Hello friends, I am trying to make a system, a convex cylindrical surface, and I want to make a scraping curved jewelery event in this system, how can I do to be used in the design, curved to varying degrees as we consider the ring or the inner surface of the outer surface of the ring to be engraved, and these surfaces can be curved outward or inward bending also how can such a system is changing the arches radius sizes?

You may want to check the Chris Botha thread here http://www.machsupport.com/forum/index.php/topic,11446.0.html
He gives tips on how he produced the various pieces as well as the CAD/CAM he is using.

Hope this helps.

Tweakie.