By Steve Nicholson
The body work continues. The filler work on the main body is finished. It's now ready for some 2K primer to start the block sanding process. The car was moved into the spray booth where it was prepped and masked for the primer. The areas that had been primered with epoxy were sanded with 180 grit paper so that the filler primer would adhere.
The body was wiped down with a Wax & Grease remover to remove any contaminants. Prior to applying the 2K filler primer, the bare metal areas were sprayed with epoxy primer. Unless the filler primer is DTM or "direct to metal primer" it is not recommended to spray it over bare metal. A self-etch primer or epoxy primer will need to be sprayed on prior to the filler primer. Check with your paint jobber or follow the tech sheet for the product you're using. Tech sheets are available from your paint supplier and by searching the web.
We applied four coats of the 2K primer with sufficient flash time in between coats. We then let the primer cure for a few weeks before we started sanding it. My personal preference is to let the primer get some time out in the sun to cure well. This will lessen the primer shrinkage once the paint is applied and give you a better finish. If you paint over uncured primer the paint will tend to get sand scratch shrinkage and the gloss level will not hold as well.
We like to start the block sanding process out with 180 grit dry paper. Block sanding is a lot of work and it's a dirty job. It also takes a lot or practice to do correctly. Make sure you wear a good dust mask too.
The hood was stripped down using a DA sander. It was then cleaned and sprayed with epoxy primer. The left side had been badly dented. As you can see in the pictures it looks really straight with primer on it, but it still needed some filler work to get it better.