Well, time to put on the thinking cap! For the first try, I had the foam laying directly on the aluminum table. The problem was that the foam chips couldn't clear so they created a ball of melted plastic on the bit, which wreaked havoc on the part. So, I placed wood spacers under the foam to keep it about a half inch up. This worked great. Now I just need to get the cad file correct!
After a half dozen or so attempts, things started to look promising. However, I mis-calculated the open side of the bearing and cut the wall too thin. I also learned that you need to put hop and skip tabs in the drawing to keep the part fixed until the milling is done.
It sure is nice to see the CNC mill up and running though!