In article . com,
stol wrote:

On May 20, 8:44 am, Michael Horowitz wrote:
I know that primer(over steel) is designed to provide a base for a top
coat, and (allegedly) you should not leave steel with only a zinc
chromate coating (although I've seen steel fuselages zinc chromated
only and they appear in good condition).

I have read that if you appy a 2-part epoxy primer, you don't need a
top coat. Anyone else read that? - Mike

If you like the color of the primer then a top coat will only add
extra weight. IMHO

Ben

The paint companies around here (PPG, for instance) say that primers
will not protect the steel long-term -- you need to apply a top coat to
seal it.

Check with a good auto/marine paint company -- they have a wealth of
information at their disposal.