My Heli vibrates !! - advice needed please :)

[chisnsid]

Hi gang,

so, each time my heli spools up it tries to shake itself to bits, then smooths out once the head speed is up. In the air though, you can still notice the vibration as the exhaust deflector tube is shaking all over the place.

On inspection I found that one of the blades has a slight clunck (well not as much as a clunck but a noticable notch) if I hold the blade grip and move it up and down...

So in the workshop this evening I've stripped it all out and found that the thrust bearing was the wrong way round... the larger diameter was facing towards the blade, not the main hub. So I've changed it round, and replaced the shaft (?) between the two grips for a new one, just in case, but the cluncky bit is still there, but less so. Is my thrust bearing k/o'd after all that vibe then??

Anything else that could cause it?

Mikey

[Edders]

I would check for a bent feathering spindle to due to the vibration and elongated blade grip holes

Edders

[chisnsid]

I would check for a bent feathering spindle to due to the vibration and elongated blade grip holes

Edders

Hi,

yep, that's the shaft I replaced with a new one as when I rolled the old one on a flat surface there was a slight knocking sound as it rolled, as opposed to the new one which rolled smoothly on the same board.

Have to say tho, I couldn't see where it was out, but I replaced it anyhoo..

Mikey

[gazza]

Even an ever so slightly out feathering shaft can cause hell

Thrust bearings should be okay if they feel okay when you rotate the grips mate.

[Butuz]

Hoping not to sound stupid here - but you have statically and dynamically balanced your blades?

If you have, feel free to laugh and point and i''l just goo away

Butuz

[chisnsid]

Hoping not to sound stupid here - but you have statically and dynamically balanced your blades?

If you have, feel free to laugh and point and i''l just goo away

Butuz

they were v-blades, but have replaced them now too (only last night) with NHP razor pro's - i think they are balanced already.

Mikey

[Smoothound]

Always worth checking the balance on blades however good they generally are as you can always get a rogue set made or packed on a friday afternoon

[chisnsid]

well, I'm gonna try to fly tomorrow night or on friday, a test flight, to see if the blades are tracking right, I guess I'll see how much seh wobbles then...

gulp....

wish me luck

First repair job I've done on my heli - gotta say I'm a little concerned about flying her... but I will.

Mikey - legless...

[Jamez]

Have you checked the radial bearing's as well, if they have play in them, that will make you blade notch about when waggled.

[chisnsid]

Have you checked the radial bearing's as well, if they have play in them, that will make you blade notch about when waggled.

nope, but I will do now... cheers

Mikey