Before painting your vehicle, you'll want to sand down the primer coat. This automotive video will show you how to block-sand the primer to prepare you for the actual paint job. It's actually a pretty simple step in auto painting.
In this video we are demonstrating how to block sand primer surfacer.
1. Apply guide coat to the surface.
2. Using a block and 320-grit sandpaper, cross-sand the surface.
3. Sand the surface until all guide coat is sanded off. If you sand through the primer surfacer and the epoxy, you will need to re-prime and block.
4. When all guide coat is sanded off and no filler or metal is showing, then you are ready to unmask.
5. Using a smaller block, sand harder to get areas and all edges.
6. Using a DA, inter-surfacer pad, and 500-grit sandpaper, sand over the surface where sealer and paint will be applied.
Now you're ready for final prep and masking for paint.