Bear Paw Sail

1. an account of a sail shaped like a bear's paw
2. a method for sailing downwind with a boomless sprit sail
3. a light daggerboard case and sprit for camping

click to enlargeHere is a sail which is really a kite. It sits on the top of a short mast where it is free to rotate and twist. It is controlled by a downhaul attached to the front and by a continuous main sheet attached to the two sides near the back. The boat in the photo is not really sailing. It is just being blown sideways in front of the camera. The breeze is coming from the left. The white office building hiding in the trees opposite is the headquarters of Canada's notorious tax bandit bureaucrats (Canada Customs and Revenue Agency). I suspect they have someone on the roof scanning the water for boats that don't gibe with reported incomes.

click to enlargeTwo sails have been rigged on the boat at the same time to show their relative size and location. The blue canvas sail is a 5x4.5 boomless sprit sail with a mast sleeve. The beige nylon sail is a 5x4.5 polynesian crab claw sail which looks more like a bear's paw than a crab's claw. We don't have any crabs in the woods of Ontario where I imagined using the sail on camping trips. But we do have bears. Both sails are cut from standard 5ft wide fabric store cloth. The mast for the blue sail is right at the bow. The mast for the beige sail is at the front thwart and puts the front of the sail right at the bow. Both of these sails are located so the boat can be sailed with the existing daggerboard and no rudder. Both are well balanced fore-and-aft.

click to enlargeThe bearpaw sail is a nylon bag made to fit over two bent fibreglass tent poles. The idea is to carry the sail on a camping trip without having to carry a long mast and sprit. And to use the tent poles to avoid carrying extra weight. Since a sail and a tent are not needed at the same time on a camping trip it should be operationally feasible. The mast is just long enough to let the sail be drawn in close hauled without hitting the side of the boat. The sail was made last winter. As soon as it was tried on the water it became abundantly clear that if tent poles are flexible enough to bend in a semicircle at the front of the sail then they will also bend at the back of the sail. As soon as the wind filled the sail it became baggy at the back and lost much of its power. The solution so far was to cut one 1/4" plywood batten for each side, put loop of wire in the ends, and slip them over the tent poles where they are not supposed to bend. A big improvement but not ideal. In the photo there are bricks holding the flexible tent poles in at the sides. The 8 ft 2x2 stud was put in the photo to show the scale but it got cut out of the photo at one end. Note the unfair kink in the curve of one of the tent poles at the top right. That is the repair described below.

click to enlargeOn the left is the mast with its loop at the top for the sail to twist and turn on. Two holes were drilled through the mast so the loop would not drop down one side with the weight of the sail. Not apparent in the photo is a thin hole through the mast just under where the partners go. A piece of stiff wire (a bicycle spoke) goes through the mast to keep it from lifting out of the boat. The sail is, after all, a kite and tries to leave the boat vertically under some conditions. Next to the mast is the, um, yard or boom or whatever its called. A loop of string in a hole on each end ties it to the sail. The end does not need to be notched as shown. The notch is left over from another method I tried of attaching the sail. Two blocks have been screwed on at the middle to keep the loop on the mast from moving off centre. Top centre in the photo is the mast "partners" that I've been using while testing the sail. It screws onto the thwart on the boat. This is the third "partners". The other two were of thinner plywood. They broke when the boat capsized. The mast step is the usual wooden block with a hole in it. The hole is odd shaped because the mast is a piece of stairwell handrail. A previous mast step of lighter construction broke when the boat capsized. On the right are the two plywood battens which keep the back of the sail from bending.

Across the centre of the photo is one of the fibreglass tent poles showing a repair. The metal tubing at the end of one of the sections split along a seam. It was repaired by winding wire around the end and embedding it in epoxy adhesive. The fibreglass on the adjoining section also split. That was repaired by winding polyester twine around and embedding it in epoxy adhesive. The repair is far from perfect. I asked about tent poles on the rec.camping newsgroup. There are better quality fibreglass tent poles. On some expensive tents flexible aluminum poles are used. To discourage more splits a bead of epoxy adhesive was run along the seam of each metal tube on the tent poles. There have been no more splits.

click to enlargeI'm not sure this bearpaw sail is practical for camping trips, but it sure is fun trying to learn how to sail with a kite. In Polynesia the ocean winds are steady and the downhaul at the front of the sail is set and cleated off. On the small waters where I sail the wind is never steady so the downhaul is wrapped once around the mast and cleated temporarily in the teeth, under a foot, or held in one hand. It takes two hands to work the mainsheet, pulling in on one side and easing out on the other. In the light winds where I dare use the sail it seems to work best at about a 45 deg angle to horizontal as in the photo. When the wind picks up the boat heels but the sail does not twist off and spill wind like a sail laced to the mast does. The bearpaw sail just lifts one side and draws stronger than before which accounts for the capsizing. I have not capsized this boat with the blue sprit sail. I have been out with the blue sail in winds so strong that I could not paddle into the wind. Its quite amazing. I lie down as low in the boat as possible and give it its head. Such a small boat surging along in such strong winds. The blue foam sponsons help, of course.

click to enlargeBut the centre of effort on the bearpaw sail is high, the rig is heavy, and its sailing characteristics too unfamiliar and powerful to go out in any but the lightest winds. Polynesian crab claw sails are estimated to be up to 40% more powerful on a beam reach than other kinds of sails. I believe it. To reef a crab claw sail the sides are pulled together making the sail loose and baggy. I do not dare pull the tent pole sides together as the poles might break. To reef the bear paw sail I pull the pin, lift the mast up out of the step and partners, and toss it overboard where it floats on the surface until the wind calms down. Next season I plan to move the bearpaw sail to a bigger boat, the Dogskiff, that can cope with its power. I've already tried the sail on the Dogskiff but the mast must be moved aft to balance the sail fore-and-aft. If anyone is interested in trying such a sail I'd recommend tying off any rudder amidships to have both hands free to work the lines. I'd suggest flexible plastic electrical conduit for the bent front and broomsticks for the straight sides of the sail.

