I don't know anything about painting and such, keep that in mind
Some areas on my car are bare metal, where paint is scratched off from previous dents or is peeling off, from what I assume is a cheap PO paint job. Also my rear trunk is bare metal now, but if I want to save everything from rusting, what do I use? Some sort of primer, but what? I'm not worried about cosmetics at this point.

Self-etching primer, followed by a coat of primer-sealer to keep the moisture out. Both should be available in rattle-can at you favorite local paint supply house.

QUOTE (Brew @ Feb 2 2006, 01:55 PM)

Self-etching primer, followed by a coat of primer-sealer to keep the moisture out. Both should be available in rattle-can at you favorite local paint supply house.

SEM is a good self ething primer. Should be available at your local automotive paint supplier.

Sherwin Williams makes this Kick ASS, zinc chromate acid etching primer. It is a two part catalyzed primer. Great for covering bare steel and fiberglass. Lay down a coat if it and then throw some regular polyurethane primer surfacer. DOn't leave any primer exposed to the elements long it will soak up water.

An exception to this are two-part epoxy primers, which are waterproof and hold up pretty much indefinitely. But they don't come in a spray can and it's expensive. The stuff I use - R-M Diamont Epoxy - probably is not even available in California because of environmental laws.