Measure the magnets and note the length and width. Measure the width of the aluminum ribbon strip.
Cut a piece of PVC to a length 1/2 inch greater than the magnet, using your dremel tool. This is the mounting plate upon which the magnets and ribbon will go.
Set the guide on the plunge router to 1/16 inch. Release the safety lever on the plunge router guide, pull the depth guide upward and set it to 1/4 inch. Use the measurements on the side to determine when you've set it to the correct depth. This prevents the router from cutting any deeper than 1/16 inch.
Route out two parallel channels in the PVC, both large enough to house a magnet. The gap between the channels must have a smaller width than the aluminum strip.
Slot a magnet into each channel.
Wrap the aluminum ribbon strip around a bottle cap and roll the cap along the length of the strip, so the ridges of the bottle cap imprint on the strip. This corrugates the strip, giving it tension relief and making it more durable.
Cut a length of aluminum ribbon to a length 1/4 inch longer than the magnets.
Lay the ribbon between the two magnets so its edges overlap them. Solder the edges of the aluminum to the magnets.
Cut three 1-inch pieces of microphone wire and a 1-inch piece of ground wire
Solder one piece of microphone wire to the end of the each magnet. Solder the other end of those wire to the input terminal on the base of the XLR jack.
Solder a piece of ground wire to the aluminum ribbon. Solder the other end to the ground terminal on the XLR jack.
Remove the bulb and batteries from the flashlight. Unscrew and remove all other internal components. A gutted flashlight makes an ideal housing for a microphone because it is sturdy and narrow, with a wide head.
Glue the mounting plate into the inside of the top of the flashlight housing.
Cut a piece of steel mesh and shape shape it so it fits over the top of flashlight housing. Steel mesh is pliable, meaning sufficient force will make conform to the shape of flashlight.
Wrap three thick rubber bands around the mesh to hold it in place. The mesh protects the ribbon from damage.