I am making small aluminum bowls out of sliced aluminum rods. The Sketchup file is attached. I am considering the OpenBuilds mini mill which could cut the dimensions I am looking for, or modifying the C-Beam mill so that it has a larger z-axis travel. The inner bowl needs to be as smooth as possible. 1. Can the mini mill do it? 2. Which bits would I need to get the smoothest inner surface?