Do you have a picture of what you are taking about with these rings?
What did I do wrong with the Zoar cause both were not balanced out of the package according my balancer.
Ha better yet make us a video Mark
the links I posted show what I am talking about with the APC props,, look and see,,
the rings only come with electric props, my bad, but the links describe how to treat the glow props,, basically the small hole is drilled after the fact and should never be the centering point if at all posibble, go read the links I had in my email
as to Xoar,, I can only surmise your balancing method may be flawed, its very easy to bend the shaft on a balancer,, what are you using to balance, how long have you had it, and have you triple checked to insure its accuracy?
I have friends who fly the big Gas powered RC models, swinging a 18 or 20 XOAR prop, he does the same as he does with apc props, takes them out of the package and bolts them on,, ( no I do not agree with this method) and has never had a problem,, ok well there was one time it was way off balance, but that was after he smacked the ground taking off and lost a blade LOL