I finished my C16 in the end of May, and have been out about a dozen times since then. Yesterday as my wife and I were launching in the Annisquam River, she mentioned some dark spots on the deck. She pointed out what she was talking about, and sure enough, there are dark splotches on the deck which look like the shape of water droplets and have a darker hue then the rest of the mahogany. Tried to rub them off, but to no avail. I'm pretty sure they're in the glass or epoxy or (eek!) the wood itself. Now, I put 6 coats of high gloss epifanes on this boat, to a perfect coffee table finish (which is unfortunate considering all the scratches now punctuating the keel line). In addition to the spots, I am also seeing a pattern of weave when I look at the glass at the right angle. I know that I could not possibly have worn through 6 coats of varnish in 2 months, most of which have been inside my garage (where I store the boat), but is it possible that the UV protection offered by the varnish is already wearing down??
My greatest fear with the spots is that I let water spots sit on deck too long the other morning while the boat was sitting on the car, and that water magnified the sun to 'burn' spots into the wood. The odd thing about this hypothesis is that a few of the spots are visible in a cloudy area of deck where I sanded into the glass, perfectly showing the grain of the wood like there was no glass there at all.
Should I take this thing out of commission for a few weeks and lay down another 6 coats of varnish? I'm totally at peace with the scratches that rocks have imparted on the hull (it is a kayak after all, and gets a lot of use), but the water spots are really bothering me, and I'm worried that they've done irreparable damage to the deck.