Isolation CNC Milling
CNC machining techniques can be used to create printed circuit boards (PCBs) from copper-coated boards. Building PCBs using etching techniques involves the use of hazardous chemicals that need to be handled appropriately. Instead of etch- ing away all of the copper except the required circuit, milling removes only the cop- per on both sides of the circuit, thus isolating it and giving the process its name. It is not worth acquiring your own machine to create just a few circuit boards per year.Creating a small, single-sided circuit board using the toner transfer method costs about US$0.25 (excluding the board itself), and you will also need a drill to make the necessary holes. To get started making PCBs, you will need to spend about US10.8. If you need to create circuit boards regularly and don’t want to drill all the holes manually, a router is a great alternative option.
Note that the resolution you can attain using milling techniques is lower than that available through etching, which can be used to create traces with a width of 0.08-0.1 mm, whereas milling only allows traces measuring 0.2-0.3 mm. Tech- niques offering finer resolution are too expensive for general use and require the use of a motor capable of 50,000 rpm or more. If you already own a milling ma- chine or are thinking of acquiring one for other reasons, making simple one- ortwo-layered circuit boards is a great additional use for it.
