You painted an already white blank white?? “CONTAMINATION”. That’s Epoxy for ya! The next time you feel the need to paint a blank, do it on the raw foam. After of course you have filled and sanded the blank with Spackle or micro-balloons and Epoxy. Then laminate over that, hot or fill coat and sand. I think a lot of guys here on Sways are having problems because they wipe the blank down with soap and water, alcohol, acetone etc. Blow the blank off using air(no water in your compressor). Or vacuum with a brush attachment. You can also wipe it down with a tack cloth. Just wipe lightly so that you are not wiping wax from the cloth onto the board surface. I have done Epoxy in climates as far ranging as from the Pacific Northwest to Maui in the summer. Never had the problems that pop up all the time here on Sways when it comes to Epoxy hot coats or gloss coats. Don’t wash, wipe etc. Just blow it off really good with air. Don’t use Additive F in your lamination either. It’s got Xylene and Paraffin in it. Those two chemicals will cause your hot coat to bead up. It’s fine to mix a spoonful into the hotcoat resin. Additive F makes the hotcoat sand easier, that’s its purpose. If you do a nice Epoxy laminate, you shouldn’t need to do anything other than knock the laps down. You don’t need to sand or wash a laminated board before a hotcoat. That’s ridiculous!