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anneminix 12-06-2003 08:24 PM

junk rig
 
how does one tack a junk rigged sail boat. i can''t see how its done ..tks

Jeff_H 12-07-2003 06:41 AM

junk rig
 
Technically, what is often called a ''Junk rig'' is a actually fully battened standing lug rig. On a fully battened standing lug rig, the sail stays on one side of the mast and each batten is brailed to the mast. On one tack the sail and battens are pressed against the mast and the sail forms an ''S'' shaped section where the battens hit the mast, and on the other tack the sail sags away from the mast resulting in a baggy shape. Neither shape is especially good for windward performance.

In theory to tack a standing lug, you simply turn the helm and pass through the wind. But Junk Rigs are notorious for being slow in stays and historically larger junks were not tacked but wared around (jibed onto the other tack by doing a 250-260 degree turn that starts by falling off to leeward.) Smaller junks could be tacked but often depended on the crew to back the sails at a critical moment in the jibe. There was a pair of great papers presented on this at the two most recent SNAME sailing yacht symposiums.

Of course tacking is more reliable when a fully battened standing lug rig is coupled with a more easily driven western style hull. It is important to understand the different horses for different courses concept of selecting a rig. Junk rigs were developed to provide powerful reaching sails for heavily loaded, low stability, high drag boats. Beating was never a part of the plan for this rig as Oriental boats lacked any significant keels to prevent leeway. The rig and the boats were well suited to each other. Placing a Junk rig on a modern boat is something of mismatch since the hull can point much closer to windward than the rig is capable of doing.

Respectfully,
Jeff

flicker 12-07-2003 03:17 PM

junk rig
 
Please forgive my ignorance, but, if lug sails are so difficult to tack and so poor to windward, why are they being used at all in cruising boats? Is it nostalia or a love for things oriental?

Chas

Jeff_H 12-07-2003 04:25 PM

junk rig
 
I am not sure why lug sails are being used on cruising boats. The concept seem like it is being sold as a simple rig to build and fly yet it has way more components than a Bermuda rig. Getting the sail cut and flying shape correct is pretty difficult in these days where even small lofts have reasonably sophisticated cutting patterns for Bermuda sails. The design of the rig has fairly high loadings on the sail cloth and is more chafe prone.

Lug rigs do offer a lot of drive on a reach with minimal heeling but are prone to excitation rolling dead downwind just like a spinnaker. So all things considered, I am not sure why someone would go to a Junk rig.

Jeff

Billpjr 12-31-2003 01:54 PM

junk rig
 
Tom Colvin has some good writings (40-50 yrs of it)on this rig. He says it in practical terms for serious ocean cruising. He has a flotilla of cruising boats sailing with that rig and the ones I''ve met on his boats like the rig for ocean work. Also, the hard core cruisers I''ve been around don''t give high priority to the "highest" pointing ability and have NO concern for handicap ratings.

I''ve thought about trying a lug rig. Reefing is easy and the lack of a headsail eliminates that job. Tacking hasn''t been an issue with Colvin designs. Basically, the hull has to be designed to work with the rig. The downside is not being able to heave to easily (or at all). It doesn''t have foil so sail building is simple for the homebuilder. Shorter rig for shallow draft, etc...

Jeff_H 12-31-2003 02:53 PM

junk rig
 
I don''t know if you have ever actually reefed a fully battened lug rig (junk rig) but there is nothing easy about it. It is way harder than a two line slab reef to put in and can really be pretty wild during that period that the halyard is slacked and the reef has yet to be tied in as the yard is whipping wildly overhead.

I don''t know who told you that a lug rigs do not have a ''foil''. Lug rigs are broadseamed (cutting the fabric at the seams to create a wing shape) just like a modern jib or Bermuda sail. The issues with a lug rig is that there are very high loads through the middle of the sail in line with the mast and so the broadseaming needs to predict stretch across the bias of the sail in order to prevent a blown out sail shape and premature aging of the sail.

Jeff

Billpjr 01-03-2004 08:25 AM

junk rig
 
Mr. Jeff H.

Calling me to task? Ok.
Your info is flawed by lack of research, understanding and experience with the rig on cruising yachts. Whatever, it sounds like you are comparing modern full batten sails/rigs with lugs. Your avg modern day sailmaker doesn''t have a clue about lug sails. Apples and oranges guy. Your previous statement about coming about is also an exception, not the rule.

About lug foil...it is not as critical for the homebuilder to cut and sew successfully. Sail shape is adjustable with a lug. There is complete adjustability of the leech and total adjustability of the sail. The lug sail can be adjusted to spill the upper portion of the sail yet have the lower section drive. Reefing under moderate conditions requires only dropping to the next batten and no tieing ends...etc, etc, etc..

