I was thinking of spray priming then spray painting the separate pieces of my great helm before assembly. I would like to use oil base paint as the final coat, but I've never mixed different types of paint and am unsure of the results. Anyone ever try this?

Well, I believe there are both oil and water based spray on primers to be had, so pick the one that matches the final coat best.

That said I think an oil based paint over a water based primer may work, but it wouldn't hurt to try out a small part first. Then if it fails just sand it off and try a different primer.

The easy way to remember it is that Oil sits on top of Water.

So you can paint an oil-based paint on the top of a latex primer. But not the other way!

I do agree with the previous poster, though, it's always best to pick one (oil or latex) and stick with it.

Thanks for the replies!