Tail Shake

[Hermit9832]

So a very small, I would say quarter to half inch left to right tail shake has started occurring on my fbl mini titan. I have had no issues with vibrations or tail wag or shake before. The heli has about 40 or 50 flights on it.

I was playing around with the governor mode in the ESC last night, set the head speed to 2800 rpm and took it out front to see what it was like and the flight was uneventful. This morning I took her out for a little day flying and as soon as I settled in to a hover the tail starts to do this very fast left to right shake, almost like a vibration, you can actually hear it.

I had the governor set for a 2500 and 2800 head speed and when i switch between head speeds it goes away but as soon as the head speed settles the shake comes back. I figured it was something with the governor so i switch back to fixed end points and the shake is still there!

I have adjusted the gain down to the point where the tail blows out and its still there.... I just dont know what could have changed between yesterday and today besides me playing with the governor but undoing my changed should have fixed it...

Im going to reset beastx and reprogram the heli and see if this fixes the issue, its really all I got left. Just figured I would post on here and see if anyone else has this occur.

PS I would love to rip apart the head but I for the life of me can not get the screws loose from the feathering shaft... they are on there TIGHT! There always seemed to be a little to much play in the head...

[nickyd]

Tail: take the linkage off the tail and check the slider moves smooth as silk.
Check for out of balance tail blades too maybe.
If you try gov mode again drop the gov gain too.


Feather shaft
Make sure you use good hex drivers to unscrew bolts. Try applying heat to screw with a soldering iron. This will loosen any loktite.
I have one shim on my head which i placed next to the dampener to reduce play. Check if you have either red or black dampeners. I believe the black may be a little too soft.

[Hermit9832]

Thanks for the reply Nick! Are you the only person that posts on here lol? I have already looked at the dampeners and they are black, matter of fact I ordered about 200 dollars worth of spare parts to keep just in case of crashes and one of the things I ordered was a spare head block and it came with black dampeners too....

The play is in the blade grips, horizontal and lateral just seems like a lot. It was a ARF kit and I figured they would at least put the head together correctly.

[JWeber]

There are a lot of tools for removing the feathering shaft bolts. Most specifically, the second one.

Tarot makes ones that has 4 different size one way bearings so that you can use it on 450 and higher sized helis. I hav that one and it works great. Also get a good set of hex wrenches. When I first started, I bought an EXI heli tool kits and they were junk. I now have Align wrenches and I like them. If you want to go with the Cadillac of tools, people swear by Thorpe or Scorpion.

One tip for the tail slider is to polish the tail shaft with a product called Mother's Mag or other metal polish. It will remove any imperfections in the shaft that you can't see. I had sticking every once in a while and since I've done that, it's buttery smooth. Just make sure to remove the shaft before you use the polish and clean it thoroughly after you're done, because if it gets in your bearings, it will destroy them.

[Hermit9832]

Thanks for all of the replies everyone!

So I checked everything over mechanical wise and didn't find anything wrong. Rest BeastX and reprogrammed, test flew the bird and still had the shake. After a little brain storming I came to the conclusion that it had to be the ESC, the problem didn't start until I tried to set up governor mode.

I reset the ESC and put it back in to fixed end points and re-calibrated the throttle end points and test flew again and boom problem solved.

I thinking the issue was when I tried to setup governor mode I never calibrated the throttle end points to began with. This was cause a very small but very fast motor surge and I think this is what was causing the tail to shake... you could hear it, lol.

Well, I set up governor mode again and have not had a chance to test fly it but I'll let everyone know how it goes.



Update: In governor mode and everything seems to be working fine! Thanks again for all the input.