Hi Andrei, After looking at your photo, and noticing the similar stains on the antifouling paint, my thought is that it is staining from the water, if the boat was left in the water for a summer. If you look at photos of boats that have gone down the Intercoastal Waterway, they all wind up with brown stains from the water in the waterway. I would think that they will be fairly easily removable; either with a gelcoat cleaner, and if that doesn't do it, then with a hull cleaner that has some oxalic acid in it. Connie ex M15 #400 Andrei Caldararu wrote:
Dear members,
the boat I am looking at buying (1975 M-17) has a mysterious deposit just above the waterline, see the photo at
http://www.math.wisc.edu/~andreic/P6070387.JPG
Can anyone guess what it can be? The boat spent most of the last few summers (except for the last one) docked on a fresh water lake in Utah. What is very strange is that the deposit appears to exist only *above* the waterline. Do you think it could be some kind of minerals from the water (e.g., iron, calcium)? How hard would it be to remove such a deposit? Or a mold, that grows on humid gelcoat, but not in the water? Could it have damaged the gelcoat?
Despite the fact that the boat has been in storage for the last year and a half, I know from sailing pictures of the former owner that the deposit was there at the end of the last summer when the boat was sailed, two years ago (photo was of the boat in the water, sailing, and one could see the deposit at the bow).
Thanks,
Andrei.
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