Guys,

I did the balance for the blade first as Tomflier said. After that I machined a blade stiffener (see picture) and reran the helicopter. I slowly bend the stiffener a tiny bit at a time, and finally the helicopter's blade got balanced. One notice is the blade stiffener (I called that myself) can be purchased at many hobby stores, but I found it easy to be made and made one. I hope this would be a good tip for us. Thanks Tomflier.

MTDV