Sizing a Balanced Lugsail, Is Bigger Better?

[mikefrommontana]

Even though the boat is not "done" I still got some mileage on it last year. It is a Bolger Teal that is rigged with a 49 sq ft balanced lug. It seems to perform alright, but being a neophyte, I've no idea if it really is. It does go to windward and can ghost along down to near nothing, but I am wondering if I shouldn't have the sail somewhat larger to try to optimized results for winds between 3-7 mph, which seems to be the bulk of what we get in Western Montana.

Now the current sail is a blue polytarp (sorry folks) but it will be replaced and that is the reason I ask.

Mast is 10' 6" and is solid, if that counts. See if I can get the photo to post......

http://farm6.static.flickr.com/5212/5487071120_6841a9ceed_m.jpg

[David G]

I know a Teal that has the stock Payson/Bolger sprit-boomed leg-o-mutton. I think that one is 59 sq. ft. The other Teal I've sailed... I don't actually remember the rig. Probably the same. That would argue that your boat could take more than you currently have. OTOH, both Teals I've been in have been quite tender... and your lakes are cold, eh? I might go with a larger balanced lug and sail it reefed - as a matter of course - until I became quite familiar with the boat. Of course, it'll depend upon how good a sailor you are to start with. And how adventurous <G>

[mikefrommontana]

I've had thoughts of going up to 60-65 sq.ft. but not sure I'd gain anything in it. Worst wind (so far) has only been "maybe" 15 mph with full sail, which was interesting, but not too interesting. Of course I'm well ballasted (250 lbs) so that helps. Compared to a Harley 8 or a One Sheet Skiff, the Teal is just about palatial but pretty paltry when you get out on big water (Flathead Lake).

Honestly, while the sail rig works, it's rather hokey looking (aside from being blue tarp), and maybe that's bugging me more than actual performance issues.

[David G]

One simple way to end up with a nicely proportioned, and very functional lug rig is to copy Michael Storer's designs. His website give ample information, and you can simply scale up or scale down. Spar scantlings will necessarily be educated guesses, but you should be able to come quite close. I've got one that is 105 sq. ft. on my Goat Island Skiff. His 86 sq. ft. took me to 4th place in the World Championship PDR races (even after a bad start), the only year I entered (and believe me... it wasn't my devastating sailing skills!). It was just a very large rig for the event, and one that was quite simple to master on the fly (I'd never sailed that boat before, or any PDR. I was still bolting on parts as we carried it to the starting line).

[Thorne]

Teals are known for being quite tender, so if you get a larger one than 60sq ft. be sure to get at least one set of reefpoints added == better with two.

[MiddleAgesMan]

More sail area is probably a good idea but as the size of the sail increases so does the stress on the mast. If the mast is engineered for your current smallish sail it will be vulnerable when you hang a bigger sail on it. If you were a bantamweight it might not be anything to worry about but since you've indicated you're in the same heavy weight division as Yours Truly your mast will need to be beefed up or replaced.

[mikefrommontana]

I was certainly considering that, possibly at 45 and 30 sq. ft. Still, will more sail really make a difference in lower wind speeds?

Currently the rig is arranged following guidelines from Michalak, which are different from Storers. Rig hasn't presented any problems in handling, though changing from one to the other isn't a big dificulty. Honestly beyond 60-65 sq. on a Teal just seems to be inviting trouble. The reason I went with the balanced lug was for the ability to reef and strike sail easily--that and the stock Bolger mast will fit on the car with the boat.

[schoonerpacket]

The Teal in question is not tender that I've observed and when sailed with a good hand on the tiller and sheet. Mike is working on maximizing performance on the low wind side of things that dominate our favorite sailing pond and preparing for the midday doldrums that seem to be the norm on Flathead Lake. If we take this question beyond the Teal, does more canvas assist in light air sailing?

[mikefrommontana]

Mast is solid, being 1 x 3's laminated together before shaping. If it fails, I'll be impressed. I might try birdsmouth of another hollow mast technique on the next boat (possibly a GIS) but I want to learn as much as I can on this build first.

[David G]

The Teal in question is not tender that I've observed and when sailed with a good hand on the tiller and sheet. Mike is working on maximizing performance on the low wind side of things that dominate our favorite sailing pond and preparing for the midday doldrums that seem to be the norm on Flathead Lake. If we take this question beyond the Teal, does more canvas assist in light air sailing?

In general terms, the way I understand it is that more canvas will aid in light air performance - esp. if the rig is taller. This must be balanced with the desire to keep the lever arm of the mast shorter on such a skinny, tender boat... and the necessity to keep the scantlings down on the mast - so as not to over-burden the rest of the structure.

[Thorne]

If we take this question beyond the Teal, does more canvas assist in light air sailing?

In my experience, the more sail in light air the better. Just look out for those sneaker gusts!

My dory skiff on a windy high Sierra lake with small jib and reefed main -
http://farm5.static.flickr.com/4039/4425891502_74c3cdb0a8_z.jpg

With large jib and full main on the CA Delta in very light air -
http://www.luckhardt.com/gunkholing08/2604248905_5f99fccd09_b.jpg

[Todd Bradshaw]

A couple things.....To start with, the proportions of that particular lugsail are rather unfortunate-looking at best, both in terms of efficiency and cosmetically. It's also awfully high off of the water, probably contributing more heeling force than that much sail srea deserves. Then there is the 3-D shape. The photo is pretty small, but even zoomed-in, I'm not seeing any shaping seams. It looks like it's dead flat. If that is the case, then you can pretty well be certain that the performance will be pretty bad most of the time.

