I originally built this toy using a Canadian nickel coin. Canadian nickels are made of pure nickel, unlike U.S. nickels, which contain so much copper that they are not magnetic. You can build the toy with the nickel or with the Radio Shack rare-earth magnet. The rare earth magnet will work a little better because it loses its magnetic properties at a lower temperature, and thus the toy can use a candle instead of an alcohol burner for its heat source. Some particularly nice tiny rare-earth magnets can be found in our catalog.

This heat engine is very simple. We suspend a small piece of magnetic material at the end of a pendulum. A large magnet is placed near the pendulum, so that the small piece of material sticks to the large magnet. The magnet should be close enough that the material never rests at the bottom of the pendulum’s swing, but instead jumps up to the magnet. A candle is placed under the material, so the flame just touches it.

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Some years ago I built a geodesic dome out of ½ inch galvanized steel electrical conduit, to serve as an aviary for chickens and small parrots. I wrote a computer program to calculate the proper lengths of steel tubing, and draw the diagram shown below:

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The Best Of Paper Toy. Just One Piece Of Paper . No Glue. 6 Face - The best bloopers are a click away

Crazy Paper Cylinder ! How To Make ! - Watch a funny movie here

Unbelievable! White Or Black. Crazy Paper Cube. - Awesome video clips here

As I turn this little paper sculpture inside-out, it changes colors. First yellow, then blue, then red, then green, and then yellow again. I can keep turning it inside-out, cycling the colors, as long as I like.

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Do you have someone in your family who you know has used your things, but insists that they haven’t touched them? Or do you have a problem with people going through your things and personal belongings? Well, what you need is one of these…

You will need:

* newspaper
* cardboard box card
* tissue paper or kitchen roll
* PVA glue
* paintbrushes
* poster or acrylic paint
* scissors
* felt pen

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