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Erick Singleman
08-09-2000, 09:14 PM
Can someone please explain the difference in the various lug rig designs, particularly the standing lug rig, and the balanced lug rig?
How do the differences influence performance?

ACB
08-09-2000, 10:05 PM
OK; I'll try.

Dipping lug. The most powerful, but the hardest work. No boom. Tack of sail belayed forward of the mast. Yard must be "dipped" to the other side of the mast each time you tack. This can be done either by releasing the tack, hauling smartly on a dipping line belayed to the yard at the throat, and bringing the tack across, usually with port and starboard tack lines, or by lowering the sail and hoisting it on the other side.

This is the lug rig used on the main and/or fore masts, and sometimes all masts, of Scots fifies and Zulus and on French bisquines, chasse-marees, etc.

It should be noted that the big Scots luggers used the steam capstan on the halyard!

Standing lug. Fitted with a boom. Tack of sail at gooseneck. Used on dinghies, and sometimes on the mizzen sail of larger luggers, eg Suffolk beach yawls had dipping lig mains and standing lug mizzens.

Balanced lug. Fitted with a boom, which extends past the mast, and is held to it with a parrel. Exclusively used on small craft on sheltered waters, eg sailing canoes.

TomRobb
08-10-2000, 08:31 AM
Well, yes, everyone claims they pull like a draught horse at little cost, but they sound like there's a huge hassle factor penalty and ability to tack quickly.
Just how do the differences affect performance?

Frank Wentzel
08-10-2000, 03:12 PM
IMHO the best lug rig is the chinese lug or "junk" rig. Low tech, low stress, no deck winches, no deck-work, easy reefing, low CG - what more can I say? Made of the proper materials it is not as nearly as heavy as it is reputed to be. Doesn't require halyard winches or expensive hardware. Due to the distributed stress and no flogging the sailcloth lasts almost forever. Tom Colvin's tests on identical sharpie hulls indicated it was not appreciably less close-winded than the bermuda rig. Blondie Hasler's junk-rigged "Jester" crossed the Atlantic so often it almost wore a rut.

B. Burnside
08-11-2000, 01:07 AM
In our family we have used lug rigs on several boats. One was designed as primarily a sailboat, and the lug was chosen because the owner wanted to sail single-handed frequently, and the lug was the simplest to deal with alone. The windward performance was surprisingly good, IMHO.

The other lug rigs have been on boats primarily designed for rowing. Rowing and sailing require different hull shapes, and what's good for one purpose is rarely good for the other. Rowing boats need as little wetted surface as possible, narrowness and all that, so if you tried to go to windward with a shape like that you'd get quite frustrated and quite wet, and maybe upside down. So a downwind sail is better for those guys anyway. And plenty exciting! The slippery skiffs go like smoke with a generous lug.

Another advantage of lug sails is they can have freestanding masts. Rowing boats usually aren't built for the stresses of stays and shrouds, for one thing. And when you decide after rowing for a while, that you have a favorable wind, it's really nice to have a small, light, simple rig you can put up out in the briny, without having to get all complicated ashore first. You can take it down just as easily, if the wind dies on you.

These rigs were all dipping lugs.

Scott Mason
08-11-2000, 02:45 PM
Hi Erick, in WoodenBoat #73 Iain Oughtred has an article "Variations on the Lugsail" which explains the differences and evolution of these rigs. To summarize what Iain says
"the balance lug rig is a simple and logical development of the boomed standing lug. The boom and tack are simply brought forward to overlap the mast by up to 1/7 of the length of the foot. This changes the behavior of the sail considerably when the sheet is eased, in that as the boom tries to lift it is prevented from doing so by the tension in the luff. Thus, when running in a fresh breeze the twist in the sail is very much reduced. ... Overlapping the boom and sail keeps the sail more rigid, making it more manageable as well as more effective for downwind work."

Overall, Iain describes the advantages of lug rigs as: low cost, good driving power on short spars (i.e. can store rig in the boat)and a sail plan that can be quickly reduced. From the perspective of this beginning sailor, they sound like just the thing for small open boats.
Scott

Jim M
08-11-2000, 08:50 PM
I have yet to ascertain any advantage to a standing lug over a balanced lug, except that a standing lug might is certainly easier to brail up to the mast (e.g. at lunchtime), since the boom pivots at the mast. But that is exactly why it behaves badly downwind -- the boom, held fast at the inboard end, lifts at the outboard end, the sail twists, the rig jibes, the boat capsizes, if not for the courage of the fearless crew, the Minnow would be lost.

