Which action best prepares a surface for paint after sanding?

• A. Clean the surface thoroughly
• B. Apply filler
• C. Start painting
• D. Remove masking tape immediately

Answer: (A)

After sanding, the surface must be free of dust, oils, wax, and other contaminants so the paint and primer can bond properly. Cleaning thoroughly removes the fine particles created by sanding and any residual lubricants or polishing compounds that would create a barrier to adhesion. The best approach is to wipe with a tack cloth to pick up dust, then use a wax-and-grease remover or a dedicated degreaser, followed by a final wipe with a clean, lint-free cloth. Let the surface dry completely before applying primer or paint.

Filling is a preparatory step done before sanding to smooth imperfections, and starting to paint without cleaning risks poor adhesion and an uneven finish. Masking tape should be managed according to painting guidelines (typically removed after the paint has set to avoid peeling), not as the first post-sanding step.