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[Solved] High Vibrations

Posted: Sat 26. Mar 2016 15:47:13
by Swift Phantom
Hello,

I have a Goblin 380 and the Spirit FBL and I haven't been able to sort out some tail wag that I have no matter what headspeed/tail gain I run, even with the speed up tail pulley.

So today I did some tinkering with the Spectrum Analyzer and found something interesting. My tail (Z Axis) is showing massive vibrations (316-350), and vibrations of about 63 on my X Elevator axis, with 9-15 on my Y Aileron but when I disconnect the tail belt from the main shaft it goes below 20 on all three axis.
This is the Z (Rudder) axis running as "normal."
This is the Z (Rudder) axis running as "normal."
So I'm pretty sure the vibrations are in the tail, but I wanted to check with you guys and see how you would proceed and what I should be looking for.

Steps I've taken:
1) Remove tail blade grips - No change
2) Remove Pitch slider - No change

Because of how this heli is designed, if I remove the tail shaft I can't rule out bearings, the supports that hold the bearings, or the tail pulley.

My guess is that it is the tail shaft, but I just want to make sure I'm on the right track and the figure out the best way to trouble shoot the problem.

Thanks,
Nathan

Re: High Vibrations

Posted: Sat 26. Mar 2016 18:16:59
by Swift Phantom
I found the issue. I had installed SAB's belt tensioner and while spooling up I was looking over the heli and noticed that the tensioner was jumping around a bunch, so I took it off and everything is below 20 on the whole heli.

Even though it's been a lot of trial and error, I'm really enjoying the Spirit. Can't wait to get it fully tuned!

Re: [Solved] High Vibrations

Posted: Sat 26. Mar 2016 23:44:15
by ZeXx86
Perfect you have found it.

In case of any question feel free to ask.