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How Magna Doodle Works


In Action
Back view of a clean display
Back view of a clean display

Let's slide the magnetic eraser across the Magna Doodle and start with a clean display. The front of the display is blank (white), and the back has all the particles. They were pulled to the back by the magnetic eraser.

If you look closer at each cell, you will see that the magnetic eraser has aligned the particles to one side!

Close-up view of the cells from the back of the cleaned display: Note that the magnetic particles are aligned to one side (the direction of the sweep).
Close-up view of the cells from the back of the cleaned display: Note that the magnetic particles are aligned to one side (the direction of the sweep).

Now, if you move the magnetic pen along the display, the magnet on the pen pulls the tiny particles away from the back side to the front side, forming a line. Note that the magnet pulls particles from adjacent cells and aligns them in the direction of motion (in this case, to the right).

Close-up of a drawn line as seen from the front of the display
Close-up of a drawn line as seen from the front of the display
Close-up of the same drawn line as seen from the back of the display
Close-up of the same drawn line as seen from the back of the display

Because the particles are light and the liquid dispersion medium is thick, gravity will not pull the particles forming the lines back to the other side. What is written will remain undisturbed.

To erase the display, slide the magnetic eraser across the back of the display. As this is done, the magnetic eraser pulls the particles forming the lines from the front side to the back side and aligns them in the direction of the motion. The thickness of the liquid dispersion medium prevents them from floating to the surface, so the front side remains clean.

Erasing the Magna Doodle
Erasing the Magna Doodle

The Magna Doodle is a wonderful toy that allows children (of all ages) to draw and re-draw pictures and words without wasting paper or creating chalk dust. When traveling in a car on a long trip, one can draw for hours without creating lots of trash or having to sharpen pencils. Magna Doodles have been used by teachers to help students practice writing and learn words. Magna Doodles have been used in some unexpected places, too:

  • Some sports coaches have used them on the sidelines to outline plays for their athletes.
  • Because Magna Doodles are self-contained, they can be used underwater by divers to communicate.

There are many creative ways to use this wonderful toy. For lots more information, check out the links on the next page.