This cool contraption is lots of fun to watch in action! Hang it from a sturdy spot, such as a branch or a basketball hoop, and use it with tempera paint thinned to the consistency of heavy cream. To achieve a true spiral shape, spread your paper over a flat surface, such as pavement or a piece of cardboard. For our more free-form look, a less even surface will do.
Use scissors or a craft knife (an adult's job) to remove the base of the 1-liter bottle.
Trace the cut edge of the bottle onto the plastic container lid, then cut out the hole.
Cut a hole about the size of a bottle cap, in the bottom of the plastic container.
Use the hole punch to make three equidistant holes 1/2 inch from the top of the bucket. Cut three 24-inch lengths of clothesline (not pictured). Push each through a punched hole and knot it.
Push the bottle kneck through the hole in the base of the container and screw on the flip-cap.
Fit the lid onto the container and mark where the clothesline knots touch. Remove the lid and cut notches there.
Fill the space between the bottle and the container with sand, then replace the container lid.
For the main line, cut a length of clothesline a few inches longer than you'd like the pendulum to hang.
Tie a spring clip to one end and a steel ring to the other.
Slip the second ring onto one of the lengths of clothesline tied to the container, then knot all three lengths together.
To hang the container from a tree, toss the main line over a branch, then thread it back through its metal ring to cinch it. Attach the spring clip on the main line to the metal ring on the container. To hang the container from a basketball hoop, slip an S hook over the rim and hang the main line. Use the spring clip to attach the container. Note: The container should hang 2 to 3 inches off the ground, so you may need to adjust the length of the main line accordingly.
Spread paper under the pendulum. Close the flip-cap spout, then fill the bottle with thinned tempera paint or cornstarch ink. Quickly open the spout and push the container out over the paper.