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Thread: Ilur Balanced Rig sail shape/geometry

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    Default Ilur Balanced Rig sail shape/geometry

    I am building an Ilur based on the design from Francois Vivier. One of the winter activities will be making or purchasing the sail. I have the overall size from the plans, but in terms of sail shape it only states 'generous belly'. When I asked Francois for some advise, he told me that he is more of a naval architect than a sailmaker. Therefore, he unfortunately could not give me tips on the shape.

    In SailCut, I designed the sail based on the dimensions from the plans, but the shape/belly to me is still guesswork. Does anyone have tips regarding the shape/profile of this sail? Right now, I'm just choosing the parameters based on what feels right on the particular moment.
    Sailcut.jpg

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Get a copy of David Nichols excellent book on traditional sails. He provides formulas for varying the draft using luff rounding and broadseaming.

    https://www.amazon.com/Working-Guide.../dp/1891369679

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    Default Re: Ilur Balanced Rig sail shape/geometry

    I suggest hiring a sailmaker to figure it out. I don’t know how easy it is for you to find one in your area experienced in lug sails. There are ones in the US and probably the UK. I have Nichol’s book it is fun, but I don’t think it tells you enough to build a sail from scratch and get it right.
    Last edited by Matt young; 05-18-2019 at 06:29 AM.
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    Default Re: Ilur Balanced Rig sail shape/geometry

    Todd Bradshaw literally wrote the book on sails like these, which is available from our kind hosts here at WB Magazine - https://www.woodenboatstore.com/coll...ucts/canoe-rig

    He may also chime in on this thread.
    "The enemies of reason have a certain blind look."
    Doctor Jacquin to Lieutenant D'Hubert, in Ridley Scott's first major film _The Duellists_.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Yeah, but I purposely didn't get very far into the nuts and bolts part of sail design in Canoe Rig. It's too complex of a subject and would have added about 300 pages of really tedious stuff which I probably don't have the patience to explain well.

    I don't do Sailcut, and they don't use the same methods that traditional sailmakers use so their figures are meaningless to me, but looking at your cross sections, you have designed a fine sail.......for a very light, fast, easily accelerated and skinny multihull that won't carry much weight and which is piloted by a really good skipper who pays very close attention to his sailing angles and seldom screws up. The colors are nice though.

    Who was it that said "You can't design a good sail if you don't know how?" Oh, that's right, it was me. The Ilur is a chubby little bugger, and in order to generate enough power to push it through a chop, you are going to need some draft to create that power. You're looking for at least the "typical" 2.7% draft (2.7% of chord added as luff round to generate 1' of draft per 10' of chord) or even more. Those sail cross sections look awfully shallow for such a beamy boat. Your luff entry angle is also very flat (shallow). While this can be good for generating speed on fast hulls, it comes at a price. A flatter entry tends to be more demanding of the sailor's ability to keep it trimmed properly when going through changes in boat speed, wind speed and wind angles. If he isn't paying close attention, the sail is more likely to be stalling out frequently, or just not performing well. Even quick boats like beach cats will often have rather rounded luff entry curves to help even out the performance as they transition quickly through changes in the wind pressure and direction. Entry angle is generated either by the amount of luff broadseaming on traditional sails, or the amount of panel shaping (curved panel edges) on computer designed sails. I have no idea which Sailcut uses, but you need more of it.

    By far, your best bet if you want to make the sail yourself would be to have Sailrite plot you a kit for it. If you accurately answer their questions about your intended use and your probable typical boating conditions they can design one to suit your needs and your hull. You will still have plenty of work to do, and neatness counts, but the design work will be done properly from the start.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    If you are looking for pros with experience with traditional sails, I can say that Stuart Hopkins of Dabbler Sails does great work with traditional sails. When Todd Bradshaw didn't have room to take on making my standing lug mainsail, I went to Stuart and was very happy with the results. Way happy.

    His website might be worth a look even if you want to make your own sails. Lots of info on calculating spar bend, sail details, etc. Check the "Appendices/Useful Info" button at the top of his site:

    http://www.dabblersails.com/

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by Dusty Yevsky View Post
    Get a copy of David Nichols excellent book on traditional sails. He provides formulas for varying the draft using luff rounding and broadseaming.

    https://www.amazon.com/Working-Guide.../dp/1891369679
    Not sure that is true. I found it kind of worthless, or a book to make simple things complicated in an easy kind of way...

