The copper layers of a printed circuit board are the central focus of any circuit design, the other layers only support or protect the circuit, or simplify the assembly process. For starting PCB ...

CNC machining mills away copper using a CNC router and design software chemical etching uses UV light, photo-resist, and chemicals to remove copper CNC machining is safer and less wasteful, but slower ...

There may be nothing new under the sun when it comes to etching PCBs with UV light, but [Heliosoph] has brought finer control to a used face tanner he bought that now exposes his boards in ~50 seconds ...