Here’s an easy to make catapult you can put together in minutes. The design uses the “bear clamp base” technique to harness tension. Once you grasp this technique, you can easily apply it to your own unique catapult designs. To get started, you need a few items from around the house.
1. Remove tape roll from an invisible tape dispenser. (Roll of tape should not be empty.)
2. Fasten the roll of tape to the middle of a cutting board. Do this by inserting strips of masking tape through the center of the roll and wrapping them to the bottom of the cutting board. Tighten the bond of the wrapped tape by taping over it in a perpendicular direction. Roll of tape must be fastened securely to the cutting board so that it does not wobble. (figure 1)
3. Rest a teaspoon against the roll of tape. Fasten the base of the spoon to the cutting board with rubber bands. To do this, wrap rubber bands around the cutting board, then lift slightly and insert the base of the spoon beneath the rubber bands. Now secure the base of the spoon to the rubber bands with tape. (This device is called the “bear clamp base.”) (figure 2)
4. Tape a cotton ball to the bottom of the bear clamp base to muffle the noise of the teaspoon when the catapult is flung. (figure 3)
5. Install a safety belt around the middle of the spoon so that it stays in place when the catapult is flung. To do this, insert a twistie tie (or pipe cleaner, etc.) through the center of the tape roll and loosely tie it around the mid section of the spoon. The safety belt should have several inches of slack so that it doesn’t constrain the thrust of the spoon when the catapult is flung. (figure 4)
6. You have finished the Mini Catapult Bear Clamp Base Design (figure 5)
How to Launch Objects: Bend spoon back, insert object, release.
What Objects to Launch: Cotton balls, fluffy end of Q-tips, cut up sponge pieces.
Three additional design ideas for use with the bear clamp base design:
In place of the roll of tape, try using:
– a paint roller (used to paint the walls of a house)
-a tennis ball
-two bars of soap fastened together
Of course, there’s no end to the variety of household objects you can use with the bear clamp base design. Good luck!