What type of sandpaper is appropriate to use when applying enamel?

Using 320-A sandpaper when applying enamel is appropriate because this level of grit strikes a balance between being coarse enough to effectively prepare the surface while still being fine enough to prevent excessive scratching. When working with enamel paint, the surface needs to be smooth to enhance the final appearance and adhesion of the paint.

Grits in the 320 range are commonly used for final sanding before applying a finish coat, as they create a smooth surface without risking deep gouges that can show through the enamel or require additional work to fix. This makes 320-A a suitable choice for achieving a desirable finish when working with enamel coatings, ensuring that the end product has a clean and professional look.

Other sandpaper grits, such as those that are too coarse or too fine, could lead to issues such as not properly preparing the substrate or not providing the necessary bite for the enamel to adhere appropriately. Hence, 320-A sandpaper provides the optimal surface preparation for applying enamel.