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Fitting a junk rig to a Klepper kayak - Part 2

The sail can be made of just about any cloth or plastic. The sail shown in the picture on the previous page is cut from a discarded surf-board sail. I must find a more modern discarded sail of the transparent plastic type for the bottom panel. At the moment I have to lift the boom by hand to see the oil tankers heading towards me.

The battens are of bamboo. They are pushed into sleeves which are closed at the mast end. The sleeves are longer than the width of the sail (see the photo on page 1). They are folded over the end of the bamboo rods at the outer end, with a tight lashing to hold the rod in. There are holes at two places in each sleeve, to attach the loop of rope that holds the batten to the mast.

Sail plan and mast

The sail plan and the dimensions of the three part mast. The side keel is drawn above the sail. These dimensions are for the Aerius 2000, the smallest Klepper kayak, and need to be scaled up for the bigger boats in the range. Click on the picture for a larger view.

The mast is threaded through between the battens and the rope loops. The loops need to be this wide so that the sail can be furled and then folded up against the mast without unthreading it.

The mast

The mast is made from three sections cut from three masts from surf sails. The shortest bit sticks through the mast hole in the Klepper cockpit and into the foot hole, with about 20 cm sticking up above the cockpit rail. There is a collar mounted permanently on the mast stump just above the cockpit hole. The next section of mast slides down the stump and rests on this collar. The upper mast slides onto this middle section, with a smooth join that the sail battens and loops slide over. The dimensions are such that the upper mast can also slide directly onto the stump. In this way the mast can be reefed at the same time as the sail. This makes unnecessary the rope for hauling the top of the sail tight against the mast, which is a normal part of the junk rig.

All the mast segments and the rolled sail can be stowed in the boat, or behind the cockpit, and assembled at sea. First the stump is stuck down through the hole in the front of the cockpit, then the middle bit is threaded through the spaces between the sail battens and the cords. The halyard is threaded through the pulley at the top of the third mast section and this section is then pushed onto the middle section. Finally the mast is swung into the air and the middle section is slid onto the stump. The string dangling from the bottom of the sail is made fast to the collar on the mast stump. The sail is now pulled up with the halyard, which is made fast to a cleat on the bottom of the boat. This halyard tension holds all the pieces together, so it must not be made fast on the mast itself. There are no stays for the mast. The junk rig is a very low stress system, both mechanically and mentally.

The halyard must be held by a quick release cleat. In squally weather one must be able to drop the sail quickly.

The sheet, a single line, is connected near the end of the boom, which is a piece of bamboo just like the other battens.

The side keel

There is only one side keel. It is an oval piece of plywood, made from several pieces of plywood to give an aerofoil shape, so that it tends to press against the softly padded side of the Klepper, which , for those unacquainted with this ancient and ingenious design, has a narrow air bag to tighten the skin against the frame. I have no idea if the aerofoil shape works, but it makes a good talking point with engineers. The keel has two holes, filled with a single piece of rope, or two, which together hold the keel upright in the water. This is better shown than described:

Detail of keel mounting

The side keel is held at three points: It rests against the side of the boat. One rope is taken from the top to a suitable point within the cockpit. A second rope, or an extension of the first rope, is taken from a hole lower in the keel and fastened to the mast. By adjusting the ropes, the fore and aft position of the keel, and its tilt in the water can be controlled. To sail on the other tack, the keel is taken up and flipped over to the other side of the boat. Click for a closer view.

This arrangement is not the best way to turn a boat without it making leeway, but one does not do it very often, because the Klepper is simply not good at turning, whatever keel arrangement one uses.

How well does it sail?

What do you expect me to say? Wonderfully, of course. It is surprisingly unworrying, even for a nervous sailor like me. The sail steadies the Klepper, which, when lightly loaded does feel a bit tippy. The shallowly sloping sides of the hull give a quickly increasing stability as the craft tilts, so the sailor does not need to do any athletic leaning over the water from an uncomfortable position on the cockpit coaming. The sail described here is too small for efficient pushing in light airs. The junk sail is not renowned for light wind performance. The reefed sail seems quite safe in any wind that will not flood the boat with breaking waves. The rig can be mounted with a cockpit cover in place, but the side keel is then difficult to use.

I have, however, tested the boat to the limit before committing myself to publishing my adaptation of this ancient rig. It was the competitive instinct that a sixty five year old like me should have been able to control, that got me into deep water. There were these two slinky four oared skiffs overtaking me, as they easily do overtake even a superstar kayak paddler. There was a brisk breeze, gusting off the uneven contours of the coastline. A spirited squall materialised. I could just pass between the rowboats, which were directly downwind. That was the trouble. As I mentioned earlier, the sheet is only a single string, instead of the multiple sheet that keeps the proper junk rig flat. The sail twisted so that the sideways pressure on the mast suddenly changed direction.

As my green sunhat and grey beard emerged from under the water one of the ladies in the row boats said: "Poor old Ernest Hemingway". But they waited kindly until I had scrambled aboard the waterlogged Klepper.

This event showed the real charm of the junk rig. In a few minutes I had got the sail reefed and up again, on the reefed mast. We wallowed along, far behind the rowboats, but still faster than I can paddle. I baled with one hand, which would certainly have slowed my progress if paddling, until we reached harbour, almost dry.

My next improvement will be a proper de-watering system.

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