Scampi
That is one beautiful Proa and one beautiful Lug sail!!!
I believe the lug could be as good or probably even better than the best fat-head bermudan rig. A high aspect, high peaked premium Dyneema sandwich construction with carbon spars and the works, should beat a modern bermudan any day of the week.
I love where you are going with this proa!
Cheers
Johannes
I’m ssorry if i spam your thread, but you really got me started with this split lug thing.
I made a very bad sketch of my idea. I hope it is clear enough to understand what i mean.
Cheers
Johannes
I made a very bad sketch of my idea. I hope it is clear enough to understand what i mean.
Quite similar to this: http://www.balancedrig.com/
They claim a US Patent, although I am sure I saw something that may count as prior art: a photo of a model boat in a book on multihulls published in Germany in the late 70s showed a split lug hung on a wire that was suspended between the deck and a gallows-type mast at the stern.
Regards
Robert Biegler
Oh yeah, I guess I have seen the balancedrig (TM). It seems crazy to leave that big thing at the top of your mast as you lower the sail, but I do get the reasons why he wants to do it.
Johannes has drawn the simplest arrangement, where the leech of the “jib” has some way to tension it. Another, more complicated idea is to have a balanced club boom for the “jib” mounted above the boom. This would also be self tacking, but might let you really open up that slot quite a bit. it would also take some length off of the boom, since it would extent forward of it.
I have been devouring Michael Storer’s website on all things lug rigged. The Goat Island Skiff and Beth both are pretty quick little boats with lug rigs. And both are shown in absolutely lovely trim.
It’s more tension than the junk rig would require, but fewer parts and strings and whatnot.
I would love to have no winches on Scampi. 3:1 would probably do for the halyard. 6:1 or 8:1 for the downhaul. My land proa, Palindrome, had two mainsheets per side. One that was 2:1 and one that was 6:1. 2:1 was a lot or string to pull and 6:1 was overkill for 5 sq meters. On Scampi, I’d love to shunt with a 1:1 sheet, but I’d like a 6:1 or better for cranking it on upwind. Maybe the thing to do is a twing?
Best,
Chris
Oh yeah, I guess I have seen the balancedrig (TM). It seems crazy to leave that big thing at the top of your mast as you lower the sail
It hadn’t even occurred to me that anyone might do that. I just assumed it would come down, like a yard.
I also noticed that the the rig on the Laser had holes in its top endplate, which rather defeats the purpose. And I do wonder how well the endplate works on a monohull when it heels. How do you prevent it from developing a lot of drag?
Johannes has drawn the simplest arrangement, where the leech of the “jib” has some way to tension it. Another, more complicated idea is to have a balanced club boom for the “jib” mounted above the boom.
I agree that Johannes’ version is better, and I would also go with the boom at the foot of the jib. Controlling the slot only by leach tension means it will be widest a little below the middle, and progressively narrower towards the head and foot of the sail. I would be surprised if that were the optimal shape.
Reefing might get interesting, though, much more so than with a split junk. I like reefing to be an unexciting event.
Regards
Robert Biegler
I would also go with the boom at the foot of the jib. Controlling the slot only by leach tension means it will be widest a little below the middle, and progressively narrower towards the head and foot of the sail. I would be surprised if that were the optimal shape.
I like the better slot-controll with a separate “jib”-boom, but i am afraid that it will complicate reefing more than add to the performance. I am really intrigued with this split-lug. I think it has some seriouse potential.
Cheers
Johannes
Why not a dipping lug like the sailaus use in PNG? It’s a crabclaw that turns into a lug sail and seems to work really well on their less that optimal hulls…
You tube vid shows them really flying! Balanced in either configuration too.
I would love to have no winches on Scampi… ...Maybe the thing to do is a twing?
Twing?
Chris Gill has a rather enticing take on this
“I only need two camcleats. The forward one grasps the tackline, the rearward one holds the mainsheet; they exchange roles after a shunt. Lack of a double-block downhaul, which would be difficult to arrange on a boat with two mainsheets, is not the problem I thought it might be; if one needs the mainsheet tighter just point a little closer to windward and the strain comes off. Pull it in and bear off again.”
A twing is a line the bowstrings another line. So a barberhauler is a twing. The idea is to have the sheet be 1:1 and another tackle would bowstring it.
