Where I work we used to use a milling machine similar to the CC to cut circuit boards out of copper clad phenolic boards for custom stuff we needed in a hurry. Basically you lay out traces and pads, drill holes etc. where you want them and at the correct sizes. It seems it would be very similar to cutting around the outline of features to isolate from the rest of the copper plane. The bulk of copper left became the ground plane. The machine was a bit different in that the piece stayed stationary and the truck moved x,y,and z. Used bits very similar to dremel bits. Was wondering if anyone had tried anything like that on one of these machines. Not sure how the accuracy could be achieved. If you layed out what you need in something like turbocad and then imported it into designer, what would be the best way to insure that all your dimensions stayed as they should be.