How to Make an Hourglass Out of Plastic Bottles
- 1). Empty out two 2-liter soda bottles, and rinse them out with water. Allow the bottles to dry completely for one hour.
- 2). Fill one of the soda bottles halfway full of sand. You can find sand at any home improvement or hardware store.
- 3). Press oil-based clay into the opening of the sand-filled bottle. Cover the hole completely. Repeat this process with the other bottle, covering the hole with the clay.
- 4). Push a pencil through both clay-filled openings. This will cause the openings to have a pencil-sized hole through them.
- 5). Place the empty soda bottle on top of the sand-filled one, and line up the openings. Wrap duct tape around the two stacked openings to secure them tightly together. When you flip the bottles upside down, the sand will flow from one bottle into the other like a sand hourglass.
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