Oxygen

[crvc]

Ten years ago I did a bare-metal restoration of a 914. I used generic bondo to fill dents. I primed the bare chassis then towed it to the body shop for paint. They charged $1000 for just the chassis with no doors or hoods. So I did the other body parts myself with a borrowed sprayer. I didn't have a compressor so I painted using a tank of compressed oxygen from the oxy-acetylene welder. When I sold the 914 this year I saw some of the chassis was starting to bubble under the paint. My dad, who knows more about cars than God, said the oxygen mixing with paint is the reason I got rust bubbling under the paint. Is that true?

Eventually I'll do the paint myself on my '67 restoration but I'd rather not buy a compressor if I can avoid it.

[bhowden]

Ten years ago I did a bare-metal restoration of a 914. I used generic bondo to fill dents. I primed the bare chassis then towed it to the body shop for paint. They charged $1000 for just the chassis with no doors or hoods. So I did the other body parts myself with a borrowed sprayer. I didn't have a compressor so I painted using a tank of compressed oxygen from the oxy-acetylene welder. When I sold the 914 this year I saw some of the chassis was starting to bubble under the paint. My dad, who knows more about cars than God, said the oxygen mixing with paint is the reason I got rust bubbling under the paint. Is that true?

Eventually I'll do the paint myself on my '67 restoration but I'd rather not buy a compressor if I can avoid it.

Boy, the local fire department must really like having you in the neighborhood! You can also get tanks of Nitrogen or CO2 or even air which would be considerably safer. While I am no expert, I would not have thought the O2 in the spray gun would have anything to do with it. The compressor only supplies the vehicle to get the paint to the car. Once the paint is on the car, it is wet and then the solvent evaporates out of the paint leaving a paint film (at least with enamal or lacquer paints which is probably what you were using). I would be more suspicious of leaving it to long after metal prep and before painting or not using an etching metal prep at all. 10 years is not totally out of line for non epoxy type paints, especially if you live where it is wet or salty in the winter.

Brian