Axe CP- What is wrong?????

[nicadflyer]

OK, I have been flying RC for over 20 years, so I thought I would try a helicopter. I bought the Axe CP. I tied it down to a work stand and powered it up. I had the blades up to just over half speed when the heli tried to shake it's self apart
Banging Head.
I disconnected the motor and played with all the controls and found that one of the blade grips did not move when the collective was adjusted. I fixed that issue but the heli still shakes at the same speed. At half speed it is smooth as can be and blade tracking looks very close. I have not had the in the air yet.
Has any one had a similar issue with theirs?

[jeffk]

Blades out of balance? I know the instructions say they are "Perfectly balanced" at the factory but I seriously doubt it. If the tracking is off even a little, you'll get vibes too.

Balance your blades and track the beastie and I'll bet most of your vibes go away.

[alucard]

Hello there another thing to consider to is the blade tension it need to be igual tension if the blade are to loose it will cause some vibretion when you speed it up So like jeffk said balance your blade with tape chek the trak and the tension. In the DVD tell you how to do a proper tension to the blade. :D

[nicadflyer]

Thanks for the info guys. I have dug a little deeper into this issue. First, I don't have a any way to balance the blades, but I did weigh them. They were within 1 Grain (437.5 grains /oz). The head seems to be off center, it has a slight wobble. I powered up the heli without the blades and there was NO vibration. The blades do not track the same from one side of the heli to the other with the sticks at neutral. The heli still vibrates like mad just above half throttle but smooths out (?) at higher RPM.

[Ray K.]

When I got my Axe, there were a couple things that were installed incorrectly. Take a careful look at the bearings inside the blade grips- there should be 2 radial bearings and 1 spacer in between them. Also, make sure that the feathering shaft screws (the ones that hold the blade grips onto the shaft) are absolutely tight. I had some very severe vibration as a result of one of those being just 1/2 turn out. Since you haven't flown it yet, I find it impossible to believe that your mainshaft is bent.... You said that your blades are very nearly perfectly balanced, but try this- remove the blades, and bolt them together in a reasonably straight line. Then hang the mess from a string, and see how well they balance then. It's possible that the CG of the two blades is slightly different, and that can cause vibration also. Finally, check your flybar and make sure that that sucker is *perfectly* centered- I use calipers when I set mine up, and try to get the sides within .01mm of each other. Make sure that your flybar paddles are totally flat relative to the flybar cage, and you could weigh those for balance too.

If none of these things straightens you out, then I'm mystified...

Good Luck!

-Ray

[Iceman140]

nicad flyer,

Do this to see if the CG is the same on both blades. Get a long thin bladed phillips screwdriver with a real smooth round shaft. Put only the shaft on a totally flat level surface, a formica countertop will do. Then place the heli blades close to center on the shaft. Slowly roll the screwdriver shaft left and right until the blade is balancing. With a felt tip marker, dot the blade exactly above the center of the screwdriver shaft. This is an approximate CG. See why the thinner the shaft the better? Do the same with the other blade and if your CG's are the same chances are they're balanced enough for now. When adding tape to balance later, add tape at the CG of the blade. Check for tight ball links too. A ball link may only bind at one spot. It's all cheap injection molded plastic after all. :mrgreen:

Let us know what you find.

Ed :dontknow