I havea TREX 600, I have been having wierd tail vibrations. not up and down but left and right, it isn't very noticeable, but the vertical stabalizer is vibrating like crazy. Could it be the main gear causing it or bearings? Everything is balanced, which is making it wierd. I noticed the 90*arm for the tail swash/servo had a bit of playbut I'm not sure if that is causing the issues. please any and all suggestions would help, I'll check everything!!

If it's not your gyro gain, and I'll assume it's not , double check all the tail rotor control & connections. I had a vibration like that once on my 500and it resultedin an unscheduled auto. Control arm was cracked before flight hadn't noticed it in preflight check, & it broke in flight right at the very end following a hard left hand banked turn

I plan to remove the rotor head, and spin her up again.  If that dosen't work then I am planning to do the same on the tail.  It could be the bearings, or one way bearing but they seemed ok  really have no idea and it's very irritating, I haven't flown in two days.  The only thing I have done is the upgrade to the helical cut gear on the motor, and main shaft.  </p>

I am also going to try to check the rpm, I don't think it's that.  man it's irritating! </p>

It's not the Gyro but it is affecting the gyro </p>

The looseness of your control linkage for the tail rotor will produce some very interesting results, including the one that you speak of.</p>

I would more than likely revisit the entire mechanical control line for your tail section and make the necessary repairs.</p>

it's more than just the linkage.the boom supports vibratelike crazy!!It's wierdI just noticedit happening the last fewslights. I'm going tochange the main bearings, I've noticed their a little worn. I have a ton of flights on this bird, I flew herat least once a day, sometimes twice last summer,150+ flights, in the dirtand dust, and desert heatwithout replacing anythingLOL.

Now the weather is good I havent missed more than a day in the last three weeks. I'm also going to changethe main rotordrive gear, and tail rotor belt. featheringshaft bushings, everything............... Another possibility is the Motor, which I think I'llreplace it with thetheAlign, ora scorpion. I probably will get the Scorpion so I'll be able to easily rebuild it., I just put so much use on the motor, I need to babable to rebuild it, out here in Iraq it's dirty, and dusty just plain nasty! I only wish I would have done this earlier, right now is prime flying time, and in two weeks I go home for leave. So I won't be flying until Late July.

Wich Scorpion should I go with? the 1900 and upgrade my ESC to the 100A
Well Guy's if you have any other suggestions it would be great!!!

Also If you know of a good websites for upgrades for the TREX 600 send me the links, I currently use Heli Direct, I have almost everything they offer.

Since it seems to be shaking the entire bird the mains are a good place to start, I think that the bearings for your tail drive gear would also be suspect. Also have a good look at your motor mount and the condition of your main drive gear. </p>

As for which Scorpion motor, I would think that the model HK-3026 V2  1000KV should be sufficent and the ESC should be the 60 amp as the 100 is overkill. You can find your upgrades and the Scorpion produts at the link below.</p>

http://www.helidirect.com/</p>

</p>

Watch Your Six, Tr1n1ty.</p>

I might have missed it above, but are you sure your tail rotor shaft is not bent?  I had the same problem, with the V-stab vibrating on my 450 and it was bad enough that I could even see it in the landing gear as well.  I  couldn't actually see the bent tail shaft but when I replaced it, the vibration went away.

Also, A couple of flights after this shaft swap out, my battery came loose and wound up in the dirt.  The good shaft was now bent very bad and so I swapped the shafts back to the one I was having the vibration with and the vibration came back.  I used a probe to see if I could see the shaft wobble but even with that, I couldn't see it the bent shaft. 

My suggestion would ne try another shaft.  They are cheap and if that isnt the issue you will have a spare in the event you need one one day.

I have a spare one from my old tail i'll try it tonight!!  I really want to get flying, I also am going to change the main gear.  then i'll do the bearing s when they come in.  thanks!!

I am not sure of your set up knowledge and I don't want to insult you so please take this as  friendly help only.

You will also get some odd vibrations if your head is not setup properly.  Make sure your mixer arms are both perfectly level with 0 blade pitch (mid stick in Idle up mode).  I know this can be an issue  because, I have also had this same issue in the past and by only adjusting the head linkages, I was able to remove all vibration.

I hope these suggestions help!

I'm fairly sure it's the Motor, no I know how to set everything up, I've been flying for a long time,I still Hate nose in and refuse to hover nose in LOL, On my simulators I fly 3D I just won't do it with my $3K heli.This is my first Electric so it isa bit different. So thanks, no offence taken. I don't want to replace it with another Align so what would you recommend? I want one that's fully rebuildable, and with easily available parts. I was thinking the 1900 KV Scorpion.

OMG you won't believe this,I found it the set screw on the pinion gear was not lined up on the flat spot onthe motor shaft. I guesswhen I changed the pinion and main gear to Helical cut I didn't have the pinion gear lined up, so it was defenitly this. Causing a high speed vibration. I re-installed everything and she fly's but it was late, I'lltry to get two flights intoday, to make up for my down time. I still would like suggestions on the Replacement motor, I want one that will just be perfect for my setup, I'm running the 13 tooth pinion and 188 main, so if that helps. I wasthinking of the 15 tooth and 188 main, I'm open toall suggestions!! Thanks guy's!

Hey just my two cents.....Ihad the exact same problems with mine and had well over 200 flights on it.....I dont know if you have changed any of your settings at all but I am always expiermenting with mine and found that when my head speed was to slow the vibrations in the tail were very bad. Might want to look at that.</p>

Well Thanks for that bit of info, and although I thought for sure it had to be the motor. After cleaning everything up and feeling out all the bearings,it turns out my swash plate is shot!

I never woudhave felt it untilI replaced my mainshaft.Itfeels notchy, and very rough to turn,I am thinking this has to be what is causing these vibrations, it's defenitly not a setup issue, and I felt it had to be a bearing on one of the hgh speed parts. I'll replace it and post the outcome.

'm going home on leave and just mailed my Heli to aghanistan because that's where i'll be mid July. I probably will not be able to do it until August. I'm defenitly planning on replacing the motor aswell to one I can upgrade any suggestions?