The weirdest vibe issue I ever had...at a roadblock L14

[OICU812]

So I will make this as short as I can. I consider myself to be quit knowledgeable on the Logo 14 as I have built 6 of them between crashes and rekits etc.

Recently I had a bad one where the Jesus bolt broke in mid air, short of a few electronics it was a write off.

So I get it all together to find I have a real high pitch freq vibe travelling through the entire heli. Enough of a vibe blow out the front pulley bearings after one flight. So as per usual I start with the tail.....

I remove and replace the tr shaft even though it is new, bearings as well that are new to. Try it again and the vibe is still there, the horizontal fins vibrate on ends about a quarter inch in height. Thinking well,,,, I will just take off the Horizontal fin and see what happens,,, the vibration actually enhances and gets worse so put the fin back on..

Now I am like ok well it has to be travelling from the frame portion.. Change out main shaft even though it is new and install one I roll on glass. Change out main bearings as well to Boca ceramics that are brand new as well. Still vibrating.. :arggg:

Take head off completely and feel main shaft while motor is running and feel a super high vibe. Now I am like ok maybe the motor mount got bent..? Change that out to a new one I have and guess what vibe is still there.

So....now I think well maybe something from tail still somehow is making this vibe, disconnect tail completely from heli, vibe is still there.

Now thinking well it has to be the motor than....?
Good lord change that out and try 3 other motors, vibe still there.

Change out the gears both main and tr drive ,,, vibe still there
Change out auto hubs and even the tr drive hub to, vibe still there...


Man oh man, first real struggle I have ever had with any Logo heli ever period. I think this one has me defeated to be honest. I have double triple checked everything in the world on this machine, basically rebuilt it over twice and I can not get rid of this dam vibe. :shock:

Only one thing that I have not changed which I have a hard time thinking is the ESC which is a Jazz 55-10-32. I can not see why it would or how it could create a vibe of this sort plus I really do not want to spend 250+ USD if it is not going to solve it. At this point I have spent a whack of dough to figure this out without success. Love the heli man, but when is enough-enough??

Sorry about my rant post, thinking maybe someone has something to say that might create a spark but honestly I do not know of anything I have not done to figure out this mystery........
:dontknow :?: :bomb:

[Motions]

WOW! I had a ghost like that but found it was the tail bearings.

Have you tried changing the skids? :mrgreen: I think thats the only thing left. While reading the post I was thinking "motor" but you changed that.

Best thing to do, which is how I find gremlins, is to take off as much as possible and spool it up. If there's no vibe, start adding pieces until it comes back. You could even start by taking out the main gear and spooling up just the motor.

You have a pretty good one there.

[Klinger]

There's nothing left to change out, except the skids as mentioned :lol: . Damn thats a hard one, are the frames new or repaired. Could there be a crack in the frames weakening them. dont give up! Let's know what you find.

[OICU812]

Frames are brand new, everything on the heli is brand new, I mean everything. Tail bearings and all bearings have been replaced and triple checked greased etc,,,. Skids you say...? Weird ok I will try that one, I mean why not, but what exactly was your issue and how did you solve that one...?
Removing all the gears and having the motor just running did that too, still a vibe somehow moving throughout the entire heli. Ugh.... :roll:

[jmiceli11]

Is the motor mount Aluminium? Is it new? You could have bent it slightly and that could result in a vibration. Ask me how I know. :dontknow

[Motions]

Shawn, just kidding about the skids. But if turns out to be the problem I'm gonna LMAO.

So your get vibes with just the motor? It HAS to be the motor but you said you tried 3 of them. You got an ornery ghost in that machine.

If the motor mount is tight and the motor is tight, I can't see how that would cause vibes but I'm not saying it can't. Put it on the shelf and get the 500 going.

[OICU812]

I have tried both plastic and aluminum motor mounts, I have 5 on hand. PS will get 500 going when it comes in :(. Living in the north means mucho delay getting things from USA. My biggest mistake was selling off my L14 backup machine and 2 other 50 sized helis, never again. Come this winter I will be in full build mode and have a few spares of each, sucks not having anything bigger than a 450 rex to fly. :badair:

[MrMel]

Just some pointers.

Tried different Tailblades?
Main blades warped/out of track? (even if not visible it can make a really bad vibe, check with pitch guage)
Try stiffer boom-support (if its self-induced vibes)
Belt pully, check it, if it runs true.
Main gear wobble?
Balanced the head on a dubro prop balancer? (without blades but with paddles)

[OICU812]

I have this vibe with the entire tail disconnected and no main gears even on. It is like the frame is somehow resonating the vibrations from motor and amplifiying them fiercly. I might have a frame set that was drilled out wrong somehow now I think or perhaps this esc is sending bad power waves creating it through motor, pretty confusing. Once I get the other ESC from my HFX frame build I will try that and see what gives, after that it is game over pretty much.

