How to Make Paintings on Cardboard Last Longer
- 1). Seal the cardboard using an epoxy resin. Cover the cardboard completely and let it dry.
- 2). Before painting with acrylic paints, prime with gesso. If you are going to use oil paints, apply an oil painting primer. Let the surface dry.
- 3). Apply additional coats of primer as needed for a smooth surface until the cardboard does not show through. Let the surface dry after each coat.
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