I have applied a single layer of Zinsser Oil Based Primer and want to know if one single coat should be enough ? The directions on the can says two coats. I thought I needed to use an oil based solvent primer due the darkening of several paint test spots on the wall but now believe that the darkening of the paint might be due to a bad paint match but possibly still could be due to some contaminant in the original paint. The original post can be seen here [url]http://www.doityourself.com/forum/painting-staining-all-interior-exterior-surfaces/552266-dark-spots-walls-after-application-paint-help.html[/url]

I just applied one coat of stain to a door that faces the outside. What I will eventually do is put a layer or two of Miniwax Helmsman spar urethane clear finish. I was actually planning on applying a second coat of stain, but it came out a bit darker than I thought it would be. Now I'm wondering if I need to apply that second coat of stain at all. Is there any benefit for the wood, to get a second coat of stain? I don't need to make the color any darker at all, and the wood will be protected by the coat of finish. So is the only reason for applying stain, to change the color of the wood--or does the stain also help protect the wood?