causes of vibration? - HeliFreak
Fun, Learning, Friendship and Mutual Respect START  HERE

Go Back   HeliFreak > R/C Helicopter Support > Century

Century Century Helicopters Support

LinkBack Thread Tools Display Modes
Old 09-11-2010, 05:21 PM   #1 (permalink)
Registered Users
Posts: 84

Join Date: Apr 2010
Location: New Jersey, USA
Default causes of vibration?

I have a hawk sport that I just put a brand new os 37 in today and flew for the first time. It fired right up but I see the heli has a lot of vibration. Is there a checklist I can run through to check the causes? any suggestions on where to start?
f1n3sse is offline        Reply With Quote
Sponsored Links
Old 09-12-2010, 03:07 PM   #2 (permalink)
Registered Users
Posts: 137
My HF Map location
Join Date: Oct 2005
Location: Blackshear Ga

this is just some of them ....


There are only a few systems that can cause a "low speed" shake. (5 - 30Hz) Low speed shakes are the most scarey kind because the thing looks like it might explode or resembles a paint shaker.

Nonbalanced rotorblades
Nontracked rotorblades
Blade grips that are not exactly spaced from the head the same, or have slop in them alowing the blade grips to shift laterally more than .5mm.
A flybar who's paddles are not exactly the same distance out from the center when the paddles are screwed in the same number of turns.
A bent flybar or spindle.
A bent main shaft. Unfortunately the only way to tell if it's bent is to remove it and roll it on glass.
A damaged head.
Excesive slop in the mixing arms possibly.
A set of blades that don't have matched CGs (debatable) Matching the CG is different than just balancing.
Warn out rubber dampeners.
Training gear can amplify a otherwise harmles imbalance into a scarey violent shake. You can usually cure this by running a different head speed and or changing the length of the training gear and how securely or loosely they're fastened to the landing struts.

There are also only a limited number of things that can cause a "high freq shake." (100-300 Hz) High frequency vibrations are most evident by a hum sound comming from the canopy, blurred stabelizer fins, and or foamy fuel in the main tank.

Engine vibrations or bent crank shaft.
Damaged or unbalanced clutch or clutch bell.
Cooling fan not balanced.
Bent start shaft.
Resonating tail drive shaft.
Tail blades unbalanced or not tracking.
Tail mast or hub bent.
Damaged pinions or gears.
redneckteddy103 is offline        Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Copyright © VerticalScope Inc. All rights reserved.

SEO by vBSEO 3.6.1