Monday, April 26, 2010
Sunday 17 April 2010: Following the method shown in the skinboats school videos, I roll out the cloth -- 8 oz. polyester from George Dyson -- and sew a small pocket on the bow. Then I unhook this pocket from the bow, walk to the stern and pull the cloth back about 3 inches and sew a pocket there. This is where the trouble starts. I should note that skinboats school uses nylon rather than polyester in the very helpful videos they provide. I'm guessing that their nylon is a little more stretchy than the polyester that I am using. Also this polyester is very loosely-woven. It doesn't take much to open up large pull-holes in the cloth if stitches are subjected to any tension. So I pulled and pulled and opened up ugly holes and backed off and restitched and pulled and there may have been some foul language involved. In fact, I'm certain there was substantial amount of foul language involved. But so far, no cannibalism -- that was right out. Throughout this frustrating beginning, I was coming to understand the nature of this cloth that I have, and decided that a better approach would be to only make things as tight as can be pulled without opening substantial holes. I managed to get the cloth tight enough end-to-end that there are no obvious wrinkles across the hull.
So Monday I rolled the boat right-side up, and started the center seam from the cockpit, forward to the bow. Again, where the skinboat videos demonstrate better ability to pull transverse tension in the center seam to make it nice and tight, too much tension in this fabric opens holes. I manage to find a compromise where enough tension is pulled to result in a reasonably wrinkle-free skin, while keeping the pull-holes manageable. So the skin goes on with little-to-no obvious wrinkles, but it is not as tight as might be possible with a more tightly woven fabric. An advantage to polyester, is that it can be permanently shrunk in the end using an iron or heat gun. So hopefully, it is not necessary to worry so much about getting it quite as tight during the initial stitching. I'll have a better feel for how that works when this is finished:)
Over the next few evenings, I stitch up the stern and then use a blind stitch to roll the excess cloth at the seam over into a tube:
Basic stitching is mostly done. I also steam bent one last thin strip of ash around the cockpit coaming lip to build it up to be wide enough to provide a good hold for a spray skirt. I've put some last little smoodges of wood-flour thickened epoxy into some gaps here and there between the various strips that make up the cockpit coaming lip. It only needs to cure overnight, some finish sanding and stitch holes drilled before it will be ready to sew into the skin.
I've also accumulated the materials to make float bags and ordered 2 gallons of water-based exterior polyurethane coating to waterproof the skin. That will be a bit of an experiment about which more later.