Originally posted by MARTINSR
Well, I hate to say it but you didn't ask here before you blasted I guess. I for one would have told you DON'T DO IT!!!!
Sand blasting creates "It is totally ruined throw it in the trash" kinda damage. I hope I am wrong for your sake, I can say with certainty it will take someone who really knows this stuff to save them if they are very badly stretched.
Understand that each grain of sand acted as a little hammer spreading the molecules on the top surface of the metal apart. You have increased the size of the top layer of metal only.
A shrinking disc may be the only way a novice may be able to save them.
Martinsr... I hate to disagree with you, but I have sandblasted many panels with no problems. I currently have a 67 Mustang Cpe, 31 Ford Model A Tudor, and 26 Ford Model T Touring, that have all been sandblasted. They were all blasted at home, with a small blaster from Sears, with 125 PSI from my 5 HP compressor. None of them have any damage from the blasting. The only times that I have seen damaged panels is when they were done by so called professionals, using high pressure blasters that were designed for heavy removal. I understand that if you hold the blaster stationary long enough, you can damage one, but I only use it to remove paint or rust.
I do have to agree, that is will take some work to get that panel straight now that it is stretched from blasting, since it is really hard to tell how much (area wise) it is stretched. Unfortunately, most blasting shields provide very limited viewing. That means that you can barely see what is being removed, let alone, if the metal is being stretched, or how much. Chances are that the operator never saw what he had done, until he had effected a large area. Unlike what we see in the collision work, where it is a small area that is stretched, and you can look and see what part is stretched, this may be an an area where "trial and error" might be the only chance. One thing about it. There is nothing to loose by trying/practicing.
Maybe Randy Ferguson has some tips that would help.