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Ever since I bought a copy of The Best of Making Things: A Hand Book of Creative Discovery, originally published in 1973, I have had my eye on this project: the Salt Pendulum. I love the combination of science, art, and kinetic fun! We added the idea of using colored salt for a more vibrant project and I have to say it was worth it. Even my always skeptical son decided to join in the fun for awhile. To make your own colored salt visit my tutorial here.
How to Make a Salt Pendulum
- Colored Salt We used (4) 26 oz. containers worth of salt
- Thumbtacks (optional)
- Beads (optional)
- Hot Glue
- Black paper or board
- A doorway for hanging the pendulum
- Step One Punch three evenly spaced holes near the top of your funnel.
- Step Two If you are using thumbtacks push them through the holes and hot glue a bead onto the pointed end to protect fingers.
- Step Three Cut three equal lengths, roughly 10” to 12”, of string and knot them together at the top.
- Step Four Tie the loose ends of the strings to the thumbtacks. If you are not using thumbtacks, thread the string through the holes in the funnel, knot them securely, and add a dab of hot glue to the ends.
- Step Five Figure out where you will hang the pendulum. We hung ours outside on our porch between two hooks we have on the underside of a beam. The hooks are roughly 4 feet apart. The pendulum can easily be hung in a doorway as well. Just hang two hooks or place two nails on either side of the top of the doorframe. Because the salt is messy make sure it’s in a doorway or location you can easily clean afterwards! Once the hooks are in place tie a taut piece of string between them.
- Step Six Cut one long piece of string and tie it to the knotted strings on the pendulum. Center it on the upper cross string and tie it. Remember that the salt will weigh down the pendulum so either tape the end of the funnel shut and pre-fill the pendulum when hanging, or hang the pendulum about a foot above the floor to account for the weight of the salt.
- Step Seven Place your black board/paper underneath the pendulum
- Step Eight Tape the bottom of the funnel shut and fill it with one of the salt colors. Make sure the salt is not clumped together but nice and loose so that it easily flows out the funnel.
- Step Nine It’s ready! Ask your child to either untape the bottom or untape it and let them swing the pendulum gently. Off it goes!
We made several “drawings” by layering the colors of salt and changing the direction of the swing each time. When you’re ready to start fresh, empty your salt into a bowl and save it for another project. Yes, the colors will be mixed but I don’t like to waste anything!
I absolutely loved how this project turned out. It felt like we were making planetary drawings; now if I could only figure out a way to preserve them….