I visited one of our local textile merchants, and while talking to the seller, who knew his boats far better than I do mine, we narrowed down to a tanbark cotton, that had become slightly discoloured during manufacture, thus was on sale.

He had used it for sail covers and canopies, and had found it easy to sew, even if it was fairly thick. Soft, but slightly heavy, it proved much easier to handle than a light ripstop fabric. A junk sail need to have some weight, to fold properly when you lower the yard, so if you’re using ripstop your sail might end up a bit too light, putting a lot of stress on downhauls and battens. Real junk sails can sometimes do without batten downhauls due to their weight, but my battens proved too flexible for normal downhauls.

As it is now, not even twenty years of use will make it brittle, thus just what I wanted. I don’t want to sew new sails if I don’t actually have to. I might change my mind one day about the size of the one we’ve got, say by adding a bottom panel, but not just now :-).

Using a heavy fabric like that would be lunacy if the sail was big, but ours would just be a few square yards in total. Indeed, the fabric was so easy to handle that I made a number of bags out of the same material.

A junk sail is a Chinese variant of a balanced lug sail, and has a yard at the top, a boom at the bottom, and a few battens in between. Classic junk sails were made like this: the yard, battens and boom were placed on the ground and connected with a thick rope that was staked to the ground. This rope often ran round the sail’s entire perimeter. The battens, the yard and the boom were then secured to the rope by various means. Then panel after panel of fabric was added, sometimes vertically, sometimes running between the more or less horizontal battens and the yard/boom.

Then the parrels were added, small pieces of rope that hold the battens, yard and boom close to the mast, and then additioanl parrels that move the sail sideways. A junk sail, when you’re tacking, is carried almost like a battened Bermuda main sail, while downwind it is almost carried like a square sail. The parrels involved are called boom hauling parrel, yard hauling parrel, etcetera. A downhaul from the boom is essential, and quite often there is a downhaul attached to each batten – unless the battens are very bendy, in which case these downhauls don’t do much good.

For my yard I combined bits of the Klepper boom and the gunter yard till it was about 74” (1.88m) long. With hemmed edges my fabric is about 67” (1.7 m) wide, and the sail’s width decreases after the top batten, in modern junk rig fashion.

The battens are 350 mm apart, so there are three identical panels, while the top panel is approximately triangular.

As my battens are made from flexible aluminium, the batten downhauls didn’t work at all. Instead I have now one slab reef, making a bundle of the two lowest panels, by just tugging on a single line, without leaving the seat. Hope this proves to work as well in practice, as it does on land :-).

Mixing stiff battens with flat fabric makes the sail less powerful than what it could be, so the norm is becoming stiff battens and ‘baggy’ panels, or flat panels, with hinged, or bendy, battens. Some add Gurney flaps to their junks sails, and they work very well on stiff, flat sails.

I hate glassfibre battens, for various reasons, so I decided to use aluminium, as I have a good supplier nearby. For boom and yard we used aluminium as well. The yard (top boom), as I’ve already mentioned, is made from reused Klepper parts, while the boom is two rectangular aluminium tubes, bolted together. The sail’s leading edge (luff) is reinforced by a reused bit of jib sheet (very thick), and the rear edge (leech) is reinforced by a slightly thinner rope, our old spinnaker halyard.

To make the batten pockets proved easy, when you’ve done the first by a more cumbersome method. The way to do it is to first make the pocket from a folded over 2” cotton band, with reinforced ends, then sew it in place. So the batten runs in the pocket, not between the pocket and the sail proper. If they wear out they’ll easily be replaced.

All edges are folded over and ropes are run in them, except along the boom that is simply clamped over the folded over fabric. Inside the vertical folds is a black 2” band, the kind used by kite builders, so running the ropes into the folds was very easy, as the silk-smooth surface of the black band was very slippery; an unforseen bonus.

The junk sail is over-engineered, and will withstand any hurricane, I’m sure, far more than the crew will withstand.

End of part one.

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