FBL expectations on a sub 250 scale.

[SkyKraken]

I have mounted a zxy-s on a Blade 130x, and for weeks I've been flying and tweaking and flying and tweaking, but I just can't seem to achieve what I have with the oem 3in1.

I have another 130x with the exact same setup, (frame, servos, blades, grips, tail, etc) yet in it I am using the stock Blade 130x 3in1 controller. Basically, the Blade 3in1 is rock solid, and the Tarot is all over the place.

With the zyx-s, its either loose or shakes, shouldn't there be a large window between these two conditions?

Are my expectations to high for the zyxs fbl, or should I be able to get the zyx-s as solid as the 3in1?
There isn't a size issue, as the zxys was never designed for small scale?

Tarot is 4.02 firmware. Servos Hitec 5035s,

What I mean by "all over the place", is in a hover, the heli has no interest in sitting still, i don't expect "hands off" hovering, but I expect something close, because I can achieve that with the OEM. (I can fly the zxy still, but I don't dare try and scratch anything hovering indoors).

I have a zero'd swash, perfect tracking. (I've done all the mechanical to hover ocd)
Could I have mounted the ZYX-S with too much or too little foam?

And when I get shakes, I can't tell if its pitch or roll. Its like a nano bob, but turning down the I gain doesn't seem like the direction I want to be going if I'm trying to get it stable in the hover.

For weeks I've slid over the PID setting, but I don't seem to be able to get it.

[Dr. M]

Interesting idea. Theoretically it should work. Perhaps your cyclic servo arms are too long.

[Daddy]

CG still good? May attribute to looseness (drift). What gain numbers?

[SkyKraken]

Originally Posted by Dr. M

Interesting idea. Theoretically it should work. Perhaps your cyclic servo arms are too long.

I read, a few weeks back, a thread discussing the location of the cyclic rods, and the distance from center, using that information, I determined I should get as close as I could because of the scale I was using.
I moved from the middle hole to the inner most hole.
7.5mm from center, where the 3in1 heli is still in the middle location about 9.5mm.

What are visible signs for too long of arms?
There is room, I could make my own holes and move in another 2mm.

Originally Posted by Daddy

CG still good? May attribute to looseness (drift). What gain numbers?

CG huh. I'll have to revisit that. when I started this and was laying out the components I was concerned about CG, but I haven't really considered it since.

Am I correct in dangling the heli by the main grips and trying for dead flat skids?
It does pirouette very flat. But it could be the comp.

Thanks for fresh perspectives.

If I used too much (2 layers) of mounting foam, what would that effect?
I ask about foam, because the 3in1 doesn't use any, it slides into the lower frame.

[Dr. M]

If you get wag with cyclic gain in the 20's, it's an indication you have too much mechanical gain: ie servo arms too long or swash ratios outside the norm for FBL.

[SkyKraken]

Originally Posted by Dr. M

... or swash ratios outside the norm for FBL.

What is a swash ratio?
I think you are suggesting that its possible that the swash is smaller then the FBL is programmed to handle, and the rate of change is outside that scope of fbls programming.

Dr. M and Daddy, I thank you both.. I now have two avenues to travel.

And from another zyx-s model, a v120d02s, I've been having success with, I think you have put me back on the right track.

Thank you Sirs!

[Dr. M]

Originally Posted by SkyKraken

What is a swash ratio?

It's the ratio of the diameter of the outer swash balls to the diameter of the inner swash balls.

All of the lever arms involved in cyclic control play a role in the total mechanical gain of the system. Starting with the servo arms, outer swash radius, inner swash radius, and finally the length of the blade grip linkage arms.