More - exterior surface mold
I have been working like a fool for parts of the last couple of weeks to take a 2002 exterior that has not seen any care, with the exception of one small test someone must have done ..then walked away, likely at the size of the task. I can see a finish line about a week away. I've cleaned, and cleaned again, and gone thru three fine grits to get to the compound/wool buffer stage - only to be set back by finding more mold after bringing up gloss.
Unlike the typical boat, this surface is thinly gel-coated so the surface cannot be made perfectly flat; the matt cloth is clearly visible. And, you cannot simply pad or sand the craters.
This time I tried something that did not need a 3M pad: Peroxide. It's the same stuff I used to completely remove the water stain in the fuzzy ceiling. It's 40% sold by Sally Beauty Supply (much stronger, it will burn your skin) in a creme that does not dry so quickly.
Still, it dries, so I attempted to use Saran Wrap (like I did inside) to keep it. Fail. It's too much a chore to handle the wrap in a breeze and it did not stick to the surface very well.
But, it worked without all the @#*" labor needed to pad the whole thing. The second pic shows the before under the window sill - I left it on overnight and simply washed it off. That section is clean now.