[MrMel]

Aha, if it dont help with another esc, try just loosening all screws on the frame and tighten them again.

[Daniel Jetschin]

:shock: :shock: :shock: :shock: :shock: :shock: :shock: :shock:

[OICU812]

Yea that was my next thought, run it with head off, loosen and watch and listen, that is about all that is left Fredrik, lol. :bomb:

Danny you think I should send it to you in Germany and you can tinker with it on your spare time?? :dontknow lol. :glasses2:

[Jag]

I have been chasing a Phantom Vibration on my Logo 14 as well...tried everything and can't figure it out either?

Weird thing is that my vibration is gone one day but when it sits for a few days and then I fire it up the damn vibration comes back?

Seems to really set on after a couple minutes of flight?

Any ideas?

I have tried new shafts/bearings/head etc...never been crashed so it has no damage...It also has an almost new Actro 32-3

[Lorents]

This is really weird Shawn!

If it is a high frequency vibe it is more likely to be caused by the motor somehow (since the tail is eliminated). Only thing I havent seen mentioned here is the motor pinion. have you tried another pinion?

[OICU812]

Yes sir I have, I set the heli aside for awhile as it was raging me out of my mind..... I will tackle it after my L5003D build :).

[Klinger]

Hey shawn, did you ever find the cause to this yet or more to the point how's the 500 coming?

[kgfly]

I feel your pain ! I have a very similar problem with my EP8 :(
There is a vibration that is affecting the gyro and causing wag. The vertical tail fin is buzzing away no matter what I do. I have tried/replaced:

* 2 motors, 3 pinions, 2 gyros, 1 and 2 gyro pads, 2 tail servos, various head speeds
* dynamically balanced the head, main blades and tail blades
* new main shaft (x2), main bearings, main hub/one way, main gear, entire new tail, tail shaft

The vibration remains at low amplitude with just the motor (no pinion or main gear/shaft/head), gets stronger with a pinion, much stronger with main gear/shaft, stronger again with the head and most intense with the main blades.

The heli is flyable but still has a slight wag. Driving me nuts :arggg:

[Ace in the hole]

Ya, when these heli's decide to give you fits they can just about drive you out of your mind. I have a vibe in my L10e that was driving me nuts first part of the year. I set it aside and have been flying other stuff for a while, now that I have calmed back down I think I'll give it another go. Good luck with yours Shawn.

[misskimo]

I know what it is , I KNOW WHAT IT IS! the last thing you didnt try :arggg:
you know when looking somewhere for something , and the last place to look , is where its at , thats how it goes 90% of the time.

ex. One time in my life , I lost a pretty brown eyed, brown hair with a tent of red ( built like a Brick Sh@# House) young lady. We were together all the time. Laughed together, Played together. :smokin: Just a jolly good time. it was like a match made for each other. POOF! While out on a friday night, dancing the night away. We got seperated. I looked Every where ! couldnt find her! Mothers house , Dads House ! Her girfriends house! just like she left the face of the earth!
Aw! then I woke up ! MAN! why couldnt I have slept alittle longer till i could have found her!
But years later , I found her , and shes my Wife now ! :smokin:

well for whats its worth , alittle laughter can over come some of the anger dealing with the Phantoms that all helis seam to get at one time or another , or they just have them all the time. :wink:

[OICU812]

LOL Tony.

Well last night I started to rebuild ground up. Not going to happen overnight that is for sure but I am starting it again and hopefully something will turn up or simply change by doing so. I am changing the frames as well as I suspect perhaps to tight or something of an alignment thing maybe........

[Motions]

Hey Shawn, have you tried changing the kit? :lol: Maybe to a 600?

Do you even have your 500 yet? Shipping to Canada must be a killer. :arggg:

[OICU812]

Got the 500 yes, built yes but very few flights and waiting on some 22,23 tooth pinions. I am on the line for a 6003D just waiting on that to be released as well. And yes shipping, customs, duty to Canada blows for sure from the US. Getting things from over the pond however is super fast and cheap being part of commonwealth. :wink:

[OICU812]

So I just got it all back together ....again.... hoping some nice weather will arrive soon and I give it one last go. So far on floor for test spoolup it looks good. New everything, I mean everything this time, every last bolt, if she vibes again it is going off a cliff, lol.

[ozace]

I am dying to hear how this turns out. Nothing is more frustrating in this hobby.

[OICU812]

Wooohooo, so a new set of frames and a whack of other stuff later it seems to be finally happy. I actually opted to not heat my frame this time and tried the G10 frames from "rdespins" here on our forum. Ron "owner" made me up some frame doublers and I stacked in the area where the motor can was so I did not have to heat anything up at all, which was pretty cool. I am thinking my motor mount or my metal tr drive hub was tweaked now. Anyhooooooo happy it is running well finally and I really missed my Logo 14. Flying my backup machine for awhile my 600 rex was ok, but just no wheres near the same machine, not one bit actually.