Instructables
Picture of Polytarp Sailmaking - Crab Claw
instruc1.jpg
This instructable describes the construction of a simple sail from cheap material. The sail shown here is a "crab claw" or Oceanic lateen, which is being built for my nearly-finished proa. Anyone who has been following Tim Anderson's excellent series about canoe building might be interested in this tutorial, until Tim does a better one that is.

The techniques shown here come partly from Gary Dierking's book "Building Outrigger Sailing Canoes", and my experience building a few sails in the past.

If you have any questions, suggestions or criticisms, please comment.
 
Remove these adsRemove these ads by Signing Up

Step 1: Preparation

Materials:
- Polyethene tarp fabric. I got mine from a canvas supplier. It's 230g/m2, 2m wide and cost me about AU$7 per metre. An alternative source of new material is pre-made tarps which can be cut down, and this way you might get some usable metal rings, webbing etc. You could probably get scraps from any business that does heavy sewing, like upholsterers, sailmakers, places that do awnings and canvas work.

- Nylon webbing. This is used for reinforcements and in my sail, for lacing points. I bought it cheaply when I got the tarp but you could get old car seatbelts for nothing from a wrecker and slit them down the middle with a hot knife. Leather or heavy fabric would work too.

- Thread. I used various thread that I already had. Use the heaviest your sewing machine can handle, or whatever seems reasonable. Probably best to get this from a sailmaker or online. Make sure it's polyester.

- Stainless steel rings. I had some of these already. If you found some scrap stainless rod you could roll your own and weld the join pretty easily.

- Eyelets/grommets: I didn't use any of these, but if you do make sure they are brass or stainless steel, not brass or chrome plated steel. Steel will rust, break and make your sail ugly.

- Double sided tape: I bought some stuff intended for laying carpet. It's super sticky and great for holding things in place while you sew. I had to cut the roll widthwise with a knife as the stuff I bought was too wide.

Tools:
- Sewing Machine: Someone you know has one they don't use. Older is better generally. When you find a machine spend lots of time sewing samples of your fabric/webbing with the thread you'll use. Fiddle with upper and bobbin thread tension until it works reliably. You may need to experiement with different sized meedles too.

- Scissors: Some heavy shears and some thread nippers are a good combination, but whatever you have is fine.

- Unpicker: Just get one.

- Small, sharp knife: Use this for everything.

- Measuring devices like a tape measure and ruler

- Permanent marker.
RaptorWing1 year ago
Nice instructable. I think once I've finished my next skin on frame canoe, I'll try a crab-claw or a modification of a crab-claw on it. Do you plan on an instructable for the aka/ama?
Dr.Bill5 years ago
You from The islands?
Leon Close (author)  Dr.Bill5 years ago
No I'm from Australia, North coast NSW. This canoe is a mongrel really, it doesn't follow any existing tradditional design. It's ready to sail right now but it's raining heavily and has been for some days. The river is full of flood debris.
Your not where the fire is then. Are you?
Leon Close (author)  Dr.Bill5 years ago
You couldn't light a fire here if you tried. Flooding is more of a worry today.
Dr.Bill5 years ago
Nice Outrigger. Reminds me of home.
Leon Close (author)  Dr.Bill5 years ago
Thanks! Where is home for you?
My island is Oahu. I Palolo Boy.....