Graeme wrote:

I have thought quite a lot about this, and in relation to my own project had been wondering about increasing the sail area by adding a lower panel, rather than simply scaling up the standard Amiina Mk2. (Amiina’s sail with an extra panel looks a lot better to my eye than the sail on that catamaran, I have to say - but there you go, beauty is in the eye of the beholder, I guess. And also, more by good luck than good managment, I stumbled onto 2-part sheeting on my little Amiina sail, and I'm delighted with that. Control of twist is near perfect and I can't see how that catamaran sail, with its multitude of panels, can be any better than mine in that respect.) Anyway, high aspect ratio is not aways suitable and it won’t suit my current project boat, though it may very well suit others. Marcus too is limited by the height of the mast he wants.

While always bearing in mind that experts often disagree with each other, I (not being one) continue to appreciate the discussion points you raise, and respect the breadth and depth of your experience. I also think you are being a “devil’s advocate” again David – though that is generally a not at all a bad thing. 

In line with your “smallish steps” advice, I am very keen to try a Amiina Mk2 sail of about 40 sq m on my current project (which is coming along, by the way) but my work rate is slowing due to age and it will be another year to two before I will be able to hoist a sail (if I don’t reach the finish line before the project does).

Graeme, I have to agree. Add another panel to the bottom, and everything will look better and work better, in my humble opinion as an observer of SJR, not an active participant. But to the bottom of what? To my eye, there are differences in proportion between the sails on BooToo, Amiina and Serendipity, and the top panel is split on Amiina but not on the others, so the "Amiina mk II sail" is something of a concept rather than being something set in concrete, isn't it?

No, I wasn't playing devil's advocate; I was asking questions and hoping to learn (but whenever I do that, Slieve sees it as hostile criticism, and I will never understand why). Though I have no skin in the game myself, you might have seen that I was advocating the SJR as being a good choice of rig for the proposed SibLim 10m a while ago, and I was trying to get clear in my mind the exact form of SJR that should take. To my eye and to my mind, Slieve got it pretty much right the first time with Poppy, and I'm having difficulty seeing the further developments of the rig as progress. But that's just me.

David, I’m not sure what hunch of yours it is that I have confirmed. Conjecture was all I had, as I had already said, I don’t have experience of a single sail of that size. “I would have thought…” was not intended to be an answer, it was intended to express doubt about what I had been thinking, and wondering if I had missed something.

Anyway, you answered my question, and thank you. From your earlier remark I had wrongly inferred that you were suggesting there might have been a potential problem with the sheeting system of a 5-panel sail when the sail becomes large, and this was a puzzle to me because, as you know, the sheeting forces on a high balanced sail are actually quite low. Regarding the coarse steps available for reefing, you are, of course, quite right about that. There is a small conundrum (weak point, if you like) in the split rig concept – if you divide the sail up into more panels to get finer reefing steps, you reduce the aspect ratio of the jibs. Whether this matters or not I don’t know, but also they are small anyway, and more panels means smaller still and there may be a point reached where they are not worth having. The Amiina sail is a balanced package of many considerations, and I think Slieve got it about right.

I have thought quite a lot about this, and in relation to my own project had been wondering about increasing the sail area by adding a lower panel, rather than simply scaling up the standard Amiina Mk2. (Amiina’s sail with an extra panel looks a lot better to my eye than the sail on that catamaran, I have to say - but there you go, beauty is in the eye of the beholder, I guess. And also, more by good luck than good managment, I stumbled onto 2-part sheeting on my little Amiina sail, and I'm delighted with that. Control of twist is near perfect and I can't see how that catamaran sail, with its multitude of panels, can be any better than mine in that respect.) Anyway, high aspect ratio is not aways suitable and it won’t suit my current project boat, though it may very well suit others. Marcus too is limited by the height of the mast he wants.

I agree, it is somewhat of an annoyance (though a rather minor one for me) that the Amiina sail only has a four speed gearbox, so to speak, as opposed to the six gears on other junks – but just like the analogy family car, it still does the job pretty well, and as a practical sail it is still miles ahead of the Bermudan in terms of ease of matching sail area with wind strength. As for the slow flapping leech on a long ocean voyage, this objection is completely beyond my imagination, not having made a long ocean voyage with a junk sail, and never having noticed a slowly flapping leech on my boat – except for the jibs which simply won’t behave at all when reefed. This problem, for me, has been resolved by having a proper sail catcher and not relying on lazy jacks, which is pretty much a necessity with SJR and should really be considered as part of the Amiina rig package. But maybe full length sail catchers are unproven too? I am not sure. They sure do muzzle a sail, 99% of the time anyway and the odd occasion when a bit of sail might hang over the edge is easily fixed. 

I think your suggestion of observing the development of a rig through small steps rather than one large one is quite a good point, can’t argue with that - although I do feel very grateful to innovators like Slieve (and you too David) who have in the past been prepared to take some very large steps and then share the results, with commendable honesty, from which the rest of us can benefit.

While always bearing in mind that experts often disagree with each other, I (not being one) continue to appreciate the discussion points you raise, and respect the breadth and depth of your experience. I also think you are being a “devil’s advocate” again David – though that is generally a not at all a bad thing. 

In line with your “smallish steps” advice, I am very keen to try a Amiina Mk2 sail of about 40 sq m on my current project (which is coming along, by the way) but my work rate is slowing due to age and it will be another year to two before I will be able to hoist a sail (if I don’t reach the finish line before the project does).

Its not what you would call beautiful either, is it? It was never meant to be a yacht, just a boat. I do appreciate a beautiful boat, but in this vessel I am hoping for some other, more homely virtues.

