Speedwell´s Junk Rig
When I left South Africa in March 2002, Speedwell was rigged as a Bermudan sloop with roller furling jib. Later that year I was given the opportunity of sailing from Cabedelo on the north east coast of Brazil to Cape Horn and back with Pete Hill on his junk rigged catamaran, China Moon. I was so impressed by the advantages of the rig that a year later, while I was waiting out a hurricane season in Trinidad, I decided to convert Speedwell’s rig to junk. The change was a happy one for me and one wonders why the rig is so rarely seen. Out of the many hundreds of cruising boats I’ve encountered on my travels I don’t recall more than five or six junk rigs.
I don’t claim to be a technical expert regarding junk rig, but thought it might be an idea to describe Speedwell’s rig and the conversion as encouragement to anyone just interested or maybe thinking of giving it a try.
First let me list the advantages as I see them:
• Probably most important to me is the ease of reefing. Quickly done from the cockpit with no need to venture out on deck. The halyard is simply let off to lower as many panels as required, followed by a quick adjustment of the sheet and pulling up the yard hauling parrel. In an emergency the entire sail can be dropped in seconds.
• Likewise, undoing a reef is just as easy although obviously a bit more muscle is needed for raising rather than lowering. When frequent sail adjustments are necessary this can mean the difference between being lazy and just leaving the sail reefed down or making more efficient use of the gear.
• The unstayed mast means no expensive and vulnerable standing rigging.
• The sail can be cheaply and easily made by oneself.
• Stresses on the sail are spread along the battens and a hole or tear in the sail is not normally a disaster. If there is a really big tear the adjoining battens can be lashed together so all is not lost.
• Superb downwind performance with no need for a spinnaker pole to hold the sail out.
• No extra sails taking up valuable space below.
• When something breaks, repairs can usually be made with the sort of odds and ends normally carried on a cruising boat.
• Tacking is a simple matter of moving the tiller over. No need to touch the sheets.
• It’s beautiful and fun.
Sail Design
When planning the rig I decided to follow the example of Vincent Reddish who had successfully converted his Vertue to junk rig and used a low aspect ratio fan shaped sail. Slightly more difficult to cut and sew than the straight up and down Hasler-McLeod design. All the battens are the same length but they are set at varying angles. A detailed description can be found at Junk Tutorial
I liked the idea of a low aspect ratio sail and its concomitant short, sturdy mast.
The Conversion
The most daunting part of the job was replacing the deck-stepped aluminium mast. The new mast would have to be positioned on the foredeck ahead of the forward hatch and securely planted on the keel. I emailed Pete, who was then in Cape Town after a single-handed voyage to the Antarctic on China Moon, asking for advice. He replied enthusiastically and, to my astonishment and delight, offered to build the mast for me in Cape Town and ship it over to Chaguaramas on the deck of China Moon.
Dan in Velddrif donated some salvaged Honduras mahogany and one fine day in November, China Moon arrived in Chaguaramas, Trinidad and tied up alongside a handy floating barge which allowed Pete and me to offload the new mast and carry it proudly on our shoulders to where Speedwell was waiting on the hard at IMS boatyard.
The mast had been constructed with a hollow square section, tapering towards the top and covered with a layer of fibreglass and epoxy. The plan was to mount it in a tabernacle which still needed to be made to measure from wood that Pete had brought with him.
No sooner said than done. A crane was hired to remove the old mast. I patched up the deck where the mast had been stepped and it soon seemed never to have existed. Below decks we cleared the forepeak and a firm base was prepared for the tabernacle. The tabernacle itself was massively solid and also totally encapsulated in fibreglass and epoxy. A rectangular hole was cut in the foredeck and proved to be a perfect fit for the tabernacle. According to Pete, this was not to be put down entirely to good luck.
A generous epoxy fillet covered with glass fibre tape, sealed the joint between the tabernacle and the deck and has remained perfectly secure and watertight. Some strengthening bits of wood were put in below the deck ahead of it and four beautiful laminated teak knees added to the reinforcement.