One of the sailing canoe pages has a diagram of a balanced lug rig with a "jack stay" to hold the boom of a balanced lug rig UP when the halyard is loosed, which is convenient for reefing. To unrig sail from mast, the "jack stay" is easily cast off. This reduces the advantage of the standing lug over the balanced lug to zero.

dadadata
08-12-2000, 02:40 PM
http://www.friend.ly.net/~dadadata/

will get you links to a bunch, and I mean a bunch, of canoe sail lug rig diagrams.

I've sailed a balanced lug for years on the little Bolger "Peero", as 12-ft sailing canoe-sharpie-thing, and it works fine.

The CLC "Eastport Pram" has a standing lug and I've sailed that a lot too.

All said I prefer the balanced lug because the boom doesn't lift when running. This isn't a big deal on the Pram, because the sail is small and the pram is very stable, but I wouldn't want to cope with a lifting boom on a much larger sail or on a narrow boat. I'm lazy, and not athletic, when sailing.

The Pram's "standing lug" is very easily converted to a halanced lug simply by bringing the boom forward eight inches or a foot and tying a tackline there.

A standing lug can have a gooseneck or a "Y" shaped or half-Y shaped yoke a-la a gaff rig's gaff or even just a tie to the mast & a tack with the boom not physically attached to the mast.

I think Bolger, perhaps others, have shown a standing lug with a sprit boom, which might be a reasonable compromise, but I haven't tried this.

Standing lugs can be used without a boom, BTW, and FWIW.

I have seen diagrams of balanced lugs with tacklines which run back to the base of the mast from the fore end of the boom. Apparently used only on smaller boats? I can't recall where I saw this, I suspect in an old RUDDER.

I am completely in favor of a 3/1 purchase on any lugsail's tack downhaul. If you can get that luff tight, and the spars and mast are substantial enough not to bend, you can have a very well-setting sail indeed. The cost of a nice Harken block is maybe 6 or 7 bucks for any small lugsail and well worth it.

Mike Field
05-07-2001, 05:01 AM
Well, I'm half-a-year-plus late with this, but here goes.

Craig, the balance lug with a tackline is exactly the rig I use on my kayak. I can't imaging anyone wanting to use it on a much larger vessel, though, because it's the tackline that keeps the boom cocked up to the right angle -- the gaff is supported by the halyard about 1/4 the way from the throat, so without the tackline the whole rig would want to swing down and forward until its CG was at the mast (probably means the boom is resting on the gunwale before then, though.)

Erick, if you're still waiting to get afloat after all this time, you might consider a sprit rig as well as any sort of lug, too. But I won't enlarge on it unless you want more info.

ACB
05-07-2001, 05:27 AM
Well, now we are back to it, what rig would you advise for our launch?

She is 16' x 6'2", lapstrake, with a triangular false keel which gives 1ft 10" draft at the heel, with a Yanmar 1GM10 swinging a 12" 3 blade prop. So she has ample stability, but with the prop drag she is unlikely to be a star performer to windward.

I am tempted by the dipping lug, because the yard and sail can easily be stowed inboard when in motorboat mode, taking little room, but just about every dipping lugsail boat I have seen has a mizzen, so that complication, if necessary, would negate any benefits.

Options are a single standing lug, like the "Swallow" in Arthur Ransome, or a gunter sloop. The last has the most gear, but is easier for children to sail.

Mike Field
05-07-2001, 10:23 AM
Hell's bells, Andrew, what are you asking me for? You know just as much about it as I do.

As you say, she's unlikely to be a star performer with that drag and displacement, so for what it's worth, I guess I'd probably go for the gunter to try to make sure she'll go about all right. (It's a bit embarrassing having to poke an oar out to give a shove every time you tack. And the spars should still fit inside the boat OK.)

However, this is a bit theoretical with me, as I haven't sailed a gunter rig myself, only read of others' experiences with it.

Could you live with Frank's suggestion of the chinese lug? I understand it's a very simple one to handle -- firstly the sail's partly balanced, second it's fully battened, and third each batten is tied to the mast with a parrel, making it easy to handle and reef. (I don't know how easy it is to set or hand.) On the other hand, I for one have never liked the look of any chinese rigs, and there's so big an emotional investment in a wooden boat that I don't think you can afford to offend any of your senses with something that doesn't seem "right." (Just one person's opinion, of course.)

Hasn't helped much, has it? Sorry.

ACB
05-07-2001, 11:02 AM
Thanks, Mike, you HAVE helped. Gunter lug it will be. Your point about getting her to go about is the clincher - on our narrow twisty mooring ridden little river, with its "Troublesome Reach" and wooded banks withf luky winds, a boat like the good ship "Piglet", with her rather inadequate launch type rudder will need all the help she can get. And as you say the spars wil easily go in the boat.

Andrew

Mike Field
05-07-2001, 11:58 AM
Well, how about that! http://media5.hypernet.com/~dick/ubb/cool.gif

Bill's in the mail.