Trumple

Hi there, sorry if this is in the wrong section.
I'm just trying to get my new RC Heli to work properly. The first time I flew it straight out the box, it worked perfectly!
I went to an open field and flew it around a bit, then my friend asked to have a go.
Of course, the moral of the story is don't trust your friends with your expensive stuff!

So anyway, he crashed it into the ground and I went over to it. It looked to be all in place, with no physical damage. However, when I increased the throttle to let the rotors spin, the heli had a massive wobble all of a sudden. The whole thing shakes in phase with the rotors, but the problem is we don't know why!

I have checked the blades, they all seem fine (this is a beginner heli so it has a gyroscope (the kind with weights attached at each end on top of the rotors)) and the gyroscope was fine too, although it did look a little bit odd (by this I mean it was slightly bent one side, and down on the other) It looked as though it was made this way though, and the poles of the gyro are very strong, so I doubt the crash could have bent it in such a way

Do you masters of these things have anything to help a poor newbie out? I will try and get a video of it soon.
I really would like to fly this heli, it was great fun while it worked!

Thank you very much, and merry Christmas!

nothinbetr2do

welcome to the forum and r/c heli's

your going to have to take it apart and check to see if the main or feathering shaft is bent. these are things the always bent in a crash. after you get the parts off the heli, roll them on a flat surface(glass table) you'll know right away if they are bent. because they won't roll, they wobbble. do the same for your flybar rod to. take it off and take the weights and paddles off and roll it on the same flt surface
also, it will help to know what heli it is?

Trumple

Ah I see. I have not taken anything like this apart before, so i'm not really use what part of the the feathering shaft I should be looking at (a quick google searched showed a vague location)
Also, where is the flybar rod?

If you could explain that would be a great help

Thanks very much

grawyl

What heli do you have? This may help others in their diagnosis.

Trumple

It is a Double Horse 9053 (Cheap and cheerful, I know)
After looking at some videos (I cannot see it very clearly but) it looks as though the balance bar/ weighted gyro is supposed to be perfectly straight. Mine is bent. Does anyone know if I should straighten out the balance bar again?


Thanks

grawyl

Yes. The Flybar (balance bar or gyro as you call it) needs to be straight. You can try to straiten it yourself and it may work ok. If you damaged the blades their is a good change you bent one of the main drive shafts. The inner shaft in a Coax helicopter is usually fairly susceptible to bending. If this is bent it will not fly well and will vibrate. I suggest taking it apart and inspecting both drive shafts for damage. If they are bent you will most likely need to replace them as straitening them is very difficult.

Keep in mind that the spinning rotor heads need to be perfectly balanced and that any imbalance will cause it to shake. Kind of like a tire on your car being out of balance but it affects a helicopter much more severely.

Trumple

Thanks very much for the advice.
Since the rotor blades fold in on themselves to protect them, I think it is more likely the flybar is bent. I will straighten it out tomorrow and tell you how it goes.

Edited:
Works fine now, thanks for the help!