As our El Camino Resto Mod Project finishes up on the pre-final paint processes of, “apply stuff and sand it off” over and over again; A common query is, “ What is under all the stuff and how did you get it to that point?”
Before we begin our paint removal techniques session, let’s have a point of understanding. Do we really need to take this baby down to bare metal to refinish it? Look, it is your car. You do what you think is best. In my opinion, you have to go to bare metal to do the job right. Why? Call me if you really don’t know.
As you may recall in the last issue, we tackled the rust paint removal on the frame. As for the body sheet metal, the process is the same – but it isn’t. The thickness of the frame metal is much more forgiving than the body sheet metal. Older pre 50’s cars had a standard 12 to 14 gauge metal which handled more aggressive grinding and blasting. The 16 to 19 gauge modern sheet metal bodies are not as forgiving.
Improperly prepped sheet metal will eventually start to rear its ugly head and begin to show signs in the final paint. It may take months or years to show up, but it will show up and there will be no question of why you are seeing blemishes under the final paint. Blemishes in the paint are another issue.
Forget all of the “possible” approaches to get down to bare metal. As far as I am concerned, you only have two options. Only one if you are going to do it yourself.
1st option, or the only DIY option: Blasting with sand or broken reconstituted glass. These are the only media that will cut the rust down to bare metal properly. Both methods can cause metal distortion. Glass generates less heat. Keep the blast nozzle at a low angle to the work piece. Coming at the metal with the nozzle at 90 degrees or sightly less is going to create problems. Try to finish the body blasting in as little time as possible. Then coat the bare metal ASAP with Epoxy Primer ONLY. Remember primer is not the same as Epoxy Primmer. If you can’t finish all the body parts in one day and coat them, do one part today and another tomorrow. This is more time consuming due to paint clean up, but you will be happier with the results.
2nd method – Dip Bath, with dip neutralize bath and sealed with E Coating. E coating is that black paint stuff you get on factory new parts.
There are three (3) important elements of this approach. Don’t take short cuts even if the guy who might do it says, “it ain’t necessary.”
Body and parts get submerged in a bath that removes everything but the metal. (It will remove the metal if you leave it in for too long). Body and parts are submerged in a second bath. I said submerged, not sprayed or rinsed. The 2nd bath neutralizes the chemical in the 1st bath.
If you don’t neutralize the 1st bath, it will work out of crevices over time and attack your paint – I speak from knowledge. Finally, have the body and parts E Coated for ultimate rust prevention. As an acceptable alternative rather that E Coat, an Epoxy Primer coat immediately after stripping is OK. You can’t wait until you get it home to do the Epoxy Primer.
That’s it! A good solid base for the re-birth of your classic!
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