How to Make a Concrete Leaf Cast
- 1). Mound the sand on the plywood for the leaf mold. A depression in the sand will leave a high point in the mold. A raised area will create a dip in the mold, as if for a birdbath. Cover the sand area with a large piece of plastic. Lay the leaf face down on the plastic.
- 2). Put on the dust mask and gloves. Pour one part concrete, three parts sand and a handful of fiberglass fibers into the bucket and add the recommended amount of water according to the package directions. Use a shovel to stir the mixture until it is the consistency of frosting.
- 3). Pack the cement on the leaf with your hands. The thickness varies depending on the size of leaf. A 6- to 10-inch leaf should have a 1/4-inch thickness, while 10- to 14-inch leaves should have a 1/2-inch thickness, and anything larger should have a concrete thickness of at least 1 inch. For the largest leaves, cut strips of chicken wire as reinforcement and bury them in the concrete.
- 4). Press the concrete to the edge of the leaf and at the same time pull the plastic wrap in toward the leaf. This will make a barrier all around the edges of the leaf to keep overflow from occurring. Let the concrete dry for three days to make certain it is cured all the way into the center and to reduce the chance of breakage.
- 5). Peel off the leaf. If the leaf doesn't come off easily, let it dry thoroughly and brush it off with a broom or soft-bristled brush. Moisten the piece of burlap and lay it over the concrete. Keep the burlap damp, and let it stay on the mold for two weeks. This helps ensure the curing process is slow, creating a stronger concrete.
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