    /Mats

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by Dusty Yevsky View Post
    Get a copy of David Nichols excellent book on traditional sails. He provides formulas for varying the draft using luff rounding and broadseaming.

    https://www.amazon.com/Working-Guide.../dp/1891369679
    Dont, its not worth the paper its printed on.
    While some of the information he's cribbed from other publications is ok, there is much in there that I dont agree with.

    John Welsford
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    Default Re: Ilur Balanced Rig sail shape/geometry

    A while ago Todd Bradshaw posted a very good description of how to build the shape into a balanced lugsail, thats a good guide.

    John Welsford
    An expert is but a beginner with experience.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    I used Sailcut 4 20 years ago when I had to make a balanced lugsail for a Bevins Skiff. It worked fine and it was easy to make templates for a whole bunch of sails for a Family Boatbuilding program during the Hiswa in Amsterdam. If you go that way you might increase the depth to 10 or 11 % in the middle.
    I often make lugsails, check out 'Two luggers at play' on Youtube: I am the guy in 'Lucia'.
    If you want my opinion /advice/sailquote, just pm me.
    Frank
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    Default Re: Ilur Balanced Rig sail shape/geometry

    Thanks for all of the feedback. I’ll contact Frank and take it from there.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    I'm about to get a new main for my 18 ft traditional gaff sloop, she's heavy and stable, so has a lot of rag up there. But finding a sailmaker today who really knows his stuff about gaff rigs is problematic. So I'll be sitting down with the sail designer, he runs the sail design and cutting service and the "sailmaker" just stitches it all together these days. I'll be working on panel shape, round in the head, luff and foot, batten position, draft and draft position and so on with the designer using his computer program. I'm looking forward to that, and expect to be doing the same with him when I need a big balanced lug for the boat that I have in build.

    John Welsford
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    Default Re: Ilur Balanced Rig sail shape/geometry

    What are everyone's thoughts on loose footed vs laced foot on the balanced lug?
    There's the plan, then there's what actually happens.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by BBSebens View Post
    What are everyone's thoughts on loose footed vs laced foot on the balanced lug?
    loose footed is faster.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    I have spoken to Frank and based on our conversation updated some of the geometry. Would this suit my chubby little Ilut bettter?
    Sailcut_R3.jpg
    Ps. This is a small image of the current status of the Ilur. I hope to flip it soon.
    Ilur.jpg

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Not much better. The cross sections shown are like taking chunks from three different sails with three different purposes in mind and trying to combine them into one sail. Think of it this way - when you look at the plan or sight upward from the cockpit while sailing, the cross sections of the sail will change somewhat at various altitudes above the deck, but there should be some sort of fairly obvious "echo" from one to the next as you look up and down the sail. This is easily visible on a well cut sail when it has been fitted with draft stripes.

    Depending on just how far down the lower cross section is supposed to be, the bottom here looks too flat, its entry angle is still too shallow, and the point of maximum draft is way too far forward. Look at how much of your total sail area is located in that lower third or so of the sail. It would be a shame to not get much use or power out of all that area.The middle has better draft, but the point of maximum draft is still most likely farther forward than it ideally should be and its cross section doesn't seem to go well with the upper and lower ones. The top could probably use a bit more draft. I don't know whether the program figures in upper sail twist or not, but there probably should be at least 7-8 degrees or so of twist figured in.

    I would be surprised if the leech, even with a couple of leech broadseams can work without flapping. They are generally hollowed a bit to keep them firm and flap-free, especially as the sail ages. No indication yet on what the program plans to do with the leech or foot roach in terms of shaping to keep them from flapping.

    BB, probably at least half of the sails I built over the last 20 years or so before retiring were lugsails, and nearly all were vertically-cut and loose-footed. It yields a bit more shape adjustability for the lower third of the sail, and mainsheet tension with fairly light, bendy booms is less likely to pull all the draft out of the lower part of the sail.