For more information on crab claw sails look at The prototype for my sail is the John Rowland drawing at the bottom of this page . David Beede's experimental polytarp sail based on the Rowland drawing can be seen at simplicityboats. The boat used with the bearpaw sail is the Loonie which appeared in Duckworks last year. A building plan and description can be found on this website.

click to enlargeWhen I first started sailing with the blue canvas sprit sail, every time we got hit by a gust downwind the boat would do a snap 90 deg turn to the side. Try as I might I could not muscle the little boat back on course in the gust. The best I could do was force the boat to go downwind sideways. The phenominum is called broaching. It's quite a problem with small sailboats. One day I discovered I could control the boat downwind by letting the sail fly out in front. One photo shows the boat sailing close hauled toward an open dam. The other photo shows the boat running down wind away from the dam. The sail has done a 180. The sprit is out in front of the boat. The bottom of the sail is pulled back into a pocket or bag. It's much easier to control the sail that way than straight out to the side in the normal downwind position. You can only get a bag like that on a boomless sprit sail with a rotating mast. I can avoid both broaching and the dreaded dead man's roll with the sail in that position. And I can avoid power gybing by reaching forward and passing the whole mainsheet around the front of the mast. I've used the technique on a larger boomless sprit sail on my Dogskiff. On that boat I've come down river on a windy day between high banks which compressed the wind like a wind tunnel. It was an exciting controlled sleigh ride with the sprit sail bagged out front like a spinnaker. This downwind technique must have been known previously to others but in all my reading I've not come across it.

click to enlargeLast winter a small daggerboard case was made for the narrow paddling and sailing Dogskiff. The Dogskiff and the Loonie share the same daggerboard. I wanted the daggerboard case to add as little weight as possible to the hull which has to be picked up and carried over portages, and lifted on and off the roof of a car. I was delighted when it only added 2 pounds to the hull. Another goal was to keep the daggerboard case out of the way when paddling and when sleeping on the boat under its homemade tent. The boat is paddled transom first for speed and directional stability. That puts the daggerboard slot on the high side of the heeled boat opposite a right hand paddler and clear of the water. Water splashes up the case into the boat when paddling in a chop. I plan to make a plug for the top to block the water. The case is braced low to the side where it doesn't flex the thin plywood.

click to enlargeIts the usual construction for a daggerboard case. Some daggerboards go in at an angle like this one. Some are installed straight up and down. These two photos are included for anyone who has not made a daggerboard case and would like to see how one goes together. This one was made of cheap, light lauan underlayment plywood which many boatbuilders would not use, and light red cedar wood. click to enlargeThe interior of the case was given two thin coats of polyester resin and two coats of polyurethane varnish for abrasion and water protection. The edges of the plywood were sealed with two coats of polyester. The rest of the case got two coats of linseed oil which will be renewed each spring along with the rest of the interior of the boat. The glue used was PL Premium construction adhesive. The glue lines at the slot in the hull were sealed with two coats of epoxy adhesive.

click to enlargeThe purpose of this sectional sprit was to replace a 12 ft pole sprit with something shorter and lighter for camping. Three tubular steel handles from discarded brooms did the trick. The 3 ft ruler in the photo shows the scale. At the lower left pieces of dowel wrapped in sheet aluminum cut from soft drink cans were glued with epoxy into the ends of two tubes to provide something for the open ends of the middle tube to fit over. The open ends were reinforced by gluing collars on them which do not show up in the photo, cut from the tube and split open to fit. Foam rod insulation was shoved inside so the sections would float if any fell overboard. Barely visible in the upper right, the ends of the broom handles had ready made holes for tying the mast and sail to the sprit. The sprit was painted white, unfortunately causing the photo to be overexposed. A couple of photos taken during construction were lost when the film was in a capsize of the Loonie while trying out the bearpaw sail.

click to enlargeIt was a cool and windy fall day on a crystal clear northern lake when the new daggerboard and sectional sprit were tested together. Both performed above expectation. A canoeist discouraged by the high wind went home after a short paddle. Before the photo was taken the boat had been slipping through whitecaps and gliding over streaming foam with ease. The daggerboard case is so fortuitously placed that the boat can be steered by raising and lowering the board. If the board is raised 3/4 way the boat rounds up into the wind and tacks.

The photo shows a blue sports bag used as a back rest when sailing from a reclining position. The bag is stuffed with gear and clipped to lines through holes just under the gunwales aft of the daggerboard as seen in the photo. I made the mistake of sailing in a strong wind without back support early in the season, pulled a muscle, and could hardly walk for two weeks.

The modified nylon canoe and kayak sail from TF Jones "Boats To Go" is in its fourth season. The double layer of fabric store nylon is stretched and baggy and showing its age, but still moves the boat along at a good clip. The hull is in its third season. It is better now than when first built. I think its finally the way I want for paddle and sail camping. There is more information on the history of the Dogskiff in files at

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