Heading up to sheet is totally doable. But I feel like, with all of the simplicity of the lug (one halyard, one downhaul, no sail track) I’ve earned a little racy nonsense.
So I was messing about with Scampi and discovered that I had been drawing it 27’ long this whole time. I used the bones of Palindrox to build it, and that was how long Palindrox had gotten by the time I got everything on my list.
Scampi is about being absolutely minimal. So I had to shrink it down. It looked kind of dumpy shrunk by 3 feet, so I nipped and tucked throughout, less freeboard, less beam, I shortened the house and the pod by a foot (its now 7’ long), I lowered the house and generally squeezed it down until it looked good again.
I also simplified the bulkhead arrangement. The two full width bulkheads are pushed out to the hatches and a fore-aft bulkhead ties the mast to them. That bulkhead is pierced with holes to make some handy cubbies.
I think I’m back to the idea of hard hatches on top, fabric, zip down, hatchboards. I put a lip on the floor of the cockpit which we’ll fix with a full sized closed cell foam cushion. It is a cruising boat after all…
Sure is pretty with the inside all bright.
chris
I was thinking to myself just a few days ago: “Wouldn’t Scampi be nice with a standing lug rig?” and voila.
They say that an uncertain sense of scale is a good thing in a design, that it “looks right” whether big or small, though in this case, I doubt if 3 feet proves the point. Nonetheless, thanks for checking the scale, and the design hasn’t lost a thing, still lovely.
I’m looking at that blank wall in the cockpit between the hatches, it would make an ideal spot for navigation electronics, or a portrait of Lao Tzu or St. Christopher.
Thanks, Michael. I’m glad its still looking rightish to your eye.
That’s a good point about the “dashboard” area. Its probably a good place to put the GPS, and/or a chart holder.
I was thinking about how Scampi is sort of an alternative universe version of your Manu Kai—a little camping boat for two at most. Manu Kai is a bigger boat, and much simpler in terms of foils. But, Scampi has an even more simple rig and structure. I’d love to see Manu Kai in production—talk about a boat that looks right.
For this refinement of the design I lengthened the boom, added full battens and, since I had the battens, a bit of roach. All in all it brings the sail area up to about 235 square feet on a 27 foot mast. I love how little hardware is involved, and how it all lashes together. And I absolutely love how it looks. The battens and roach modernize the look in a cool way.
Michael Storer’s Goat Island Skiff has full length battens in its balanced lug. He said that he can take them out if he wants to power up the sail, or put them in to flatten it. I find that idea enticing. They might help the sail find its shape when the mast is on the “wrong” side as well. I’ve put the mast about 25% back from the tip of the boom. That’s more than most balanced lugs. I wonder where the practical limit is. As its drawn here, the CE of the rig is about 37 inches aft of the mast axis and 7 inches to leeward of the mid line of the vaka. That’s with the boom sheeted in 15 degrees from center line (which is what Michael Storer says is fully sheeted for a close reach on his lug rig).
But the big question is, can a lug perform efficiently enough on a multihull that is going to be (hopefully) traveling at better than 12 knots? With carbon spars, battens, low stretch sails and running rigging, can we get enough efficiency out of this simple, self vanging, balanced sail plan.
What do you all think?
I might just buy a CLC 62 sq ft. lug sail for my Wa’apa to get an idea. Its a bit spendy at $500, but the development time that I’m sure they put in to get it right seems like a good idea compared to just ordering one up locally.
Best,
Chris
Here are some more shots…
and three views…
Scampi is looking really really good. As far as your lug sail, it should work quite well, I saw Mik Storer and John Goodman fly by in the GIS in 2010 TWS and they were flying (for a monohull 😉 . One real advantage of a good lugsail is simplicity and effectiveness of reefing. 235 s.f. of sail on a less than 1000# of boat gives you a Bruce # above 1.5 hardly easy cruising territory. Would be interested in what your wetted surface turns out to be, a lot of fairly expensive boats, or their owners, might come to seriously dislike you in a lot of conditions.
Cheers,
Skip
...a lot of fairly expensive boats, or their owners, might come to seriously dislike you in a lot of conditions.
Cheers,
Skip
Sound like a good enough reason to build a boat… :o)