Battens on a junk rig are a really big deal. Unlike the somewhat flexible strips found in most Western rigs, junk rig battens are stiff, and more substantial in terms of both size and weight. They hold the sail down when it is reefed, generally without any ties at all, and support the sail in much the same way as in fully battened Western sails, but more stiffly. They are versatile, so that if a batten breaks, or a sail panel tears, neighboring battens can be lashed together for continued sailing under reduced canvas. Having all these jobs and capabilities, it comes as not such a surprise that making junk rig battens can be a bit of a job.
First off, I want to say that it doesn’t have to be this hard. Two pieces of bamboo, lashed together with overlapping narrow ends, can be wired to a sail right through the fabric. And the sail doesn’t have to be complicated either – it can be cut out of a tarp off the shelf at the local discount store, and still sail around the circumference of the British Isles. Vincent Reddish did that, and was quite happy with the results. Still, there’s something to be said for the more involved version, taking after suggestions found in the book Practical Junk Rig.
Sails from the sailmaker just sort of happened, after much thought of tarps and whatnot. Any part of this effort that doesn’t have to involve Suzanne and Theo doing more stuff is a great thing. And now we have really nice sails. To go with those sails, battens that won’t tear them up make sense. That means no rough batten ends, and no splitting bamboo. Furthermore, the entire point of the junk rig is to make sailing easier. Equipment in need of repair 50 miles offshore in a howling wind is not an example of fulfilling that goal! So it’s sturdy aluminum battens, with nice rounded plugs in the ends, with grooves in the plugs to catch the little lines that stretch the sail out taut along the battens, and hold the battens in place. When Stuart, of Dabbler Sails, makes other traditional small craft sails, he makes regular batten pockets with grommets as shown in the photo farther down, one grommet on the edge of the sail, and one on the end of the pocket. That sounded good when he suggested it, so that’s what we have. I think it’ll be very workable.
Another word about the plugs. I looked all over on the Internet for something basic along the lines of a rounded plastic end plug that would fit this aluminum tubing. My Internet skills could be better – I’m sure they’re out there somewhere. Fortunately, among Theo’s very many skills, she is experienced with woodworking using a lathe. Which she has in her shop. Next thing you know, here we are with beautifully turned wooden plugs, just right for the job. The grooves went in by hand, and then they all marched off to the paint shop.
Now the plugs have been caulked into most of the tube ends, first one end, and then some care to make sure that the ones in the other end go in aligned with the first ones. The funny thing was that yesterday, when we did the second ends on the mizzen battens, after they were done we left them outside on their sawhorses for the caulk to set. The sun was quite warm, and when Suzanne went out later, one of them had been popped out a quarter of an inch – a solar powered popgun! Fortunately it squished right back in, with no problem. We are refraining from drilling holes in the tubing, so they won’t get any water in them – we’ll see how the airtight situation works out over time.
Some folks dispense with plugs entirely, using a machine screw through each end of the batten and a grommet in the appropriate spots in the sail, to hold the sail and batten in place. The trade-off is not being able to adjust for stretch, and potential harsh bits to do with the screws or open ends. I’m also rather fond of the idea of keeping water out of the middles of the battens. So for all the many reasons, we have gone ahead with plugs.
The other issue with junk rig battens is where they come in contact with the mast. This is a potential source of both chafe and noise. People do different things about this, and taking from various peoples’ strategies, we now have both vinyl tubing around a portion of each batten, and seatbelt webbing stitched to the part of the pocket that will rub against the mast. The vinyl tubing, where it was cut, felt like a potential source of chafe. It is surprisingly hard, and a little bit sharp. Carving down all those edges seemed like a potentially difficult and ridiculously time-consuming task, so instead we now have rubber o-rings pushed against the tubing ends, providing a bit of a cushion. These o-rings are from McMaster Carr (nope, not receiving anything) whose website provides detailed descriptions of which materials are suitable for which uses. The orange silicone rubber is good for saltwater – we’ll be finding out how it does with UV, which wasn’t mentioned for any of the choices.
Today we got to start tying the mizzen battens into place, which was enormously satisfying. Small stainless rings are lashed to the forward ends for attachment of batten parrels, which are lines that hold the battens near the mast; the rings will also serve for attaching various bits and pieces to do with other lines that help keep the sail where it belongs front-to-back. The goal is to make rigging on the water, after launch, as simple as possible. Instead of lots of knots that require detailed description for helpers, lines will have quicklink attachments to rings, or other easy connections. The knots that put all this together can be tied here at home, in a more leisurely way, all ready to go when they are needed.
