How to Make Rocks Out of Cardboard
- 1). Tear or cut corrugated cardboard into small pieces. The amount of cardboard required depends on the size of the rocks that you want to make.
- 2). Soak the cardboard in water overnight to turn it into mush.
- 3). Blend the wet cardboard in a food processor to pulp it. Do this in small batches, saving the pulp in a plastic bag.
- 4). Squeeze out as much water from the pulp as possible.
- 5). Mix the pulp with white glue until it reaches a dough-like consistency.
- 6). Form the pulp dough into a rock shape with your hands, smoothing the surface by rubbing it in small circular motions.
- 7). Set the cardboard rock in the sun for several days until it is completely dry. The larger your rock is, the longer this will take.
- 8). Sand the cardboard rock with 120-grit sandpaper and a rotary sander if you want a smooth rock. If you are happy with a slightly lumpy rock, you do not need to do anything after it is dry.
- 9). Seal the rock with a coat of clear, waterproof varnish if you plan to place it outside.
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