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Purpose:
To learn how to make an electric motor
Materials:
One ‘D’ cell alkaline battery
One wide rubber band
Two large paper clips
One rectangular ceramic magnet
Heavy gauge magnet wire (the kind with red enamel insulation, not plastic coated)
Sandpaper, file or razor blade
Optional: glue, small block or wood for base
Procedures: It might be easier to do step 2 before step 1.
1. To make your coil, wrap the wire 3-7 times around the battery, leave about an inch tail at each end. Remove the coil from the battery. Wrap the two tails around the coil so that the coil is held together and the two tails extend perpendicular to the coil. Be sure to center the two tails on either side of the coil. Balance is important.
2. On one tail, use the sandpaper or file to completely remove the insulation from the wire for a length of about 0.25-0.5″ from the end. On the other tail, lay the coil down flat and scrape off the insulation from the top half of the wire only. The diagram below if for an end view of each end of the wire.
3. Bend the two paper clips into the following shape (pliers may be useful here)
4. Use the rubber band to hold the loop ends (on the left in the above drawing) to the terminals of the “D” Cell battery.
5. Stick the ceramic magnet on the side of the battery–it is a magnet, it will stick on its own.)
6. Adjust the tails of the coil so the bare wire touches each paperclip – this may require wrapping the tails around the coil another one or two times.
7. Place the coil in the cradle formed by the right ends of the paper clips. You may have to give it a gentle push to get it started, but it should begin to spin rapidly. If it doesn’t spin, check to make sure that all of the insulation has been removed from the wire ends. If it spins erratically, make sure that the tails on the coil are centered on the sides of the coil.
8. It might help to bend the tails of the coil a little bit to keep on its cradle.
9. The motor is finished.
10. Feel free to change and adjust anything that you think will allow the motor to run better. Different shape coil? Different magnet configuration? Different orientation of the sanded half vs. coil?