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View Full Version : Honey Bee King 2 Wear and Tear - Tail Rotor Vibration


borocouncilman
10-18-2007, 05:40 PM
I've been experiencing a high frequency vibration at the tail rotor of my Honey Bee King 2. This is a recent development. The airframe has about 30 flights (~ 5 hours of time) on it now with no major incident or accident. The canopy and skids don't seem to demonstrate any hint of vibration. The vibration itself seems to be limited to the tail rotor and housing like something is going wrong back there. Interestingly, I can see it in vibration along the tail rotor pushrod as well while the boom doesn't look like its buzzing.

Having already learned to fly on something else, the HBK2 been getting "exercise" from Day 1. I thrash it as my cheap heli. I don't do any hard 3D with it, but I do throw down hard and fast forward flight 2D transitions (including 180s and piros with 90 degree stops). I really make that little helicopter work.

With flight time, I have noticed that the head itself has really loosened up. It's not "too loose", but it definitely feels broken-in now. There is some play where there wasn't play before.

While it is difficult to pinpoint, I suspect that I may be "wearing out" something at the tail mechanism, but I really don't know. Belt is fine and was recently lubed with silicone -- something that I did after noticing the increased vibes. It hasn't made any difference.

Does anyone have thoughts?

P.S. For the folks wondering just how hard you can go 2D, check out scratches on my outrunner. While the servo cannot touch it on the ground, things are clearly flexing in flight. Check it out.

macdaddyec
10-19-2007, 07:41 AM
Have you lubed the bearings in the tail assembly? I lube all the bearings on my HBK2 after every third of fourth flight. Just a drop or two to keep things nice a free. Have you checked the belt guide bearings to make sure they are aligned and not binding as well. All I got and I hope this helps in some way.


Later

Eric

borocouncilman
10-20-2007, 09:58 AM
Well, I lubed things and it didn't affect the behavior. As I spun the main blades by hand, I noticed that even at speed the tail rotor blades were wobbling laterally in their grips. In looking at the mounting holes on the blades, I noticed that they had gone oblong under the stresses of flight.

I mounted a spare set that I had from my T-Rex. They are roughly the same size. The fit is snug, but not tight. The result is a much more authorative tail. Inspired, I'm going to start pulling things apart and see if I can further improve my HBK2.

crimsonrain22
10-25-2007, 09:26 PM
Sounds like a bent feathering shaft or worn out O rings on it on the main rotor head. Mind did the same thing. Doesnt take much to bend it its made of really soft metal. Quick easy check it takes 2 thin walled 5.5mm hex driver to remove it. It sets between the bladeholds under the main blade mount.

borocouncilman
10-26-2007, 07:13 AM
Feathering shaft is as straight as an arrow. The tail vibes are gone since I took care of the wobbling tail rotor blades.