The base of the tabernacle was cut away a little on the starboard side to allow easier access forward.
It was time to start thinking about the sail. The boatyard cafeteria was being renovated and I was able to use the roofed terrace as a ‘sail loft’. Open on one side to the daily afternoon downpour and intermittent workmen’s muddy boots. I worked seated on the floor with a domestic sewing machine. The panels were joined horizontally with an overlapping seam wide enough to form a long pocket for each batten. Strengthening patches and tape loops were sewn on where required for lashing the sail to the battens. Bolt ropes were attached at head and foot for the yard and boom.
I used bright yellow PVC cloth for the sail and it lasted really well for nearly 6 years and many thousands of sea miles.
I have tried to keep the lines as simple as possible. See diagram.
1. The main halyard has a 4-part purchase and makes the heavy sail easy to raise, only needing the winch for the last little bit.
2. The yard hauling parrel.
3. Spare halyard used as a flag halyard.
4. Parrels holding each batten to the mast.
5. Luff parrels connecting pairs of battens round the mast.
6. Mast lift (not shown) holds the sail bundle close in to the mast when reefed.
7. Tack line to stop the sail from creeping up the mast.
8. A webbing strop prevents the boom from moving too far forward.
9. Lots of padding to reduce banging against the mast and general chafe.
10. Sheetlets between aft ends of battens. Tied on with clove hitch and stopper knot.
11. Single sheet running through blocks at each sheetlet.
Lazy jacks are fixed either side of the sail. Fastened off at the boom with cleats.
Up to now I haven’t needed to fit a downhaul as the sail drops easily enough under it’s own weight. Sometimes it is necessary to luff up a little if the wind is holding the sail too firmly against the mast.
My first sail was cut perfectly flat. The only shape being formed by the slight bend of the battens and some twist to the sail as wind spilled out the top. Windward performance was a bit disappointing.
I experimented unsuccessfully with jointed battens which improved performance but had a nasty tendency to come adrift when the weather got rough.
Back to rigid battens. Originally they were made of oregon pine but after a number of breakages I switched to aluminium tubing strengthened with a few longitudinal wraps of uni-directional carbon fibre.
when the PVC sail needed to be replaced after nearly 7 years, I made a new sail using acrylic cloth and put some shape into each panel using the shelf foot method. My design was a bit of a thumb-suck and the sail looked a bit droopy with rather a lot of bagginess in the panels but the windward performance improved quite dramatically. However, I found that due to the obviously different distribution of stresses while sailing, the fastenings at either end of the battens which keep the sail attached, were constantly wearing through. Something that had never happened with the old flat sail. I found it quite difficult to fix this problem while sailing offshore in strong weather as the sail, no longer restrained by the end attachment, would creep along the batten and it had to be hauled back before the lashing could be replaced. I was using exactly the same thin line as I had used on the original sail.
I was also not very happy about the droopy appearance of the sail. I had read many accounts of how this might be improved with various ingenious arrangements of parrels, outhauls, downhauls, etc. but was loath to complicate things to this extent. After sailing from Buenos Aires to Guyana on the north coast of South America, I had had enough and was fortunate to be able borrow a sewing machine and be offered a place to remake the sail, removing the extra cloth. The next passage from Guyana to Trinidad was mainly downwind and the newly flattened sail gave me no problems. I described this in more detail in the post Back to the basic junk sail.
Recently I found myself back in Chesapeake Bay with an opportunity to use a professional sail loft and so made a brand new sail, using Sunbrella in my favourite yellow and as flat as a pancake. I wrote about this in A new sail for Speedwell. Possibly due to the more accurate measuring and stitching that I was able to achieve given the ideal workplace, the sail performs surprisingly well to windward and is, of course, quite spectacular downwind. I am hoping to sail to the Azores next year and feel confident that the flat junk sail is the better option.