<!-- 3. Make at least one positive cast from a negative cast or rubber mold. -->
<!-- 3. Make at least one positive cast from a negative cast or rubber mold. -->
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To make a positive cast from a negative cast, you will need a container at least the same size as the animal track. Lubricate the negative cast with petroleum jelly so that it does not stick to the positive cast. Then mix up some plaster, pour it into the container, and place the negative cast on top of the plaster. Press it in and vibrate it so that all the air pockets are removed and all the spaces filled. Leave it alone while it sets. If it was lubricated sufficiently, the casts should come apart easily after the plaster sets.
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To make a positive cast from a negative cast, you will need a container at least the same size as the animal track. Lubricate the negative cast with petroleum jelly so that it does not stick to the positive cast. Then mix up some plaster, pour it into the container, and place the negative cast on top of the plaster. Press it in and vibrate it so that all the air pockets are removed and all the spaces filled. Leave it alone while it sets. If it was lubricated sufficiently, the casts should come apart easily after the plaster sets.
Latest revision as of 08:39, 4 April 2021
To make a positive cast from a negative cast, you will need a container at least the same size as the animal track. Lubricate the negative cast with petroleum jelly so that it does not stick to the positive cast. Then mix up some plaster, pour it into the container, and place the negative cast on top of the plaster. Press it in and vibrate it so that all the air pockets are removed and all the spaces filled. Leave it alone while it sets. If it was lubricated sufficiently, the casts should come apart easily after the plaster sets.