450 Dominator shake

trainrider06

trainrider06

Active Member
I thought I noticed this the other day, but really noticed it today while burning pack down that I had charged after my fly day Friday, in Idol 1 this baby is shaking!!
You can see the skids jittering about flicking idol 1 on. It has a brand new main shaft, feathering shafts, head bearings, etc... The blade grips though I noticed had a slight up and down play in them...
They are tight pulling them apart, no play there, have the new version head on it too.
Anyone know of a way to kinda localize the vibration area??
Would the TT tail cause this in any way?
 
Smoggie

Smoggie

Well-Known Member
I wouldn't expect the TT tail to cause a shake on the skids. The usual cause of this is running too low headspeed and/or having the cyclic gain set too high. The Trex DFC heads have rigid dampers which only work well at higher RPM.

This assumes the blades are well balanced and the tracking is good...
 
trainrider06

trainrider06

Active Member
I was watching the blades and they appear to be on as far as tracking.
Have an app on phone I can check head speed with, right now my throttle curves are
0/65/65/65/65 I 0
75/75/75/75/75 I 1
85/85/85/85/85 I 2
I'll see about a video...
Oh in Idol 0 it doesn't vibrate, I suppose I should check blade balance also.
 
trainrider06

trainrider06

Active Member
I have gains set around 60 (BeastX) but the tail was blowing out really bad on pitch pumps, and it shook before that too!
 
Smoggie

Smoggie

Well-Known Member
We are talking head gain too high, not tail gain. The fact that the tail blows out also points to head speed being too low. What throttle % are you using?
 
Tony

Tony

Staff member
Yup, as Steve stated, we are talking about cyclic gain, not tail gain.

Does it shake at 85? If so, being combined with 75 shaking means you need to lower your cyclic gain on the face of the gyro.

And yes, 65 is very low. My helicopters HATE flying with that low of head speed. That is like me flying my 600 at 1700 head speed, but I do it lmao. But, I have an Ikon which is the shiznit and everything is solid as a rock, just sayin' lmao.

Lower that cyclic gain and I bet your issue goes away.
 
murankar

murankar

Staff member
Those DFC heads have ranges of head speed that they hate. It sounds like the 75% throttle is one of those spots. On my Gaui (different head style) I can go as low as 2700 and as high as 3700. I have not had it that high but at the 2700-3200 range mine is rock solid. Again I have a traditional fble head with followers and not DFC. My Goby seems to like to be over 2200 for solid stable flight. Make sure you know what head speeds you have and see if they are near what you want. And yes the higher the head speed the lower your gains will be. Head speed acts as a mechanical advantage and fights the FBL controller. With higher mechanical advantage the lower your gains are going to be.
 
trainrider06

trainrider06

Active Member
Tony said:
Yup, as Steve stated, we are talking about cyclic gain, not tail gain.

Does it shake at 85? If so, being combined with 75 shaking means you need to lower your cyclic gain on the face of the gyro.

And yes, 65 is very low. My helicopters HATE flying with that low of head speed. That is like me flying my 600 at 1700 head speed, but I do it lmao. But, I have an Ikon which is the shiznit and everything is solid as a rock, just sayin' lmao.

Lower that cyclic gain and I bet your issue goes away.
Click to expand...
Lower cyclic gain in the BeastX?? Where do I do that?
 
Tony

Tony

Staff member
On one of the pots on teh face of it. Refer to the manual to figure out what one it is. I can't remember.
 
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