.8v, 0.07 / 60g @ 6v
Voltage: 4.8v~6v
The ball is two holes out from the center and there is no binding on the tail blades.
servo Freq is as per servo instructions.

The Gain pots on the unit are still at the center position I have not touched them.