I would have to do some digging in my tech manuals for that. But Dupont is another company that washed their hands of soda blasting. PPG and Dupont DON'T do anything without handing each others hand. Meaning if one company comes out and says something about a certain technique then rest assured the other company wont be far behind.
A good friend of mine who works for PPG as a PPG rep(not some counter lackey) is one who informed me about the PPG ruling on soda blasting.
From my understanding they came out with the non warranty with soda blasting because they were taking it in the shorts because of complaints and redos because they cant get paint to stick.
This is a somewhat new thing as of about 1-2yrs that they wont warranty paint with soda blasted cars...Eric
