Big bobbles......

[smaze17]

Ok guys so I posted this over in the tuning guide thread but thought I should post it in the main thread as well.

I have gone over the tuning guide with a fine toothed comb but I can't seem to get it right.

It's kind of hard to explain but with my 450 Sport when I do a quick descent then pump the collective hard it pulls rather drastically to the left, i.e. hard left cyclic. I guess you could say the cyclic bobbles. I am in transmitter mode with 120% ATV on aileron and elevator and 20% expo on both.

I heard somewhere that the CC governor could possibly be causing this?? I am using a Castle ICE 50 governed to 2700, 2800 & 2900.

I'm not really sure where to begin.

Thanks for the help!

S

[JustPlaneChris]

I doubt the governor would cause a cyclic bobble. Tail yes, cyclic no. What blades are you running? I've read of very similar behavior from a Mini Protos that was totally cured by running FBL-specific blades....

[smaze17]

Originally Posted by JustPlaneChris

I doubt the governor would cause a cyclic bobble. Tail yes, cyclic no. What blades are you running? I've read of very similar behavior from a Mini Protos that was totally cured by running FBL-specific blades....

Hi Chris. I am running the standard Align 325D's - non FBL version. Come to think of it I believe it was a little better when I had FBL blades on there. Might try reducing the cyclic gain a bit too.

Thanks for the response

S

[John Cook]

dammit
I first read your thread title and thought it said "big boobies"
I got excited for a half second there

[smaze17]

Originally Posted by John Cook

dammit
I first read your thread title and thought it said "big boobies"
I got excited for a half second there

LOL

Raised pot 1 up to 0 and the sport is rock solid

S

[Roger Palacio]

Originally Posted by smaze17

LOL

Raised pot 1 up to 0 and the sport is rock solid

S

When you said you raised it to 0 was that + or - ???

Thank you

[Roger Palacio]

I just turn (lower) two clicks to the - side and now my T-rex 250 is flying like a dream.
He is alive !!!!!!!!! LOL

[Inverse]

This isn't bobbles, a bobble is an oscillation on cyclic stops.
You sure your swash is leveled properly?

[urgno]

Originally Posted by John Cook

dammit
I first read your thread title and thought it said "big boobies"
I got excited for a half second there

same here
let's give something to see for the misreaders

[smaze17]

Originally Posted by Roger Palacio

When you said you raised it to 0 was that + or - ???

Thank you

I "raised" pot 1 to zero. It was about three clicks into the negative.

S

[smaze17]

Originally Posted by Inverse

This isn't bobbles, a bobble is an oscillation on cyclic stops.
You sure your swash is leveled properly?

It seemed lime a bobble to me but maybe I didn't describe it correctly.

Good lookin' out on the level swash thing - I will re-check that today

S

[Shawn Behrens]

I am glad you got your boobles worked out, but I would like to mention. You stated that on your setup that you have the radio setup for the control of the flip,roll, and yaw rate. You also mentioned that you have your dual rates set to 120%. I read somewhere on the beastx site that it is not recomended to go beyond 110% (and that is with the channel epa's at 100/100) to achieve a fast flip n roll, the beastx site mentioned that this could produce some strange flight characteristics.

You mentioned your HS was governed to sub 3000 rpm. Raising your HS would allow for a faster flip and roll thereby allowing you to lower your out of recomended range dual rates.

shawn

[smaze17]

Actually I do not use dual rates. My ATV's are 120% for aileron and elevator.

I will give the higher headspeed a try though...thanks for the advice

S

[sutty]

Dual rates or ATVs amount to the same, but either way you should not go beyond 110%. 100% gives full rotation rate, and subject to radio variation, 110% should be enough to make sure the MB recognises it as 100% output from your radio. More than 110% will just lead to the MB hitting its full rotation rate early in your stick travel.

The conclusion being is that if the MB hits 100% rotation rate when your radio hits 100% travel, 110% to be sure, then any more than this will just lead to dead bands at the end of the travel where further movement of the stick will achieve nothing, and where the resolution of your stick movement is reduced.


See quote from Stefan below:

Stefan Hornstein
14. April 2011, 17:30

"Hi,

no expo will not confuse the MB, it only will confuse YOU. Please read this:

http://www.beastx.com/showthread.php...expo-on-beastx


When using the preset characteristics it is recommended not to adjust expo in the tx as this will mix the expo coming from the tx together with the curves in the MB which can lead to a very inaccurate, in extreme constellations even to unpredictable, control. But if you like this you can also do this.

Changing rotation rate by using DR or servo throw adjustment in contrast can be done also in these modes, as this will only compress or stretch the curve.

"Normal" has very much expo and less rotation rate up to "extreme" with nearly none expo and high rate. This different characteristics are test flown by us if you don't like these you can switch to "blue"/"transmitter selected" and make your own expo curve in the tx. Additionaly when "transmitter" is selected 100% stick output corresponds to full rotation rate (differs from tx to tx, so it can also be 110% or more). So by adjusting servo throw or dualrate you can also change the rotation rate."

Cheers

Sutty

[smaze17]

Not sure I follow you??? I am in transmitter mode. Many people go up to 150% to get super fast roll rates. I am not using any of the preset flight modes. Although I did use Pro once and it felt pretty close to the way I fly with approximately 20% expo. At least I felt close to this anyway.

S

[sutty]

My interpretation of the quote from Stefan is that 100% radio value equates to 100% roll rates from the MB. That's it, no point going to 150%, you just hit 100% 2/3 of the way through your stick travel, and any further movement of your stick will achieve nothing further. This means all of your control variation is limited to the first part of your sticks travel, the rest simply becomes a dead band. In this 2/3 section, you have all of your control variation, so you have less stick resolution overall, but perhaps 110% being required to ensure you hit 100% subject to individual radio variations.

Hope this helps.

Cheers

Sutty

[smaze17]

This is news to me and I would venture to say news to everyone who uses the Beastx.

If I increase throws via the transmitter the roll rates are noticeably faster. Everyone I've ever spoken to agrees that when you are in transmitter mode, if you increase your ATV percentage, your roll rates will be faster.

I can attest that this is in fact true.

S

[sutty]

Well I can only go off what Stefan has said, and he is a MB developer. In another quote, which I cannot find right now, he states it even more unequivocally. I set mine to 110%, to be sure I wasn't falling short, and it is very fast. I didn't try more because I was where I wanted to be, but also because of what I read from Stefan. Others are aware of this too, I have read it many times.

Why you can also read reports that going as high as 125% or even 150% might speed it up I can only think that hitting your maximum roll rate early in the stick travel might easily make it feel a lot faster because at say 150% you can go from 0 to 100% radio value by 2/3 of the way across, which would mean you got there quicker, and everything will certainly feel a lot more sensitive, as you have much less resolution, but once you hit that maximum roll rate figure, it will not roll any faster, and according to Stefan that occurs at 100% radio value.

Don't know what else to read into what he has said?

Maybe we should see what others say.

Cheers

Sutty

[smaze17]

Very interesting stuff Sutty

I wish others would chime in. Quite frankly this is the first time I have ever heard that you shouldn't go over 100% travel adjust when using transmitter mode.

S

[JustPlaneChris]

Originally Posted by sutty

My interpretation of the quote from Stefan is that 100% radio value equates to 100% roll rates from the MB. That's it, no point going to 150

That has NOT been my experience. I can see a definite increase in roll/flip rate when increasing the end points beyond 100%.