Sunday, December 30, 2007

Sailmaking Weather

This is the kind of weather that slows down the boatbuilding process when you're working in an open, unheated shed. Today it's just raining, but when I took this photo Friday morning, a heavy wet fog had drifted in and soaked everything in the shed, including all the inside and outside surfaces of the hulls. This made epoxy work impossible for most of the day, but yesterday I did have a short period of decent weather and was able to work on preparing and installing stringers for the starboard floor panels. Since more of this kind of weather is likely in January, I broke out my new Sailrite sewing machine and spent much of Friday getting used to operating it by making some canvas bags. By evening I was feeling confident enough to start working on the jib kit. The machine sews flawlessly so far, easily feeding the slick Dacron cloth thanks to the walking foot feature, and making perfect zig-zag stitches with correct tension right out of the box.

The sail kit seems straightforward enough. All parts are precision cut and labeled. You simply match up the seam lines, baste the parts together with Seamstick tape, and run a double row of stitches down each side. Stitching in a straight line is similar to cutting with a jigsaw or circular saw. You just have to go slow and pay attention to what you are doing. I'm pleased with the results so far, shown below:

I started with the smaller, upper panels of the sail, as they are easier to handle and the seams are shorter. At the head of the sail is a patch assembly consisting of 5 layers of progressively bigger patches to distribute the load from the halyard. These are sewn on with the smaller patches sandwiched inside. There are other patches that will be sewn on at the tack and clew, and also at the reef line tack and clew. I decided to stick with a traditional hank-on jib with a single row of reef points as shown on the Tiki 26 sailplan. I will also make a smaller storm jib for conditions when the single reef is not enough. I don't like the complication and expense of roller furling, and from my past experience with smaller Wharram cats I know that changing headsails is not too difficult on such a stable platform, especially with the safety of the forward tramp to work on. I also plan to fit a continuous halyard that allows the jib to instantly be doused in an emergency without the need to go forward to the tramp. This is done running the halyard from the head of the sail, down the mast to the usual cleat or clutch, but instead of terminating it there, it continues forward to a turning block near the tack of the sail and up the luff to fasten at the head of the sail just like the other end. The jib can then be raised or lowered with a single line.

Here is one of the seam details showing the quality of the zig-zag stitches the Sailrite machine makes - click on the photo for a larger view. If I can keep all the seams this consistent, I will be happy with the sail. The luff and leech ends of each row of stitches will be finished off later with the folded Dacron tape that is sewn on the edges. The leech has a control line fitted inside, and the luff has a wire rope with thimbles at the tack and head that are also hand sewn to brass rings in the corners.

I'm building the sail in sub-assemblies because of the size and the limited amount of floor space I have. Here, the foot panel is being sewn onto the bottom full-sized panel. At just over 10 feet, this is the longest seam between panels. The next step will be to complete the tack and clew patches of this sub-assembly before sewing this to the next panel and then adding the top half of the sail. I'm not even bothering to keep up with my hours on this project, but so far it hasn't taken long at all. It's interesting work and gives me something to do when I can't work with epoxy. Best of all, I'm saving a substantial chunk of change that can be put into other things for the boat, and getting the sewing experience I will need for the more complicated projects such as the dodger/decktent I plan to build.


BoxerBoy said...

Those stitches rival anything that I've seen on the English dinghies that I've sailed (I'm thinking mainly of Holt sails or Jeckylls) - a tribute to your patience and competence, Scott! It was a good idea to make a few bags to get you started. They mention that in an excellent book called "This old boat" - practice on something small! Anyway, happy new year 2008 and thanks again for this excellent blog. -Chris in Paris

Scott B. Williams said...

Thanks Chris,

Getting good results with the stitching is largely a matter of having a good machine, I think. It really is nice not to have to stop and adjust the tension constantly or worry about the needle not having enough power to penetrate. The walking foot feature on the Sailrite machine is also largely responsible, as it feeds the material in flawlessly.