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deepak
03-07-2011, 11:11 PM
Folks
Have any of you experienced a wobble, much like a hula dancer, on your machine.
Cant figure out what it is. advice appreciated
Thanks
D

kanglou
03-07-2011, 11:16 PM
Check all 3 mainshaft bearings if they goes smooth?nothing in the head that is loose?

deepak
03-07-2011, 11:17 PM
Not that I can tell.
Everything seems smooth. Head tight on shaft .
Any other ideas
D

kanglou
03-07-2011, 11:30 PM
Do you run mikado vbar on your machine?

kanglou
03-07-2011, 11:33 PM
well deepak i saw that you run vbar in the another thread.So how does the spektrum analyzer look like if you have run it?Maby you can lockate where the vibes are?

Maby you should check the TT?So the bearings gooes smooth and the TT is straigt?

deepak
03-07-2011, 11:49 PM
Hi
Will do the vibration analyzer tomorrow and post my findings
Thanks
d

Daniel Jetschin
03-08-2011, 01:56 AM
Hi

Whats your Rpm?

Cletus
03-08-2011, 08:40 AM
From your description of a "Hula Dancer" it suggests a slow, orbital, oscillation. Assuming normal head-speeds, anything in the head would result in a vibration associated with the head-speed and not the "Hula" thing. My thinking is the "Hula" may be an oscillation setup by the Vbar system as it tries to correct the aircraft's attitude. Look at the setup carefully, inspect the spec analyzer and what about auto trimming?

deepak
03-08-2011, 08:59 AM
Morning.
Rotor rpm set to , 1800.1900.2000
does the hula at all 3 settings
D

deepak
03-08-2011, 09:01 AM
Cletus
The auto trim was done prior to changing the head.
I did try to adjust the gains on the gyro to no effect. Have not had the chance to do the spectrum thing yet.
Hopefully today.
Thanks
d

Cletus
03-10-2011, 03:51 PM
Lower is sweeter :lol:
http://i112.photobucket.com/albums/n197/cberkeley/LowBoy2.jpg

Laurens
03-11-2011, 12:01 PM
Are those QuickUK servo horns?

deepak
03-11-2011, 12:20 PM
Yes Laurens,
They are the 9.5mm ones.
Working out nicely
regards
d

united737pilot
03-11-2011, 05:06 PM
Cletus: did you cut down your avant head and use the holes where the flybar carrier was?

Cletus
03-11-2011, 05:38 PM
Cletus: did you cut down your avant head and use the holes where the flybar carrier was?
No, that’s a Custom Short-block I machined from billet for Deepak, to solve his "wobble" issues and gain him some increased cyclic agility.

united737pilot
03-11-2011, 05:58 PM
Wow. Very Nice!!!
Also, what blade grip arms are those?

deepak
03-12-2011, 10:03 PM
Hehe
Wobble and vibration gone!! Finally a vibe free heli.
Main shaft was not true and bearings were shot?
Finally. She's sweet.

Cletus
03-13-2011, 07:06 AM
COOL! ....I've been a fan of SKF bearings for a long time! Use them almost exclusively in all the machinery at my factories.

Laurens
03-13-2011, 07:10 AM
Have you crashed the aurora before? Or where they bad from the beginning?

deepak
03-13-2011, 10:20 AM
Remember Laurens
This is the second main shaft which was not true. I believe the shafts and vibration combo helped destroy them.
I had no crashes but I did have the heli roll left before take off in the earlies twice. Cost me a spindle, main shaft and blades both times. After using zeal tape on the vbar sensor I got it to settle down and work like it should.
The short block is awesome. Flip and roll much tighter.
Thanks
regards
D

fsusmithc2
03-21-2011, 02:15 PM
The blade grip arms in that pic look an awful lot like the ones from the RigidCore head. Interesting. ;)