Fin Vibration Solved

[Redfire SVT]

I finally tracked down the source of my horizontal fin shake. I already inspected and/or replaced everything else: shafts, tail hub, blades, belt, bearings and so on. Long story short, one of the tail rotor blade grips was knocked out of spec from a previous crash. Here's the kicker, the grip did not appear damaged and that's why I overlooked it several times already. I found it by comparing the tightness of both grips, the way they seat against the tail hub. One of the grips had more play than the other. So I replaced with new and now both grips have the same amount of play. Also, make sure all screws for the tail hub and tail rotor blades are perfectly straight.


Picture of the vibrating fin:

http://www.helifreak.com/attachment.php?attachmentid=53116&d=1214685817

[LockMD]

Some people just dont listen. I told you that!

[Redfire SVT]

Some people just dont listen. I told you that!


Lock, did you use telepathy?? :D

Seriously, I'm so glad to have found the vibration. I hope this helps a few guys out, because I was like this: :arggg:

[LockMD]

Quote:
Originally Posted by KevinV916 http://www.helifreak.com/easyaction/buttons/viewpost.gif (http://www.helifreak.com/showthread.php?p=738858#post738858)
Hey Skunky, is this kind of the same thing you're seeing? I just noticed it after my first crash losing control after a piro last weekend. I rebuilt the main shaft, the left servo gears, and the main gear. On one of the flights afterwards, I noticed the tail fin vibrating on one side. I don't hear any weird noises when spinning the blades so I'm wondering if I need to rebuild the tail as well. I was able to catch a pic of it so here it is:


Is the little pin that sticks out broke off? Mine did that too.....no biggie just a visual annoyance will not effect flying.


Sorry it wasnt you, I replied to Kevin. You all look the same :YeaBaby:

[KevinV916]

lol Lock :YeaBaby:

I haven't had a chance to troubleshoot mine yet, but I'll definitely check out the grips.. glad you got it worked out!

[ADHDJeff]

I'll be damned! I've been having the same problem and never would have noticed--thanks Redfire.

BTW, how much play is too much? My grips seem pretty sloppy now that I look at 'em. They certainly don't seem as tight as all of my head components and one isn't more sloppy than the other--but they do seem too loose compared to the rest of the heli.

[jayrat]

Thanx redfire, I'm in the middle of:arggg:a fin vibration troubleshooting marathon, been into the hub already, looked OK, but will replace tomorrow.

[Swashmix]

[quote=Redfire SVT;741550] I found it by comparing the tightness of both grips, the way they seat against the tail hub. One of the grips had more play than the other. So I replaced with new and now both grips have the same amount of play. Also, make sure all screws for the tail hub and tail rotor blades are perfectly straight.

Is the vibration completely eliminated? I have not wacked the tail on mine and there is the slightest of vibration noticable.Grips have the same play. It flies great, so I doubt I will change anything until required.
Also curious to know .... when you give the main rotor a bit of a spin by hand, can you hear a slight "swish noise " in the tail rotor? (I am assuming I am hearing the belt going around the tail drive pulley system.