3D printers are incredibly useful for making plastic parts cheaply and relatively quickly. But, that’s not all they’re good for. 3D printers have many of the same components as other automated machine tools, so you can convert them into plotters, laser cutters and engravers, and even light-duty CNC mills. You can also use a DLP (direct light processing) 3D printer to etch your own homemade PCBs.
These days you can get professionally made PCBs delivered to your door in less than a week at remarkably low prices. However, that doesn’t mean that homemade PCBs don’t have their place. If you expect that you’ll need to go through a lot of prototype revisions, those one week lead times can add up quickly. You could certainly use traditional transfer etching methods to make PCBs at home, or you can follow Electronoobs’ guide and use a DLP 3D printer to make PCBs are a lot cleaner.
DLP 3D printers work by exposing photosensitive polymer resin to light, which just so happens to be one way you can etch PCBs. First, you take your PCB design and turn it into a 3D STL file in Blender. Then apply photosensitive film to your PCB blank, load the STL file on your DLP 3D printer, and place the PCB on the build plate. When it runs, the 3D printer will expose the photosensitive film. After that, you can dump the PCB in etching solution baths, just like you would with traditional methods. Without a lot of additional work this will really only be viable for single-layer PCBs, but the results are great.