Richard,

I haven't time to look at this in detail today, but would agree with making the sail 4.5m wide, as the fabrics we prefer are generally 1.5m wide (three vertical cloths in each panel). I'll be able to lend you my industrial sewing machine, which will cope easily with Weathermax 80 or LT.

DAVID

Thanks for your input. As you can see I am still weighing up all the possibilities. The project may take me all year and I know you’re away at the end of April. On balance I would like to try and make the sail myself, I am always in need of a project to keep me busy!  Maybe it’s impossible though with my current machine.

It looks like a tossup between your Weaverbird rig and Arne’s. Do both your sails involve hinged battens? I wish I had looked more closely at your when we were there to see how they were done, but I was not really considering the rig for my own boat at that point.

Arne’s latest post seems to contradict your views on mast position, it’s rather difficult for a newcomer to weigh up these matters and I don’t want to be ruffling any feathers! What is your view on the CE and possible weather helm? I certainly don’t want to spend all this time and money and end up with problems though I appreciate there are no really definite answers in this game.

Richard

Richard

Your drawing confuses me a little. I see now that it is a twin keel version. In addition it appears to have a somewhat different superstructure than the on I found on Sailboat-data.

Another thing is that you have shifted the CE quite far aft compared to the Bermuda rig. Unless the boat carries a lee helm with the Bermuda rig, I would warn a bit against that. In addition, these boat appears to have a shallow and not very big rudder. In that case I suggest you keep the chord of the sail down on 4.5m or less, like the one David has suggested. The shorter chord reduces the increase in weather helm as you bear away onto a reach or run. I had a wide-chord sail on my Johanna, but got away with it because of the big, efficient and semi-balanced rudder.

Now I have added an alternative mast to the AR=2.10 sailplan (33.6sqm): By giving it a moderate aft rake of 1.6deg, the partners can be moved to the foredeck where it is much easier to install. As the sail itself will not be moved forward, this change will not rob any more deck space than with the plumb mast. The CG of the mast will only move a little forward. If you can get the weight of the mast down to 2.5% of the boat’s displacement, you should be all right.

Handling forces:
I would not be worried about the sheet forces, even with low-balance sails. I am far from big and strong, but sheeting my Ingeborg’s 35sqm sail is no big deal. It pays to lead the sheet forward to let a genoa winch on the cockpit coaming serve as a snubber winch. This lets you sit down and haul very effectively.

I promise you one thing: If you can hoist the sail, then you surely can reef it as well! Hoisting is like cycling uphill, while reefing is like rolling downhill  -  easy.

Sewing method:
Frankly, I think (surprise, surprise) that my Amateur Method B of assembling the batten panels is very easy. Moreover, if one needs to replace a worn batten pocket later, then all one has to do is to rip a single zigzag seam. Even better, one can easily sew on the new pocket without needing to roll up half of the sail to make it pass under the sewing machine’s arm. Check “The Cambered Panel Junk Rig”, Chapter 5.

Hope some of this makes sense...

Arne

I have been busy drafting a post and didn’t see all these replies coming in! Some of my points have now been covered. I thank David for mentioning my health issues, I guess my feeling is that I feel I’m strong enough to raise a decent size sail, the stress can come with reefing in a blow and dealing with the forces incurred.  It seems to me that a bigger sail of say 35m2 could be hoisted with one panel reefed if conditions seemed at all marginal. I would then have the extra area in light airs. I don’t want to be dead in the water!

I’ve decided that I can locate the mast in lieu of the hatch, it’s a pity to lose the light and access but in fact it would make the mast installation much easier.  I initially thought having the mast further forward would help alleviate any excessive  weather helm, which I hate in a boat. I notice that it’s recommended that the sail CE should be further back than that of the original Bermudan rig. Why is this? It would seem to be inducing more weather helm.

I have been playing with the Ingeborg 1.9 sail which looks really nice on the boat. The original listed sail area is 29.73m2. I thought that as the sail is so easily reefed I would go for about 35m2, I pretty sure these boats are a little under canvased in their original form. The original SA/D area would improve from 14.2 to 16.8. With the mast in the hatch position the CR and CE seem OK the CE seems to be about 10% of waterline length in front of the CR. Would 35m2 be OK or would I be advised to stick with 30.

Calculation of the CR seems a bit rough and ready, I did it with a bit of card cut out to the underwater profile and balanced it on a straight edge. I assume that will be near enough for practical purposes.

I like David’s idea of the Weaverbird layout, with a simpler 6 panel layout, maximum ease of use etc. The foot of the sail is further forward than the one I have drawn from Arne’s instructions.  I presume this would make the sheeting easier to operate.  I wonder if my layout is too tight here? I have to say I do like the look of the fan shape but perhaps practicality should take preference? Stress free sailing is what I’m looking for!

I’ve been thinking about Roger Taylors system of building up a sail in separate panels, more work in the loops but less for the battens. It seems to me to make the sail far easier to make on your own with a simple machine. Any views on this? 

Not sure if image below will be accessible, still trying to figure things out.

http://www.junkrigassociation.org/Sys/Profile/PhotoGallery/62669673?memberId=37771818

"More sail area, please" - I'd agree with you, Arne, if the owner were someone else. But I'm sure that Richard won't mind me telling you that he is contemplating this conversion because he has had serious health problems. Like many of us, he has had a number of boats during a long sailing career, but has now reached the point where he has to take the decision either to make sailing as easy as possible, or to give up sailing. This is what is behind my thinking on specifying a modest sail area and short yard and battens.