    You can see the twist, the draft, a rounded entry angle, the slight leech hollow and the smooth transitions of related cross sections as you look up and down the sail here. This is what you are shooting for when designing a lugsail. Sailmaking isn't terribly difficult, but there are a lot of little factors which you have to account for and juggle in order to get a good result. Many of them may be tiny little adjustments, but they all add up in the end. From what I've seen so far, the home study (or perhaps more like "no study") sailmaking computer programs are awfully weak at best, and too often a great way to waste a couple hundred bucks worth of expensive Dacron.
    Attached Images Attached Images

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Thank you for the feedback. I’ll try to implement the comments you provided and see if we can come up with something proper in one of the next iterations. I’ll attach the sailcut cad file too so that you can play along at home. Maybe it is easier for you to explain shapes via figures/examples than via text.
    Last edited by SuperR; 05-21-2019 at 12:18 PM.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by SuperR View Post
    I have spoken to Frank and based on our conversation updated some of the geometry. Would this suit my chubby little Ilut bettter?
    Sailcut_R3.jpg
    How do the curves on the right translate to the curves of the head and foot, and broadseams?
    Are "top", "middle" and "bottom" alternative terms for "chords"?

    Don't trust me on this, but my gut says that the leech should be hollowed with a max of 1" or so in the middle (unless battens are to be used); the foot have a convex curve with max about 2" 45% of foot length from the tack; and the head a convex curve with max about 1" 45% of the head length from the throat.
    NB I have little experience with lug sails and I don't know the size of your sail.

    /Mats

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    Default Re: Ilur Balanced Rig sail shape/geometry

    This one has an even more 'generous belly' as Vivier would describe it.
    R4_1.PNG
    R4_2.PNG

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    Default Re: Ilur Balanced Rig sail shape/geometry

    SuperR, in this crosscut sail I would use 3 short leech battens and have a slight roach of about 10 cm. The idea is that the sail twist better, but it will do this anyway better when the sail in on the wrong side of the mast. I think Michael Storer will confirm this. With vertical cut I would make the leach hollow, no battens here, and the hollowness would be 1 % of the leach lenght, say 6 cm. I would have a foot roach of about 8 cm, 2 % of the foot lenght.
    The sail looks here to powerful and I hope I did not get numbers mixed up.
    I am afraid that you are making the twist to big, but have not yet the program so cannot see it in a wire frame.
    It is hard to guess the extra round in the gaff, I would guess 3 cm, 1 % would be good. In light winds the sail will show to much cloth and with stronger winds this extra wil be pulled out.
    Can you show the sail now in a wire window? Good luck with the Ilur. Frank

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Mats, I'd probably hollow the leech more like 1" for every 8-10' of leech length, and if the sail is cross-cut, add a couple of tiny and straight leech broadseams (1/8" deep, maybe 20" or so long with no flair). They will help later on as the sail ages. I suspect that the program generates shaped panels with consistent seam widths (computer plotter-style) rather than straight panels with variable seam widths (traditional broadseamed sailmaking) so the leech broadseams would be built into the panel shaping if the program is aware of the need and reasons to have them (which it very well may not be).

    Since the luff on this sail is slightly over 8' long, it would also benefit from about an inch of luff hollowing. It would help keep the luff tight and allow for a bit of a reduction in luff downhaul tension without creating a wandering or flapping luff. Downhaul tension on lugsails is often being taken to extremes these days, and frequently not for very good reasons. A well reinforced luff and a bit of hollow can help yield good, firm luff shape on longish lugsail luffs without needing tow-truck-like tension on the downhaul.

    Yes, there is about twice as much twist in the figures as there should be. Especially on a sail like this where the weight of the yard falling off to leeward is at play, that much twist built in would render the top half of the sail worthless most of the time. My feeling on battens and leech roach on four-sided sails is to avoid them unless you are building a sail for a boat which will be a really great reacher, benefitting from that extra sail area out there, which is pretty much not doing anything the rest of the time. Leech battens are one of the biggest sources for tedious, expensive little sail repairs. To add them just to theoretically increase twist is first of all, not needed, and secondly adding to the fragility of the sail. For a tiny roach, they just aren't worth the extra liability and the pain in the ass factor of having to deal with them.

    Unless I missed it, I'm not seeing any allowance on their data sheet for yard bend. That is just nuts, and any bend that happens (and it will happen) is going to suck the draft right out of the top half of the sail. Generally, the head round on a lugsail is a mixture of round to make upper sail draft and round to compensate for yard bend, and it isn't all that unusual to have (and need) more allowance added in for bend than for draft. They have none of either. The program knows how to make a shape, at least on paper, but considering how it always seems to be unaware of some pretty serious real world factors, I'm not so sure that it really knows how to make a great sail for the real world without some skilled guidance.

