After paddling my son's shiny new Ocean Kayak, my old, often-repaired Indian River canoe felt like paddling a waterlogged door. So in the interest of chasing fish along the Florida Gulf Coast's oysters and islands, I decided to add a sail. The rules of the project were that I spend a minimal amount of money and that I use what's already around the house as much as possible (it's summer and I'm a teacher).
Traditional sailing is all about performance, but performance is a relative term. My goals were to maintain my normal paddling speed (about 2.5 mph, according to Garmin) without paddling, to keep things simple, and to not ever bail out a swamped canoe.
I did some sailing when I was young, so I sort of knew what to do, and I had some old sailing odds and ends in the attic, but everything I added could be made with materials from the hardware store.
Sailing is all about the balance between the sail's center of effort and the boat's lateral resistance (imagine holding a sign at a windy protest rally - if the stick is in the center of the sign, it's balanced, if it's off to one side, the sign wants to swing downwind like a weathervane). More pressure in front of the leeboards=swing downwind, more pressure behind=swing upwind, so all the rigging needs to be as adjustable as possible for the first few attempts. I ordered the steps by how difficult they would be to change.
1. mast placement
2. sail rig
4. a way to steer (technically you can steer with the COE/LR balance but the COE changes as the wind speed changes - grrr)
Many thanks to Tim Anderson and thousands of other online canoe sailors and boat tinkerers!
Step 1: Mast Placement
Step 2: The Sail Rig
The original sail had a sleeve for the mast, which is simple and efficient, but I felt like I ought to be able to power-down in a hurry, so I replaced the luff edge with brass grommets and rope hoops and attached a halyard pulley to the top of the mast. I also ran the other end of the halyard down from the sail head so I can pull the sail down rather than count on graviity. I sealed the inside of the mast with spray foam, just in case.
The boom is a section of wooden closet rod from the hardware store that used to be my push pole. I attached a cut-away piece of PVC at the mast end so the boom snaps onto the mast but still slides up and down.
Step 3: Leeboards
I made mine out of scrap 1/4 in. plywood, which is thinner than typical, but I'm hoping that because they are pressured against the hull when in use, they'll be stiff enough. Length was also a guess. I felt like there should be a little more than two feet under the water, but if I'm wrong, they're easy to replace. There are many, many shapes of leeboards to choose from. I took this shape from Leeboards.com's pictures of Danish sailboats because I though they looked cool. The top circle/bottom circle ratio, as well as the length/width ratio are also 1:1.6-ish
The thwart that holds them is scrap 1 in. sch 40 PVC. I screwed a 1/2 in bolt through a couple of PVC plugs and cemented them with J.B. Weld, then measured the Thwart for the widest part of the boat and glued-in the plugs. I'm securing this in place with straps until I'm comfortable with a permanent position. From just looking and guessing about the COE, I have their position narrowed down to within a foot, but we'll see.
The leeboards can be raised and lowered with lines that lead past my seat. They are attached to the opposite edges of the boards from the direction they pull, so they help hold the board higher when not in use.
Step 4: Rudder/steering Oar
Have fun and be safe!