>It's a common misconception that primer will protect against rust. Primer
>designed to be porous, so the top coat can penetrate and lock into it.
>primary purpose is to improve adhesion, it does little or nothing for rust
>protection. It's the top coat that locks air away from the steel, so it
Randall is correct as usual. In one of my past lives, I inspected the epoxy
primer on the parts used to build the A-10. I had a tool that measured the
primer thickness and it had to fall within a plus/minus spec. I forget what
the spec was, but it was REALLY thin, almost transparent. I wrote up the
primer for being too thick many a time, but never wrote up too thin primer.
Too thick and the paint wouldn't stick, they said. Of course this was
aluminum alloy, and may not apply (pun intended) to steel.
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