To successfully paint over solvent-based paint, you need to ensure proper preparation to allow the new paint to adhere correctly. This primarily involves cleaning the surface and removing the sheen.
Here's a breakdown of the process:
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Clean the Surface: Thoroughly clean the existing solvent-based paint to remove any dirt, dust, grease, or other contaminants. Use a suitable cleaner, such as trisodium phosphate (TSP) or a TSP substitute, and rinse well with clean water.
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Remove the Sheen: Sand the surface to remove the existing sheen. This creates a "key" or rough surface that the new paint can grip onto. Use sandpaper with a medium grit (e.g., 120-180 grit) for this purpose. Make sure to remove all the sheen.
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Prime (Optional but Recommended): Apply a primer specifically designed for bonding to glossy surfaces or for transitioning between oil-based and water-based paints. This step can significantly improve adhesion and prevent future peeling. Some primers are self-etching and are excellent for creating a strong bond.
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Apply the New Paint: Once the primer is dry (if used), you can apply your chosen paint. Follow the manufacturer's instructions for application and drying times. Depending on the type of paint and the desired finish, you may need to apply multiple coats.
Summary: The key to painting over solvent-based paint is cleaning the surface and removing the sheen so the new paint can properly adhere.
