Hi,

What kind of rudder delay would be suitable for this RJX tail servo please? If it matters it is in a Gaui X4 II.

Thank you!

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rjx tail servo fs-0391thv

Specs:
Operating Voltage: 6.0~8.4V
Torque:
8.4kg/cm (116.7oz/in) @ 6.0V
9.6kg/cm (133.3oz/in) @ 7.4V
10.6kg/cm (147.2oz/in) @ 8.4V
Speed:
0.035sec/60° @ 6.0V
0.032sec/60° @ 7.4V
0.03sec/60° @8.4V
Frequency: 760us/333hz
Gear Type: All metal gear
Plug Type: JR
Dimensions: 36x15x35.5mm
Weight: 50g

I recommend to set it to 0-3.
Also very important is to configure Piro Consistency parameter properly. For your helicopter it may be around 170.

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Spirit System developer

Thank you. I have it at 180 and think that it is flying pretty good. For me, it's prob my best flying model right now.

I am chasing one bad behaviour, can you help?

During upright TicTocs I see a slight aileron movement. It is almost as if the heli does not stay facing me. Could be wind, and I suspect could also be the tail (although if it were the tail I'd expect it to walk left/right rather than look like an aileron movement).

Should I increase cyclic gain to see if this helps? Currently at 60. Running an X5 boom with 473mm main blades (stock mid sized Gaui X4 servos).

You are welcome. RJX servos are performing very well, but unfortunately sometimes such strange issues may occur if you are lucky.
Also make sure that any servo is not overheating.

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Spirit System developer

Great.

So is cyclic gain what I should be adjusting?

I am not sure if this helicopter is same as this what you are asking about in another thread, but if your elevator servo is not working correctly sometimes then it can cause such bad behavior.

It it also important to tune rudder first so it will hold well, because inprecise rudder behavior can cause oscillations even on the cyclic.
But yes, you can adjust Cyclic Gain, this should help you normally.

_________________
Spirit System developer

Hi,

Yes, it is the same heli. I will keep this in mind (tail holding + ele servo) while tuning, and when re-testing 1.2.1. Thanks.

Results from testing:

No short between servo casing and signal. Servo looks fine.

I removed all revo mix and adjusted the rudder delay from 10, to 0.
I then increased tail gain, up to 100% without any adverse affects. I had to get to 1.2x on the tail before I started seeing mild oscillations in piro stops. FFF was fine even so.

So even at about 85% gain the heli is very well locked in, probably more so than it was before even with the revo mix.

I can get a slight twitch on the tail if I hammer the sticks in pitch pumps, but it's holding very well given that kind of full collective punishment. I may try -1 revo to see if I can get that last 3%.

I have got up to 70% cyclic gain with little noticeable difference. I think it's better, it has no ill effects in a mild descent. No wobbles. It doesn't do anything adverse in funnels or FFF. I'm very happy.