More like a bad batch of gray matter.Maybe you got a bad batch of lexan?
Not worried, so far I have found that a combination of very fine sandpaper and my assortment of plastic polishes can do what's needed to remove (or sufficiently thin down) the Future.Actually it cannot in this case. I have to apologize if I sent you down this course. I now remember that I considered applying Future to the fins on my "Color the Sun" Crayon rocket, but I did not. This is because of the cleaning issue. You cannot apply ammonia (dissolving agent for Future) to Lexan as it, like Future, is an acrylic and it will be weakened. See: https://www.acplasticsinc.com/informationcenter/r/polycarbonate-sheets-cleaning-care. At this point, it may be better to start all over.
I just need to figure out a reliable process to get these fins looking the way I want. This is getting tiring.