When I used to paint locomotives in the late 80s we tried water based paint for a short while. From what I can remember it was a very hard finish when it cured and we didn't use a clear coat on it. The big problem for us was cleaning the equipment. We used a pressure pot for painting the loco's and with the long hose used for carrying the paint it made it really hard for clean up when switching back and forth between water base and polyurethane paints. Water and polyurethane just don't mix, lol. I do remember we just went back to base coat, clear coat polyurethanes. It was just simpler.