    I'll bug out, but I revert to my previous statement. Have Sailrite plot you a kit. It will also be computer designed, but by a proven program being guided by people who know sailmaking and the factors which need to be considered to do it right.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by FF View Post
    loose footed is faster.
    I dont agree, I use the ability to flex the boom to help alter sail shape, but dont at all see that it would be faster in any conditions with a loose foot.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    It's not faster and there is no reason it would be.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Again, thanks for the feedback. I have reduced the twist and hereby send you some wire frame images as per request by Frank. Maybe they'll help understanding/feeling the shape better.

    R5_1.PNG
    R5_2.PNG
    R5_3.jpg
    R5_4.jpg
    R5_5.jpg

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    Default Re: Ilur Balanced Rig sail shape/geometry

    I looks pretty good to me now, SuperR. If you want a foot with a deep roach, you might want to use a twist foot for making a dart then is easier. I think otherwise the foot will flap. What will you do with the leach, hollow or a slight roach with battens? The modern way of battenpocket making is beterr then it used to be. I have an old 'Polyvalk' gaff mainsail to repair now: It is at the end of its life but the battenpockets are still fine.

    About the loosefooted advantage: Sailtrim by releasing or tightening the outhaul works, so sailtrim is much better. On our traditional boats it is a way of life: The boom attaches 10 to 40 cm after the mast to a kind of block attached to the tabenacle. When closehauled the sail is rather flat and when running it is fuller that way.


    About ordering a Sailrite kit for a lugsail: We have plenty sailmakers in Europe who have experience with luggers, especially in France and England.
    Btw I did the Sailrite Sailmakers Course over 25 years ago. I consider myself qualified to make a lug- or spritsail. Frank
    www.oarandsail.nl

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    Default Re: Ilur Balanced Rig sail shape/geometry

    That subject can't really be debated without being more specific, especially in terms of what exactly is bending the boom and where. Even in its most simple form - with the sheet attached mid boom or a bit aft of mid boom and hanging down into the cockpit, bending the boom with sheet tension on a sail laced to the boom pulls draft (and round) out of the lower half of the sail, making the sail flatter. On the other hand, when you bend the boom the same way on a loose-footed sail, the tack and clew corners of the sail actually move slightly closer together. This increases lower sail draft, the same way easing the outhaul would.

    That makes applying more luff tension less effective in bringing the sail's draft slightly forward in stronger winds.
    In the case of lugsails (standing or balanced) you generally aren't going to be using adjustability of luff tension to move draft position in a similar fashion to the way you can using a Cunningham or downhaul on a Marconi sail. If you ease the luff tension the peak is going to droop and the luff will probably start to wobble side to side trying to find a stable position, or it will flap. For most lugs, you are far more likely to set the luff tension to be nice and firm, using pretty substantial downhaul and leave it that way.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by BBSebens View Post
    What are everyone's thoughts on loose footed vs laced foot on the balanced lug?
    My Cornish Cormorant has a losse footed balanced lug.

    If the foot is laced to the boom, you have little or no control over the depth of the camber of the sail. Also, setting up and putting away takes longer.

    On mine, I bend the tack to the boom, then use a simple clew outhaul, with an additional loop from the clew cringle around the boom to stop the boom from drooping when the outhaul is loose. It takes seconds.

    With the outhaul tight, the sail is flatter and copes better with strong winds. With the outhaul loose, the sail forms a nice belly for making the most of light winds.

    The sail is semi-permanently laced to the yard. When I come to put the boat away, I can fold it and roll it around the yard, and stow the boom separately.

    On some balanced lugs, the yard and boom are more nearly parallel, and it may be possible to roll the sail around both. (Mine has quite a high peak with the yard at a steeper angle than a typical gaff, although not quite as steep as a typical gunter.)

