Severe wobbling

[tigger]

Hello all,

My Honey Bee CP3 has a severe wobble at lower throttle. It's seems to smooth out once I get to lift-off throttle but as a complete beginner I was just wondering a) is this wobble normal at some throttle levels and created by a strange 'frequency' created at certain rotor speeds, or b) something more serious like a bent main shaft or feather shaft? I had a crash within literally 3 seconds of getting it of the ground on my first flight (not my fault – see my previous post!) and I'm just not sure if more damage has been done that I can see.

The swash plate, the tracking and everything else all looks fine to me and i can't see any kind of bent shafts either. Here is a link to a video which shows the extent of the wobble and at what throttle levels it starts at.

IMG 1256 - YouTube

Any help would be massively appreciated!

[SaneAdam]

Totally normal as it spins up, they all do it. Does it seem ok once airborne? If yes then i would say its fine

Bent shafts would result in serious vibes in the air too

[kroozing]

I had this when my blade grips were too tight. At higher speeds (hovering) the blades will straighten out and get rid of the wobble.

Edit: just had a look at the video and i think the main shaft may well be bent slightly. Run the motor slowly without the blade grips on and you should be able to tell instantly.

[tigger]

Hello again. Thanks for your help on this, I have some further info. After taking the whole main rotor section off to leave just the main shaft, i span it up from zero to half throttle – not a wobble or bad vibration anywhere to be seen. I then put everything back on except the main rotor blades – everything was fine again, no wobbles or vibes to report. Then, as soon as I put the blades on and try again we're back to square one. Serious wobbling and vibration – it still seems to settle down a little one they're really spinning up though, at around half throttle.

Being new to this, I can't compare this to any other heli's but i feel confident that this isn't right. There's no shop or club nearby so I'm really hoping that someone here could help me! Any advice would be great as I'm sure it's affecting the way it flies – and obviously as I'm learning to fly then I need it all to be working as best as it can so I know if the helicopter is doing something strange or if it's me!

[SaneAdam]

Sounds like the blades need balancing if thats the final step thats causing a problem. Do the blades look ok? No damage or anything?

Or, have you checked that you tracking is ok? Do you have a pitch gauge? Do both blades have the same pitch at mid stick? Might need to adjust a link

[SaneAdam]

I just actually watched the vid. That is totally fine. The problem is the training gear. Its causing the vibrations. Once you take off it will be ok.

Don't worry mate, honestly. There is nothing wrong there. Post a vid of it in the air and i bet its ok. It really is because you have the training gear on. The legs are flexi so at the low rpm the weight is being shifted like crazy which causes the resonating vibrations

I should have watched the vid from the start... lol