- 1). Hold one disc magnet closed in one hand and a second magnet in your other hand. Bring them close together. If they start to attract, turn one of them around. Once they repel, use the marker to make a dot on the sides that faced each other. Pick up one of the marked magnets in one hand and repeat this procedure until all the magnets have been marked. Because poles of like magnetism repel each other, this marks the same pole on each magnet.
- 2). Set up the barbecue grill, fill it up, and light it. Place the steel disc over the center of the coals on the metal grill. Once the coals have fully ignited, put on the gloves and safety goggles. Light the propane torch and apply the flame to the steel disc. Move the flame back and forth over the surface of the disc, heating it evenly. Steel is easily magnetized and retains a magnetic field very well. It is even more easily magnetized when it is hot.
- 3). Take the disc off the grill once it reaches a dark cherry red color. Use tongs that are strong enough to lift and hold the disc easily. Bring the disc to the working surface and set it down. Place the washers on the steel disc with one in the center and the other four evenly spaced around the rim.
- 4). Place the five magnets carefully onto the five washers, marked side down. The washers are made out of aluminum, which will not melt at the temperature of the heated steel. Aluminum also is nonmagnetic, making it easy to remove the magnets after the process is complete. The washers will not block the magnetic fields of the disc magnets because aluminum has the same magnetic susceptibility as air.
- 5). Allow the steel disc to cool to the temperature of the air. The magnetic domains of the steel will all be lined up neatly because they move freely at high temperatures and the disc magnets are attracting them. Once the steel disc cools, its magnetic domains are locked in place and can no longer move about. They become frozen in their aligned position, and the steel disc will be a powerful magnet once the disc magnets are removed. Remove them by lifting them straight off the washer, being sure to wear gloves.
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