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By Lee 11/13/2010
You need to polyurethane them. Paint it on and let it dry. Sand lightly, then repeat this step at least 3 times. They will come out really smooth, like glass, it is the same way you would do a piece of wood.
By pam munro 11/09/2010
Even regular paper-based coasters are not completely water-proof. Rather, they absorb the water sweating from the glasses.
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