Pitch Problem

[Scaff2151]

Hi Guy's

I hope someone can help with my problem. I've had my Belt CP v1, Stock Equipment for many years and have not yet flown it in anger apart from a slight tip over at low rpm trying it out (resulting in a cracked Blade and violent vibration.

Over the last few weeks I have resurrected my interest in Heli's. I have now cured the vibration with new main gears, bearings & shaft and also feathering shaft (which was bent). New Blades are CG'd, balanced, swash plate level and functioning BUT on checking Blade Pitch with motor disconnected only 1 Blade pitches the other Blade hardly moves? Collective at Midpoint Blades are zero, even when Idle-up is on still only 1 Blade moves to -6 to +9. I have checked and re-checked but everything seems in order (no binding or sticking) and I can't see any hairline cracks in any of the componentshttps://www.helifreak.com/images/smilies/BangHead.gif

If anyone can help it would be appreciated. Thanks in anticipation.

[Highspeed1964]

Sounds like you may have binding in the Flybar system. When you raise the collective (with Throttle Hold on so the motor is not spinning or better yet disconnect the motor), is the flybar rocking? If so, try holding the flybar stationary and raise the collective. You should then see both blades move with positive pitch.

Setups on flybar systems are a bit tricky, but from your description you seem to have a good handle on it. However, with the head spinning it is difficult to pinpoint such issues. Doing the test above, you'll quickly discover if there is any binding. Try that test with the blades at various positions around the rotation.

Most likely sources of binding in the flybar are:

1. The "O" link binding on the blade grips or rocker arm.
2. Bearing screws too tight.
3. Ball links not properly sized.

Check it out and get back to us with the results. We're here to help.

Hope this helps,

Highspeed

EDIT: Re-read your post. You do have the motor disconnected. Good on you for safe practices. Still, check for binding by holding the flybar level when moving the collective.

It's also possible that even with no binding, the flybar will have a tendency to "favor" movement on one side or the other. Again, holding the flybar level should result in movement of both blades.

[Scaff2151]

Hi Highspeed

Just tried what you have suggested holding the flybar whilst moving the collective and it works so now I will investigate the bearings & O ring etc. I can then move on to the Pitch Adjustment & Tracking at last.

Thanks for your help Highspeed it is Greatly Appreciated

[dayshaddow]

highspeed1964 is the man with a solid answer.one small thing from me is to check the feathering shaft screws, in the past i have managed to over tighten them and cause binding, the blades should move smooth as silk as they rotate. but like i said highspeed is on the money

[sutty]

Make a quick vid if you can and I can almost guarantee that one of us will be able to point you in the right direction after having seen it. If they haven't already of course.

[Scaff2151]

Hi

Just a quick update to my Pitch problem, having stopped down the feathering shaft and reassembled and not over tightened the nuts the problem was still there so more investigation. Finally, I found that one of the Fixed Links on the Blade Clamp Ball was sticky. So after gently rotating around itself and little Silicone Grease it freed itself. Well done again Highspeed you certainly know your Hobby.

Thanks again to Highspeed and Dayshaddow & Sutty for their input.

[Highspeed1964]

Fantastic work tracking that one down. Glad we were able to get you on the right track, but you solved it from there. And probably learned a good bit more about your bird in the process too, I suspect.



It's the fun of the hobby and the camaraderie of all the folks here at HeliFreak.



Happy Flying!

Highspeed