The first thing to do is to make the search coil. This can be made from a wooden sandwich of three circular pieces of wood. These are fitted together (glued or tied with string) and used to make a former to wind 19-25 turns of the insulated (enamelled) copper wire. That's the 32 SWG wire on our list. Remember to leave about 30cm of wire at each end of the coil so that you can connect it to the electronics a little later on.