Painting With Hot And Cold!

Glow in the Dark Thinking Putty allows you to "Paint with Light" using our Blacklight Keychain. Hypercolor Thinking Putty opens up a new horizon: "Painting With Hot and Cold."

For this experiment, you'll need some "canned air" and a hair blowdryer. The canned air is available for a few bucks at any office supply or computer store and is used for dusting keyboards and electronic equipment. I'll let you figure out where to get a blowdryer by yourself.

The canned air contains a non-flammable liquid stored under pressure which expands into a gas once it is exposed to the atmosphere.

Thanks to a phenomenon known as adiabatic cooling, this jet of "canned air" can be fairly cold -- just what we need to change the color of Hypercolor Thinking Putty.

Adiabatic cooling occurs when a gas goes from occupying a small volume to a large volume. There is a certain amount of heat inside that small volume, and when the gas expands the amount of heat has to be divided evenly thoughout the new volume. This makes the air cooler.

You'll notice this effect on propane tanks and spray cans -- as you allow gas to escape, the container and remaining liquified gas gets colder.

If you decide to try this experiment yourself, read all the warnings on the back of the canned air. This is important! I'd like to point out a few important hazards before we continue.

• Only perform this experiment outdoors. The chemical inside the canned air is heavier than oxygen. Even moderate spraying indoors can replace breathable air resulting in YOUR asphyxiation.
• Keep the spray away from hot glowing surfaces (ovens, stoves, grills, etc). The heated surfaces can decompose the canned air into Hydrogen Fluoride (aka Hydrofluoric Acid).
• Do not get silly and start spraying the canned air onto bare skin. It is easier than you think to get frostbite from the cold. It might not be a bad idea to wear long sleeve clothing and gloves.
• Be smart. 'Nuff said.

Stretch out a 1 lb bag of Hypercolor Thinking Putty. It's fun to leave it in direct sunlight for a few minutes and watch it change color, but we'll use the blowdryer to speed things up a bit.

Set the blowdryer to its lowest setting and then figure out the furthest distance from which it will work. USE THAT DISTANCE! You don't want to get the putty so hot that it will become molten and a) burn you or b) become stickier than you can imagine. You're painting with heat!

Now spray some canned air onto the putty! You're painting with cold!

Try it with a friend: One on blowdryer and the other on canned air...dueling color changers!

Pretty neat, huh?

Success with the canned air is all about technique. First, you need to hold the can upside down. You want to be steady on the trigger to control the width of the spray on the Thinking Putty. Also, you need to have just the right tilt to the can. You want to tilt it enough that the air comes out cold but not so much that it makes a freezing mess of liquid pouring everywhere.

If you decide to try this yourself, send me some cool movies and I'll put them up on the website!