    I can see no advantages, and some disadvantages, to a balanced lug sail being laced to the boom.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    I"m glad you said "slightly" closer together, because, while technically correct the bend would need to be unrealistically severe for this to become significant. If a guy is going to worry about that he is also going to have an adjustable outhaul that he knows how to use.
    Most folks who aren't sailmakers would be surprised at just how little change in chord width it takes to make substantial differences in sail draft. For example, an addition of just over 1% of chord width (change from 1.6% of chord to 2.7% of chord) in round on a Bermuda sail changes the draft from 1' per 13' of chord to 1' in every 10' of chord. That is far from an insignificant difference in sail performance and the same basic thing will happen when you move the tack and clew slightly closer together on a lugsail. Whether or not "a guy worries about this" is more likely to depend on how much he actually knows about the subject.

    As for your "brutal" downhaul tension, once you have a stable luff which is not wobbling, flapping or showing signs of sagging off to leeward, there is not an awful lot to be gained by more tension. You are pretty much just prematurely destroying your sail for no good reason.

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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by Anders Bjorklund View Post
    "... bending the boom with sheet tension on a sail laced to the boom pulls draft (and round) out of the lower half of the sail, making the sail flatter."

    True, but, when flattening a sail in strong winds I usually want to retain some shape down near the foot for powering through waves. It's more important, I think, to depower aloft, where the effect on heel is so much greater.

    "On the other hand, when you bend the boom the same way on a loose-footed sail, the tack and clew corners of the sail actually move slightly closer together. This increases lower sail draft, the same way easing the outhaul would."

    I"m glad you said "slightly" closer together, because, while technically correct the bend would need to be unrealistically severe for this to become significant. If a guy is going to worry about that he is also going to have an adjustable outhaul that he knows how to use.

    "
    For most lugs, you are far more likely to set the luff tension to be nice and firm, using pretty substantial downhaul and leave it that way."

    My guru on that score is Michael Storer (paraphrasing): "Strong downhaul tension in anything above drifting conditions. Fiendishly Brutal tension in stronger winds."

    At the same time as I'm flattening the lower part of the sail by bending the boom, I'm also flattening the head by flexing the yard, the halyard position on the yard though sets what happens to the draft when I do that. I am well aware that there are different approaches to tuning a balanced lugsail, and thats one of the things that I really like about the balanced lugsail. Its a very "tunable" rig, and I've been playing with it for a very long time now, often get to race among conventional sloop rigged boats of similar potential so I have a benchmark fleet against which to measure my own boats performance. I know that Mik Storer for example has a slightly different approach, and would like the chance to try one design boats rigged as per the two different philosophies against each other.
    But for now, I'm happy with how my boats are performing with the current setup.
    I'm about to have a new main built for my little gaff sloop, improving the performance of gaff rigged boats is another research project of mine, and I'm very pleased to say that the handicapper for our local fleet views me with great concern. He's not at all familiar with traditional rigs and doesnt know what to make of a lapstrake boat with a four sided sail that cleans up.

    John Welsford
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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by Todd Bradshaw View Post
    Most folks who aren't sailmakers would be surprised at just how little change in chord width it takes to make substantial differences in sail draft. For example, an addition of just over 1% of chord width (change from 1.6% of chord to 2.7% of chord) in round on a Bermuda sail changes the draft from 1' per 13' of chord to 1' in every 10' of chord. That is far from an insignificant difference in sail performance and the same basic thing will happen when you move the tack and clew slightly closer together on a lugsail. Whether or not "a guy worries about this" is more likely to depend on how much he actually knows about the subject.

    As for your "brutal" downhaul tension, once you have a stable luff which is not wobbling, flapping or showing signs of sagging off to leeward, there is not an awful lot to be gained by more tension. You are pretty much just prematurely destroying your sail for no good reason.
    Agreed, although I do find that where the downhaul point is on the boom makes a big difference to how much tension is needed to get the luff stable. Usually though I'm pulling about 55/60 kg of tension on the downhaul of a 10 sq m balanced lug upwind, easing it a little reaching and running. I note that Mik Storer has a system of two downhauls, varying the tension on each moves the effective combined downhaul point forward and back to suit. He's one design fleet racing so has an accurate benchmark for evaluating systems. I'm mostly designing for cruisers, but like to get out racing now and again so prefer a simpler approach.

