Take everything out of the inside of your boat and look for some left-over plastic from the manufacturing process. I once found a couple of 1" diameter left over plastic pieces inside my Hobie loose and rattling around, I saved the scrap and have used it on several occasions to heat and fill. Once I a put a screw in the wrong place and had to fill the hole. Use a mini butane torch (be careful with this one) or soldering iron, first heat the area on the boat, stick the scrap plastic to it, melt the scrap plastic in to fuse, cut off the excess, let cool and sand off for a smooth finish. If you can't find some scrap plastic off your boat cut some off your buddies! Just Kidding, It does need to be the same poly based plastic though