So where did I get my info from?
I won''t go into detail on 45+ yrs of owning (marconi, gaff, fractional, sloops, ketches, schooners, full keel, fin, centerboard, monos, cats, tris) and sailing up to 90'' but that is part of the source. Included in that was about 3 months anchored a stone''s throw from Tom Colvin and his 48''lug rigged vessel K''UNG FU-TSE down in the islands. Many times observed him sail in and out of harbor...on or off the hooks and no motor running. That included reefing and other tasks with the rig. I also spent those months sitting on the fantail of his boat, breaking bread, chatting about boats and rigs with him. You could say it was an education from one of the few experts on southern lugs rigs for cruising boats. I doubt there is another person alive who has designed, built and cruised and experimented with more lug rigs. Unlike most, he also has extensive experience on all other rigs.

I''ve already mentioned that Colvin boat owners who sail lugs like them. These are the people who cross oceans and stay out for years. Most had plenty of experience before selecting the lug.

There''s nothing to debate.

Bill

Jeff_H 01-03-2004 02:10 PM

junk rig
 
Fair deal, if you won''t bore me by going into your experience than I won''t go into my 42 years of experience which also includes actually owning, designing, building, restoring and sailing marconi, gaff, fractional, sloops, ketches, schooners, full keel, fin, centerboard, monos, and tris.

And I won''t get into my years of actually designing, sailing, reefing and racing junk rigged boats rather being anchored a stones throw away from one for three months and having chats on the fan tail.

When you have actually reefed one of these puppies in a blow get back to me and tell me how easy it is to get the brails in. You are right there is nothing to debate, even in China, sail powered working craft have been going over to western rigs. Yup- You are right there is nothing to debate.

Jeff

Billpjr 01-05-2004 04:52 PM

junk rig
 
You missed the point and have no idea who Colvin is do you? Here''s info: He probably has 75,000+ miles sailing lug rigs and double that in traditional rigs (approx 75 yrs actual sailing, designing and building). Dozens of his lug rigged designs have done circumnavs and likely add 10x to his miles. There isn''t another architect or sailor around that comes close to his background with lugs on ocean going yachts. Since you are contradicting experts with extensive experience on lugs and more than you ever dreamed of. What makes you right and them wrong?





Jeff_H 01-05-2004 06:18 PM

junk rig
 
I know precisely who Colvin is. I have read hic books, sailed his boats, and designed a correction to successfully improve the balance and handling of one his designs.

Given that Colvin and the other lug designers are a very small minority in the bigger world of more conventional designers, and given that Colvin himself has vascilated on using lug rigs on his boats, using a wide variety of rigs within the succession of designs that he has drafted, and given that the attributes of lug rigs are well understood by those of us who have bothered to look into them, and given that the millions of miles sailed by people who chose not have lug rigs far out number the comparatively few choosing lugs, and given that even Anne Hill chose to eschew the lug rig for her present boat after experiencing what I consider a far more successful lug rig than anything that Colvin has ever designed, and given that I have sailed some Colvins that were miserable sailing boats, which you would think if Colvin was so perfect in his experience driven infallibility such a poor sailing boat would not occur, given my own experience in redesigning the rudder to improve the handling of a Colvin design, why shouldn''t I question the lug rig even if Colving happens to like the rig and what makes you (or he) think that you are right and the rest of the bulk of the known sailing world is wrong?

Look if you love the Lug rig so much build one for yourself and enjoy it. I never fault a person for living by and testing out their beliefs. In certain kinds of vessels and in certain sailing venues fully battened standing lug rigs (otherwise known as ''junk rigs'') actually do make sense. Once you have actually sailed one for a while in a range of windspeeds and compare your experience with some of the other rigs you claim to have experienced, and if you can be intellectually honest, you will probably find lug rig''s advantages pretty small and their disadvantages pretty large.

Look there are all kinds of proponents of all kinds of craft out there. Many have tremendous experience with the type form that they advocate. At times these folks adopt a belief with the intensity of a new found religion. People with that kind of fanatical faith I can only wish well. I do listen to what they have to say and try to distill what I can from them about why they think that a particular idea makes sense. In some cases I will make an effort to experience and understand their case for myself. I also try to read conterpoint and see what else is known about the topic. And only then do I arrive at a position.

Perhaps our difference between us is in our approach to understanding the lug rig. Our approaches represent the difference between a belief in science vs the belief in an individual. I believe in the science and the testimony of the experiences of many who have studied this rig in depth and you are asking me to believe in your version of one dissenting man''s opinion. Again I ask you your own question, "What makes you right and all of the vast majority of rest of the sailing world wrong?"

Jeff


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