Ripples in the paint. HELP!

[SteveSadler]

Polyurethanes are hard to roll and tip because they dry too fast. A slow thinner, or slow activator will give you more time to work with it but you need to roll it on thick and very quick in 2 directions and tip it with a good bristle brush vertically very quickly and leave it alone to flow out and set up. I takes practice as does spraying, which gives the best results. Sand the first coat, and leave the 2nd coat alone.