White Undercoat is very much like our Sanding Sealer with the addition of white colorant to provide primer undercoat for white/off-white finishes. High solids facilitate a fast film build. It dries tack free in 10-20 minutes. Recommended Accuspray HVLP atomizing sets: .072 tip and nozzle, No. 10 air cap. Click here for a guide for spray tip sizes.