Contemplating CNC Milling Circuit Boards
Another activity that we will be investigating in addition to CNC engraving is the potential of making our own circuit boards. Mechanically speaking, milling circuit boards are very similar to engraving. Both types of tasks stay within a very shallow range of Z, and would suffer little impact by our wobbly Z axis. Milling boards could involve larger tools than a pointy engraving tool, but they should still be relatively small and not drastically strain our limited gantry rigidity.
Experimentation will start with the cheapest option: blank circuit boards that have a layer of copper on one side. ("single-sided copper clad") This will be suitable for small projects with a few simple connections that we had previously tackled with premade perforated board and some wires. For example, Sawppy's handheld controller could have easily been a single-layer board. We would need to go to dual layer for more sophisticated projects like the Death Clock controller board, and the ambition for this line of investigation is for the machine to make a replacement control circuit board for itself.
We don't yet know how feasible that will be. As the level of complexity increases, at some point it won't be worth trying to do board ourselves and we're better off sending the job to a professional shop like OSH Park. And the first few boards are expected to be indicative of amateur hour and a disaster, hence we didn't care very much about the quality of the initial batch of test boards. They were purchased from that day's lowest bidder and second lowest bidder on Amazon. (*)
But even though circuit board milling is mechanically similar to engraving, the software side is an entirely different beast that will need some ramp-up time. And before we start cutting metal in the form of a thin layer of copper, we need to pay some attention to the machine's needs.
(*) Disclosure: As an Amazon Associate I earn from qualifying purchases.