A hair styling iron has a handle to which a heated barrel is mounted and a motor for moving the barrel. The iron includes a drive switch which is user actuable and connected to the control circuit for controlling operation of the motor. The control circuit includes a timer and monitors at least one change of state of the user-actuable drive switch to determine a starting time, and actuates an alarm, or another response, such as a reversal of the motor to unwind the hair, after an elapsed time measured from the starting time. The elapsed time may be user-selected or calculated automatically depending upon the length of hair wound onto the barrel, with compensation for barrel temperature.