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WINDING THE COIL. Insert the hook-up wire into the hole (or run it along the top) until about 2’ extend from the round end. Now begin winding the other end of the wire around the bolt. Put on as many layers as you can, finishing at the handle and trimming off all but 2” of the wire. We’ll come back to the coil in a minute. But first the arm must be formed and installed.      FORMING THE ARM. Fold the 1/2”by 3”tin-can strip in half, lengthwise, so that it measures 1/4” by 3”. Doubling the tin-can thickness in this manner will give us the approximate flexing stiffness the arm needs. To fold the strip, simply scratch a line down the middle, clamp the strip in a vise at the line mark, and tap sideways with a hammer.      At about 1/4” from one end of the folded strip, drill a hole big enough to receive the machine screw. Then at the same end of the strip, make a 90o bend at a position such that when the long end of the arm is in place on the handle, the drilled hole will fall directly over the center of the bolt head. Assembling the Pencil      First the machine screw must be filed to a point. Do this by placing the nut on the screw tightly, then letting the jaws of your vise grip the nut. When a long point is formed, remove the nut (this helps re-shape any roughened threads). Now insert the screw in the arm. Replace the nut and tighten.