Materials Needed:

  • Large rubber band (goes around the battery to hold the leads)
  • Magnet
  • 2 jumbo-sized paper clips
  • Small gauge magnet wire (enameled wire)
  • Marker
  • Connecting wire
  • D-cell battery
  • Packing foam or rubber eraser to use for the base
  • Sandpaper (medium grit) 

Printable PDF instructions can be downloaded here.


  1. Wind the wire around the marker about 12 times. (More doesn’t help; the coil gets too heavy for the ends to hold it steady.)
  2. Straighten each lead so that you can hold one in each hand and spin the coil without causing it to wobble. Be patient - the coil must spin smoothly for the motor to work.
  3. Sand one lead so that it is shiny on all sides, the entire length of the lead.
  4. Sand the whole length of the other lead, only on the top half. The sanded parts of both leads should be shiny.
  5. With your eraser or foam block flat on the desk, set your magnet on the center of the block. The curved magnet should open “up” like a bowl.
  6. Stab one end of each paperclip into the block, and bend the other end so that one lead can rest on each paperclip. With the leads resting on the clips, the coil should be suspended just above the magnet without touching it. For best results, keep the clips just far enough apart so the coil does not touch them when it spins.
  7. Each wire gets clipped to one paperclip. Clip the other end of each wire to the battery. The electricity must pass through your coil to complete the circuit. If your coil jumps when you connect the battery, that is a good sign!
  8. Give the coil a push start to start it spinning. The half-sanded end works like an on-off switch each time the coil turns over, so that it gets pushed a bit faster each time it goes around.