Materials, part 3: Sailcloth

Dreaming of this boat building project over the last few months, I've largely forgotten that it is a sailboat, and will eventually require a sail.  The Bolger Teal I'm building with my brother has caused the same sort of amnesia.  I guess one gets so caught up in making the hull that it's hard to remember all the other pieces required to make it move when the wind blows.

Luckily, the Melanesia plans come with a detailed description of the crabclaw rig, how to trim it for performance in various winds and on various points of sail.  They also describe how to sew together the sails with a simple technique that actually seems achievable, despite my complete helplessness with cloth.  So I've been thinking about the sail materials before I've even begun lofting the hull panels.  Quite a turnaround!

A crabclaw polytarp sail  in action

on a different outrigger canoe design

I've read about people cutting their sails from inexpensive plastic tarps.  It's certainly an option, and one Mr. Wharram endorses, though he warns that such sails deteriorate rapidly from UV exposure.  But it would cost only about $10 to make a sail from a tarp, and that option will remain on the table until I get a sense of the budget.

Another option would be to use Tyvek, a sort of plasticized paper that is commonly used as a semi-permeable house wrap in the USA.  If the name doesn't instantly conjure up memories of the Tyvek logo plastered all over a new home, you may recognize it as the stuff of FedEx envelopes or disposable painter's suits.  From what I've learned reading other cheapskates' sailing stories, it is lighter than polytarp, performs better in light air, and lasts a bit longer.  It's available in 3' x 100' rolls - enough to make ten or fifteen sails - for under $30, or I might be able to score a partial role from a construction site dumpster for free.

And then there's the "real" sailcloth option.  I happen to be within an hour's bike ride of Rockywoods Fabrics, who stock a large variety of outdoor fabrics for camping/backpacking DIY'ers.   I looked up specs on a replacement sail for my El Toro, and found that it was made from a 3.5oz polyester fabric.  (Polyester apparently stretches less than nylon, and so makes longer-lasting sails.)  Rockywoods sells a white 4.5oz coated ripstop polyester fabric for $5.09 per linear "yard." (At 5' of width, a "yard" of this fabric is considerably more than a square yard.)  It appears that I would need about 5-10 of these yards to make the sail; at $5 per yard, this makes  a real sail cost-competitive with buying a roll of Tyvek and only 3-4 times as expensive as polytarp, while lasting much longer.  Rockywoods sells online, in case you're looking into sails for your small boat & like the sound of that fabric.

As I said earlier, I'm postponing this decision until I see what I can afford.  But if at all possible, I think I'll go with the polyester fabric option.  It seems much more of a "real" result, and it's only slightly more expensive than the cheaper materials.