Homemade AC Induction Motors

An alternating current (AC) induction motor consists of a stationary part, or stator, which is physically connected to an external AC circuit and a rotating part, or rotor, which is not. The current flowing through the stator generates a magnetic field that induces a current in the rotor.

Stator

Create two stator coils by winding four layers -- approximately 440 turns -- of 32 AWG (American wire gauge) enameled, magnetic wire around two, 1-inch sections of toilet paper tube. Tape or glue each successive layer in place to prevent it from unwinding and leave a few inches of wire for motor leads.

Baseboard

Mount the coils at 90 degrees to each other on a baseboard made from an insulating material such as wood. Connect a 25 watt lamp in series with one of the coils to restrict the current flowing through it.

Rotor

Create a circular rotor, roughly the same size as the stator coils, from the lid of a steel can or bottle cap. Make a dimple in the center of the rotor with the point of a 1/8-inch nail and mount it on a straight pin driven through the baseboard between both stator coils.

References

• All About Circuits: Induction Motor
• U.S. Department of Energy: Improving Motor and Drive System Performance