Jim Calver wrote:

Paul Thompson wrote:However I would not use the bolt-rope method to attach the panels to the battens again. One because of the extra weight and two because changing panels is a major exercise that requires a minimum of two people and preferably three or four. If I were to do it again given that the idea is to easily replace a panel at sea, I'd only consider laced panels as they are a viable preposition to be able to make a panel change on the water.

Cool! This is a comment I've been looking for. I was anticipating lacing the individual sail panels to the battens but a few questions;  One, what method of lacing would you use using what material for the rope? I am thinking individual lacings but a continuous run from a single cable might be advisable? Also, should there be standing bolt rope-type lashings from each batten to the upper and lower batten, independent of the actual sail material to keep the panel 'window' shape stable?  Somewhat like a topsail schooner. As to the sail edges, would a bolt-rope in the sail panel be advisable to distribute stresses along the length of the material (or layers of tape) and should ferrules (or grommets) be used for the lashing positions through the sail material?

Jim, I'd use individual lashings to attach the sail to the battens, then if one fails for any reason, the whole lot does not come down. The loadings on the head and foot lashings are not high and just about any thing will work. I've used standard sailmakers luff tape and just burnt holes (just under the rope) with a soldering iron for the lashings. I spaced the lashings about 200mm apart.

Where you do need to pay attention is the luff and leach. Here you need to transfer the load from one panel to the next. You could use an independent boltrope but I just put good patches in each corner and made a substantial luff and leach tabbings. I used webbing loops in each corner to attach the panel to the batten and to the panel above and below it. I have found that properly made webbing loops are much more durable than grommets, which always seem to start pulling out after a while.

I designed and built the sails for Carl Bostek's Aphrodite. Both sails are made up from individual panels. They have a bolt-rope on the head and on the foot, the battens have track riveted to them. The track provides considerable rigidity but they also add weight. In this case the bare batten is 8kg (this is a big boat) and the track adds 4kg.

The rig is a success in that it works as a cambered junk should. Carl is happy and Aphrodite is notably faster than she was under her former Galant rig. She is also well balanced.

However I would not use the bolt-rope method to attach the panels to the battens again. One because of the extra weight and two because changing panels is a major exercise that requires a minimum of two people and preferably three or four. If I were to do it again given that the idea is to easily replace a panel at sea, I'd only consider laced panels as they are a viable preposition to be able to make a panel change on the water.

However, I think the whole separate panel idea is irrelevant for us. The Vietnamese were dealing with poor quality materials that were weak and did not last long. In Aphrodite's case, the sails are made from Top Gun a seriously tough and strong cloth with a life expectancy of  10 years or more. The extra weight and complexity in my opinion is not justifiable.

                                                                       Stavanger, Sunday

   Using splints and wire to repair a batten inside the pocket

When using my Amateur Method B for joining panels and fitting b. pockets, the batten pockets end up sitting a bit on the "outside" of the sail. Because of that it would be possible to do a repair job to a broken batten inside the pocket just by poking a thin steel wire through the pocket but without poking through the sail itself or touching the critical panel joining seam. The Odyssey III material that I recently used certainly is tough, and the thick PVC at the mast batten pocket is even tougher, but an awl would help to get the wire through. For a long distance journey, bringin material for splints plus some thin fence wire and an awl would  be mandatory.

Arne

                                                                    Stavanger, Saturday

Jim and Brian

I have no doubt that the use of separate batten panels will work just as well as a one-piece sail when all the bits have been produced and assembled, but I bet the separate panels take just as much time to produce as my cambered one-piece sail, assembled with Amateur method B. The rigging of the separate-panel sails will take more time and the battens will take more time to produce as well.

As for need for floor space; I have just finished a 48sqm cambered panel (barrel-cut) sail. The floor space was only just sufficient for lofting each batten panel - the sewing machine table (on wheels) sometimes had to be rolled aside to allow for lofting. We (2 guys) still finished the sail in 5 ½ day. Rigging such a sail (with batten pockets) takes about 2-3 hours first time.
(PS 10.4.2022: No it takes a good deal more time. Mating the sail with the battens may take 2-3 hours, but time for adding all the extras must be added, and it depends on calm weather. The worst time thief is that of getting the sheetlets right...)

For general use I would therefore rather recommend the one-piece sail. Just look at the junk-rigged boats of today. Their (mostly flat) sails have lasted for 20+ years. As far as I know, Ron Glas still has the sails she had when I spotted her in 1989. For deep sea travellers it may make sense to have separate panels - or at least have the sail in two separate sections, laced together at batten 3. Then, carrying a spare top section on board would be useful. For the rest of us I think there is no need for separate panels, in particular today when the sail material is so tough. The (Thai?) makers of the original separate-panel sails had to do with much simpler "canvas" with a much shorter expected life.

Cheers, Arne

PS: The replacement at sea of a bent or broken batten with tracks would be (even) trickier than pulling out and reinstalling a new batten in a sail with pockets. For deep sea work I think it is better to use lacing if separate panels are being used. A broken batten can then easily be given first-aid with laced-on splints.

Hi Jim