Hello, right I have an old post about painting flashing in the daylight. I tried a few diffemrt paints from cheap to expensive. Whatever I did I could get rid. I thought I was lapping but it seems where flashing is, it’s like clusters of pimples. It’s fresh plaster on board. I can’t sand all the pimples out. Will using a long nap get in and even this out? It’s so annoying