What does a primer-surfacer do on the substrate?

A primer-surfacer is specifically formulated to improve the quality of the surface prior to applying the final paint coat. It serves an essential function by filling in scratches and other imperfections on the substrate, creating a smooth and even surface. This enhancement is critical because a well-prepared surface leads to better adhesion of the topcoat, ensuring a more uniform and durable finish.

In addition to filling imperfections, primer-surfacers often also provide good hiding power, which helps in achieving a consistent color when the final topcoat is applied. This function is vital in painting and refinishing processes, as it helps reduce the visibility of the substrate beneath and contributes to the longevity of the finish applied over it. A proper understanding of this role is important for anyone involved in painting and refinishing, ensuring a high-quality end result.