PS Marcus: I think mostly when talking about the Amiina or Amiina Mk 2 sail, we mean a scaled copy or somthing very very close. Variations such as that catamaran sail, and Fly's split foresail, for examples, have superficial similarity but personally I would regard them as different. The Amiina sail is not a protocol, but it is package of carefully harmonised parts, any of which I would not change too much without first discussing with Slieve.  Also, until proven otherwise (where have I heard that before?) I would be inclined to regard any SJR as being best utilised as a single sail (ie a sloop) or possibly the main sail only in a ketch or yawl rig (eg Dave Zieger's Wayward). The only schooner with a split sail that I am aware of is Fly and only the fore sail is split on Fly. Personally, if I were rigging a schooner, I think I would rather have contiguous sails for both, but the owner of Fly, who designed her sail plan, is experienced and will be the person to talk to about that. He's on the membership list (and also Fly will be featured in the JRA magazine some time in the not too distant future). I would follow Arne or David if I were rigging a schooner. Or people who have done lots and lots of sailing in them, such as Annie or Allan (Zebedee).

At some point you have to make a choice. You can't listen to all the experts at the same time on every detail (and most of this discussion is mere detail). Choose the rig you like most (they all have their individual strengths), and listen mainly to whoever seems to have had the widest exprience with that type of rig, in the type of sailing you want to do. 

PS Marcus, I made an arithmetic mistake with batten length in that earlier sketch, you were closer to correct with your 6m. Slieve has picked it up anyway. I've gone back and corrected that post.

How come every time I write something on the website it is immediately criticized? I wouldn't mind if it was constructive criticism, but criticism based on personal opinions amounts to what?

I don't want to get into an argument, but yet again apparently authoritative statements do not hold water.

"The first requirement of a yacht is that she should be beautiful" I would have thought that the first requirement of a yacht is that it does the job it is designed to do well and safely. A similar sized yacht that overtakes your boat when you are sailing well and leaves you behind will look beautiful regardless how angular the rig is. The second SJR I drew up, based on my Poppy experience was already well on the way towards the 'angular' Amiina style, and still sailed rings round similar boats, and with a total area of some 50 sq.m it happily spent 48 hours in the North Sea riding out a nasty NW gale with no problems. So yes, there is hard evidence that it can be scaled up, or to be more precise, the Amiina rig actually is a scaled down rig.

The practical point that “Amiina's five sheeted battens are not really enough on a large offshore cruiser” is only one person's opinion. Has anyone sat down and tried to calculate what is really required, and tried to reduce it to a 'KISS' minimum as I have? Each to their own opinion. My experience of the SJR suggests that its flexibility will allow a rig with 'only' 5 panels to be used, and so far it seems to work. Regarding sheeting, how come Bermudan rigged boats get away with only one 'batten' sheeted and still sail offshore? (Yes, that is a facetious comment).

With a full sail catcher/cover long lengths of leech do not hang down and self destruct.

Please, David, hang up your boxing gloves. Please let members ask question and we might all learn something new.

Regards, Slieve.

Anonymous wrote:

Emmm! I didn't see the inner staysail stay. The question is, what is the rig you would normally use in 5 to 10 kts of true wind. In other words, a light wind, but not drifting conditions? I ask because that is the rig area you will probably want as the basis for you future rig.

The Genoa will probably have greater area than the high-cut and staysail together, so forgetting the difficulty in setting the Genoa, which is the best sail combination for light-moderate wind sailing? Do you know the area of each sail? If not, do you know the length of luff, leech and foot of each sail, as if you do a few seconds will give us the area of each using Heron's formulae. From this information it should be possible to confirm the desired sail area.

As you have sailed the Bermudan rig, how did it balance? When sailing at best speed on a close reach, how close to the centreline was the tiller and how heavy was load to hold it there? As there is no hydrodynamic balance with the rudder the tiller loads could be a little heavy, so the angle of the tiller to the centreline may be the best guide to balance.

Yes, lots of questions, but it all helps to build up the picture.

Cheers, Slieve.

Update on sail area 

Main 22sqm

Genoa 32sqm

Staysail 13sqm

High cut foresail 20sqm

In light wind conditions I would prefer to use a full main, staysail and foresail. I feel that the power and balance with the cutter combination is preferable to using the Genoa. When the wind picks up I put a reef in the main, and as long as I’m not to much heeled over there is no problem with helm balance. 
/Marcus

Few yacht people see anything beautiful in any junk rig – until they sail with one. I’m not taking that bait. I'll just say you are right, David, about Poppy's rig - that iconic photo which Slieve still uses as his avatar really is quite beautiful.

Most of the various types of junk rig seem to scale between 15 and 50 sq m with no problems at all. I can only think of a couple of exceptions and in both cases there was nothing wrong with the concept of the larger size, the problems revolved around special componentry required. The Amiina sail requires nothing more than the sticks and string of a normal junk rig.

I would have thought that sail, with its simple componentry would scale happily within the range 15-50,  like just about any other sail. I am currently considering making a 40 sq m version. I hadn’t thought about 5-batten sheeting and admit I still have a lot to learn – could you please expand a little on that perceived problem David?

Here is the largest sail I have seen which could (at a stretch) be regarded as something like a Amiina sail. I believe it is in Australia and has a new owner who did not make the rig. I have not been able to find out any more about it, and don’t know how it performs. It does seem to have enough battens for sheeting! Its not really to my taste though. Maybe someone knows about it and can comment?

On the subject of "simple" here's a couple recorded by Worcester

Amiina is looking better already!

And then of course there's  this one

which, by the way, cruised extensively including across the Pacific.  Pretty big sails and not too many battens for sheeting...