Although professionally-produced printed circuit boards are drilled out automatically by computer-controlled drilling machines, the hobbyist can still obtain good results by using a high speed hobby drill and a drill stand. Drilling out a printed circuit board can be a messy process which generates a lot of dust and swarf, so it is best performed in a garage or workshop.
Instructions
1 Clamp the hobby drill into a drill stand. Because the drills bits are so thin, they are extremely easy to snap, especially if they enter the PCB at a slight angle. A drill stand ensures the drill is aligned correctly, and allows you to create a straight hole through the board. Make sure the drill you are using is relatively high speed, around 20,000 rpm is ideal.
2 Insert the drill bit into the drill chuck. Tungsten carbide drill bits should be used, as standard high speed drill bits are quickly worn away by the fiberglass materials used to make the boards. A 0.8mm drill bit is suitable for drilling holes for most components, and should be used for the initial drilling. Holes can then be re-drilled with a larger drill bit if a larger hole size is required. Spare drill bits should always be kept, as even with care drill bits can snap frequently.
3 Set up a good source of light above the work. The PCB solder pads are often very small, and good light is essential to check the positioning of the drill.
4 Position the board on the drill stand so the drill bit hits the center of the relevant solder pad when the bit is lowered. A scrap piece of soft wood should be placed under the PCB to catch the drill bit when it penetrates the board.
5 Smoothly lower the drill bit into the PCB. Do not force the drill bit through the board, as it is likely to snap. You should let the bit penetrate the board at it's own speed.
6 Repeat the procedure with a larger size drill bit for any holes used by larger components.
