I am going to walk you through the process of prototyping a Printed Circuit Board using a laser cutter and supplies from your local Radioshack and hardware store. This is a process I have perfected after several prototypes I created as part of my thesis, modular//neuroid
Step 1: Prepare the board
Remove the bare copper PC Board from the plastic being careful not to get oily fingerprints on it. Place it on a clean, suitable spraying surface (newspaper or cardboard are great). Using flat black spray paint (I used Krylon brand) coat the copper 3 - 5, allowing time for each coat to dry before applying the next. If your PC Board is double sided, be sure to repeat this step for the other side. By the end of this step, your board should look completely black, no bumps or unevenness, and certainly no copper visible at all.
Step 2: Prepare your file
Most laser cutters use vector files to print. Ours (an Epilog Legend 36 EXT) can print PDF or Adobe Illustrator files. To build a correct schematic, export the footprint of your components (in this case female mini-USB ports) as vector files from Eagle or Fring. Import this to Illustrator, and build your own traces. Keep in mind a few things:
• we want the laser cutter to burn away everything that is NOT a trace, therefore the background is black and our circuit is white.
• 1.5pt lines are the smallest that can be drawn
• For text, no smaller than 5pt font, and should be placed as a negative inside of a box, otherwise it will get etched away
• If you are making double sided boards, finish your front side and then mirror. This is the easiest way to keep things lined up with each other.
• Be as efficient as possible : cram as many as you can together, it will make cutting boards later easier as well