The Purple Painted Lady likes to use 400 grit sandpaper to lightly polish her painted surfaces to make them incredibly smooth prior to applying Clear wax. She cuts the 9" X 11" into smaller squares. When you lightly sand- you are breaking down any surface tension a slight rough feeling. However, something to keep in mind is that when you polish the surface you are compacting the paint and making the surface hard. This can be an issue if you plan to use Clear Wax after since the paint may not be porous enough to absorb the wax. (I hope that makes sense!)
So, again- this is perfect sandpaper to lightly sand your painted surface (typically after you have applied 2 coats.) But again, you are not burnishing the surface prior to waxing.
Use these Norton 400 Grit Super Fine Sandpaper Sheets (3-Pack) for a premium surface finish. The 9 in. x 11 in. sheets are made of aluminum oxide for great sanding and feature a zinc coating to help prevent color transfer.