Tips for applying touch-up paint after performing car repairs include thoroughly cleaning the surface area with soap and water and allowing it to dry completely before painting. Another tip is to use sandpaper to remove all dirt, debris and loose paint prior to applying touch up paint. Use a spot sander to prepare surfaces when applying touch-up paint to minor dings and scratches.
Always obtain touch-up paint that is the proper color; when unsure what color paint to obtain, refer to the vehicle's manual or consult with the dealership. Use paint syringes to apply an even coat of paint when touching up scratches and cracks, and apply paint with a 1/4-inch artist's brush when painting larger areas. Use a putty knife, screwdriver or sandpaper to remove loose paint and rust spots that may keep the touch-up paint from properly bonding to a surface.
Use 150-grit sandpaper to cleanup any rust spots, and use 600-grit sandpaper when feathering painted edges. Use a clean rag to wipe away sanding dust. Apply rust converter to affected surfaces and allow it to dry completely. Some rust converters can harden and function as a primer coat, whereas others require the application of a separate primer coat prior to painting.