    John Welsford
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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by Anders Bjorklund View Post
    "At the same time as I'm flattening the lower part of the sail by bending the boom, I'm also flattening the head by flexing the yard"

    Agree about flattening the upper part of the sail by inducing bend in the yard. Disagree about relying on lacing the foot to a flexible boom to automatically provide the ideal amount of draft in the lower part of the sail. An adjustable outhaul, on the other hand, if unhindered by boom bend, allows the sailor to easily dial in the precise amount of draft in the lower part of the sail that he desires for each specific situation. In my much, much less prestigious opinion, of course. So I would sincerely love to be told why that's wrong.
    I have an adjustable outhaul as well. On my "performance" boat, as opposed to my cruisers ( I only have eight boats at the moment, have two more in build so will be back up to normal soon) I have an over centre lever on a five position track.
    Note that the boom and yard have both been tuned to the sail. That took a while to get right, a lot of shavings off the yard and a strip glued onto the boom.

    There does come a limit though to the number of adjustments that are advantageous, its easy for them to become a distraction when just concentrating on sailing the boat will get a better result. But its fun to play.

    John Welsford
    An expert is but a beginner with experience.

  32. #32
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    Jan 2000
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    Default Re: Ilur Balanced Rig sail shape/geometry

    One of the things we did on the techie full batten standing lug on Ran Tan was put the yard in a sleeve, with a gap for attaching the halyard. Neat and clean. It did require a recut with Stuart at Dabbler. I tested and gave him yard flexing data ( not much, its carbon) but it was baggy in the first iteration. I photographed it, and the sail went back to Stuart where it was fixed. Experimentation with lowest batten flex was also needed; needed to be stiffer than the upper battens but not too much. Sail was also designed to be somewhat self vanging with the sheet coming off the bottom batten with a triangle of sail below it to the tack. Raising the clew a little is anethema on racing boats but makes crew life much better on day boats. Lots of old time small boat rigs like that with clews substantially higher than the tack.
    Ben Fuller
    Ran Tan, Liten Kuhling, Tipsy, Tippy, Josef W., Merry Mouth, Imp, Macavity, Look Far, Flash and a quiver of other 'yaks.
    "Bound fast is boatless man."

  33. #33
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    Default Re: Ilur Balanced Rig sail shape/geometry

    I also did a full battened lugsail for a Chebacco. Looked like junk but with western shape. Boat was fast but somehow the owner found her hard to handle when lowering and he blamed the battens. After a few years I removed them and left leach battens. Bettter but not much. Then he discovered his ring with gooseneck was to small and I had to recut it to the old dimensions and it became a gaff rig as designed by Bolger. Unfortunedly I never sailed with the boat myself but I had plenty time for pictures.
    I would like to see Ran Tan with her techie rig, Ben. Was it worth it? Frank

  34. #34
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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by FF View Post
    I also did a full battened lugsail for a Chebacco. Looked like junk but with western shape. Boat was fast but somehow the owner found her hard to handle when lowering and he blamed the battens. After a few years I removed them and left leach battens. Bettter but not much. Then he discovered his ring with gooseneck was to small and I had to recut it to the old dimensions and it became a gaff rig as designed by Bolger. Unfortunedly I never sailed with the boat myself but I had plenty time for pictures.
    I would like to see Ran Tan with her techie rig, Ben. Was it worth it? Frank
    There are photos of RANTAN around on Tony Dias website https://antoniodiasdesign.wordpress....folio/harrier/

    I'm used to the full batten rig from sailing an international canoe. Rig is totally satisfactory. Not as techie as a boomed full batten rig. And we did make a mistake on the initial carbon fiber mast spec; you don't want a lug rig mast to bend unlike the rigs I'd been used to.
    Ben Fuller
    Ran Tan, Liten Kuhling, Tipsy, Tippy, Josef W., Merry Mouth, Imp, Macavity, Look Far, Flash and a quiver of other 'yaks.
    "Bound fast is boatless man."

  35. #35
    Join Date
    Oct 2005
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    Default Re: Ilur Balanced Rig sail shape/geometry

    Quote Originally Posted by Ben Fuller View Post
    There are photos of RANTAN around on Tony Dias website https://antoniodiasdesign.wordpress....folio/harrier/

    I'm used to the full batten rig from sailing an international canoe. Rig is totally satisfactory. Not as techie as a boomed full batten rig. And we did make a mistake on the initial carbon fiber mast spec; you don't want a lug rig mast to bend unlike the rigs I'd been used to.
    Thanks Ben, it confirms that full battens belong to standing lug. Frank

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