Great job on the ring. Hopefully you can have it cast and show the results here.
I design and make rings for a living. My technique is a bit different than casting. Because I make rings from titanium, I have to machine them with a CNC lathe and CNC milling machine, rather than cast. That limits me to simpler designs. I use MoI to produce renderings, and I use software I designed to create the G-Code for the machines.
I do use a 3D printer to produce custom ring sizers for customers. Michael wrote a MoI script for me where I create a 2D profile, enter the ring size & width, and MoI builds a set of 5 rings sizers in half-size increments. It's a real time saver. http://moi3d.com/gallery/viewitem.php?id=908
