I was using Krylon clear coat with gloss for acylic paint and for some weird situation part of the plastic part which became glossy on the first coat would become dull or flat as if it got sanded when I applied another coat on top of it. I do my coats every 20 - 45 mins. I done it on another plastic as a test with same result. By the way there is no paint on the plastic. Am I doing something wrong?
Just a guess, but maybe the humidity is trapping moisture in the paint? Happens here in Mississippi if I’m not careful.
How fast drying is it? I think I used that stuff in the past but do not remember. The faster it dries the more moisture can affect surface when it dries, as TJ suggested. Problem is that evaporating thinner or solvent cools the surface and can cool it below the dew point, causing condensation on surface. The faster the solvent evaporates, the more cooling, and the more the risk of this (conventional lacquers very susceptible to this).
I think I just observed that using this on an unpainted plastic somehow prevents certain areas from being completely glossy but I experimented on a small painted plastic and it seems to gloss well. Wonder if it just doesn’t go well with bare plastic.