That’s about it for the battens. For those who are looking for scantlings, this aluminum tubing is 1 1/4 inch outside diameter, and 1/16 inch wall thickness. This is roughly correct for the 175 square foot mainsail (following examples found at the Junk Rig Association website), and seriously overbuilt for the mizzen. Going smaller for the mizzen would have only reduced the weight by about four pounds total, and would have been incredibly inconvenient, and expensive, as far as ordering tubing. Going this way, we got one main batten and one mizzen batten out of each 24 foot length. If the mainsail had 12 foot battens this would not have been such an issue, but with 13 foot battens we had to go to the longer length pieces, etc., etc…
Some folks have built a junk rig start to finish in a week – it’s a temptation! But the process we’re in is enjoyable too, and I keep holding the image in my mind of going back out around the outside of Cape Cod – with the whales – and straight across to the central coast of Maine. If this rig works out, it should be a good match for that kind of undertaking. Battens are a substantial piece of the overall project, and it’s wonderful to have them coming together.
Do you worry at all about the effect such large diameter battens will have on airflow over the sail? It probably won’t matter in the lower panels, but i think it would be pretty significant in the upper panels where the battens aren’t parallel to the flow.
Hi Jeff,
Yes, the airflow issue is something I think about, particularly with the mizzen sail, because the battens and pockets are so large in proportion to the sail. It’ll be interesting to see, though – some folks talk about that standard Western sail theory, to do with “laminar flow,” is not the only way to drive the boat forward. There is discussion, particularly related to crab claw rigs, about “vortices” actually being a positive part of what makes the sail work. So we’ll see, on that. Perhaps kind of like the Western engineering take on bumblebees, that according to engineering science must be unable to fly…
It’s going to be so incredibly interesting, to try this rig out!
Shemaya
My experience is that the battens can be either very stiff in which case having a sail with some camber helps, or having bendy battens and a flat sail. I sail a micro with bendy battens. They are pairs of wooden strips that are ‘tied’ through the sail (no pockets) with cable ties and I reinforce the upper ones with garden canes in different amounts so the upper battens are stiffer. In a strong breeze the battens can bend in a S shape if they are not strong enough at the top.
One advantage and disadvantage of large stiff battens is that they reef well, but are heavier to raise.
I would be interested to see how you are rigging the top of the mast. This is one area that using off-the-peg hardware has led me to a sub-optimal set up.
Thanks
Hi Martin,
Great to get your thoughts on this. Some folks I’ve read talk about that seeing an S curve is indeed how you know that your battens need to be stiffer. Adding garden canes to the upper ones seems like a nice way to manage that. Some folks with aluminum battens have used thinner ones down lower, to come out about the same. The argument for using the same stiff thickness all the way up is for cruising, so if a batten gets bent or broken, it can be swapped out with any of the others. But with wood, like you’re describing, it would also be easy enough to swap materials around to come out the same.
I do have some concern about the weight of all this. The Paradox rig had a single block at the top of the mast for the halyard, and the winch on the cabin top, but after a while I was doing everything except the final tightening by hand, without the winch. The first setup we’ll try for the junk main is with a two-part halyard, to see how that goes. Same on the mizzen, just to make it extra-easy. But I think the winch for the main is going to be important – that and maybe a three-part purchase.(Keeping in mind that the goal is easier-than-average lifting.)
Masthead fittings have been a puzzle for me too. The first attempt is going to involve a mast band with four eyes, for everything except the halyard. This comes from the Davey catalog – available in the US through RW Rope http://rwrope.com/davey/rigging-sail-handling/mast-and-boom-fittings/davey-company-mast-bands.html (same old story, not receiving anything for mentioning these business names). The block for the halyard will be lashed above that band, using two shackles, as they talk about in Practical Junk Rig – one shackle securely tied to the mast, with a small eye strap on the opposite side to prevent the lashings from slipping down. Then another shackle through the first, that is then connected to the block. This allows the block to lay flat, with its side against the mast. I’d like to put a hefty eyebolt through the mast for the halyard block, but I’m afraid of putting those big holes in the aluminum. Mast work is next, so there will be a decision soon.
Have you noticed the photos on the blog titled Speedwelladventures.com (listed under “blogs I like”)? Her halyard block appears to be lashed to the mast…
Sounds like you’re on the water with your junk rig, again this season? I hope so!
Shemaya