All,

    At Northrop Grumman, we spent many months and thousands of Navy dollars studying various controlled processes to apply the new mandated low volatile organic compound (low VOC) coatings to achieve optimum adhesion, corrosion resistance and chip resistance etc., which included the observation of inherent yellowing of epoxy coatings.  The bottom line of the several inches thick report is;  Use clean, virgin grit-blasted metal substrate surfaces, epoxy primer and polyurethane topcoat.  The epoxy provides better adhesion, sealing and hardness, but chips easily and yellows.  The polyurethane is more color stable and chip resistant with lower adhesion and corrosion resistant.  Both respond favorably to elevated booth temperature and short time intervals between coats.  They didn't put all that nasty chemical stuff in the original formulations for nothing.  MEK, acetone, isocyanates ... all extremely harmful to humans but great for paint!  Without as much or with none of that nasty stuff ... very process sensitive at best, and lower to unacceptable results at worst.

    I vote for flat white epoxy primer, followed soon when only partially cured by semi-gloss or gloss white polyurethane topcoat,  over a scuffed substrate, surgically cleaned before scuffing and vacuumed after but not subsequently touched with paper, cloth or fingers.  Don't quote me, but a little extra nasty solvent would do wonderful things.  However, you might want to have a Democrat apply it for you!

Rod Pharis

Legacy

40% going on 30