I don't know much about that hull, but in sheltered waters, with that sort of available ballast and with a reef available, I don't thing you would have a problem going up to the 60-65 sq. ft. range - but you would be wise to lower the rig a bit and go with a sail with better all-round proportions. Otherwise, you're going to be dragging the tail of the boom in the water every time you heel over much. You also might as well go with something with a higher aspect ratio (taller and a bit more skinny) because that low, horizontal shape isn't very efficient.

For example: This is a good 59 sq. ft. balanced lug, shown on a CLC Skerry. It's shown with a raked mast, but will still work well on a plumb mast.

http://webpages.charter.net/tbradshaw/!CLCSKER.PDF

Dimensions are included, including those for the spars (which I wouldn't stray far from, as spar bend is always something that has to be planned for with lugs). You do need to know how to cut a sail to build one that works properly, as they aren't flat. Another option if you want to build it, would be to have a Sailrite kit made for you, which would come with the proper shaping plotted into it.

There are a few more options here that could be scaled as needed if you wanted a little less (or a little more) sail area - but step #1 needs to be getting some decent proportions to build to.
http://webpages.charter.net/tbradshaw/!CLINTLU.PDF

[perldog007]

http://www.luckhardt.com/gunkholing08/2604248905_5f99fccd09_b.jpg

I do like that hat, boat ain't bad either. Very nice. On the little boats I've sailed with single sails and unstayed masts the procedure for dealing with a gust ( as explained to me) was more or less"let go" What does one do with sloop rig in such a case?

Does having a single sail on an unstayed rig make experimenting with a larger rig safer in general?

Mike, I'm assuming you've read Jim Michalak's essay on sail area math (http://members.fortunecity.com/duckworks/2005/0715/index.htm)

[Chip-skiff]

Here's a Todd Bradshaw sail I just got for a Bolger Gypsy, which is a 15 footer with a 4 foot beam that was drawn with a 59 sq. ft. leg-of-mutton sail.

https://lh3.googleusercontent.com/_XAqLuU8H28k/TTCi-kvYMbI/AAAAAAAABBM/S0YvG3k-8ak/s576/GypsyLug2.jpg

Didn't Bolger's design for Teal (a smaller boat) specify the 59 sq. ft. leg-of-mutton sail? In any event, I used the proportions of the Goat Island Skiff lugsail, which Todd altered slightly.

[Chip-skiff]

Poking about on the net, I found a thread on an Aussie forum concerning Teal,that included this sketch of a balance-lug rig:

http://www.woodworkforums.com/attachments/f33/70316d1206885829-paradox-micro-cruisers-bilge-runners-teal-mods-dwg-sm.jpg

Here's a link to the thread:

http://www.woodworkforums.com/f33/paradox-micro-cruisers-bilge-runners-51280/index2.html

Also found this nice photo of a Teal with the stock rig:

http://l.yimg.com/g/images/spaceball.gif
http://l.yimg.com/g/images/spaceball.gif
http://www.flickr.com/photos/jkohnen/3263930140/

The leg of mutton sail is quite good for light air, but is problematical to reef. I'd reckon that 50-60 sq. ft. would be plenty to give you a good ride without too much excitement.

http://www.flickr.com/photos/jkohnen/3263930140/

[mikefrommontana]

Todd Bradshaw wrote: A couple things.....To start with, the proportions of that particular lugsail are rather unfortunate-looking at best, both in terms of efficiency and cosmetically. It's also awfully high off of the water, probably contributing more heeling force than that much sail srea deserves.

Well, having embarked on the whole measure before really stepping foot in here.....See, you guys are great! That is of course why I asked. It's good to know that the problem is more of poor design rather than size-as I would be concerned about having to hang gobs of canvas up. Wind isn't that predictable. No there are no shaping seam inside of the sail either. Only problem is that my mast is much shorter than what Bolger intended, what would the mast on the CLC Skerry come out to (given it's a 15 foot boat vs my 12 feet)? I'd rather not have to make mast if I didn't have to--unless it's a really good idea. Anybody need a 10' 6" mast?

Thorne: Just so you know, your boat was one that kept me from wanting to reinvent my friends cantankerous/(less kindly words) Harley 8. Looks like you have a lot of fun with it.

Michael Seitz
Missoula MT

[Todd Bradshaw]

Looking through my batch of sailplans it looks like the typical sail area for nicely-shaped balanced or standing lugsails with masts in the 10'6" range is 38 sq. ft. to maybe 44 sq. ft. You have to get some luff length and more peak angle worked into the plan if you want better performance, so if you're planning to increase sail area, you will likely need a mast that's a couple feet longer. Another option would be to switch to a spritsail instead of a lug. A 10'6" mast would work fine for a sprit sail in the 60-65 sq. ft range.

[johngsandusky]

Todd's advice is golden, he's a professional.

[Todd Bradshaw]

I found a lousy, but workable, drawing of Teal and scaled it until the hull was about 12' long. Then I measured the sail area of the stock sailplan and got about 57.5 sq. ft. It is possible to put a balanced lugsail on it with the exact same sail area and the sail's Center of Effort in the exact same place (to help keep from messing up the boat's helm balance or increasing heeling, which is important). The mast would need to be 11.5' or longer in order to do this and it would need to be moved aft 6"-12" for best results, since the old rig had all the sail area aft of the mast and the new rig does not. It would look like this (the stock rig is shown in light gray in the background).

http://webpages.charter.net/tbradshaw/TEAL.jpg

So, it could be done, but it would take some work and money, plus you really do need a real sail with the proper three-dimensional shape, not a flat tarp cut to look like a sail, if you expect any sort of decent performance. The biggest question that comes to my mind is why not just use the stock sail rig? It works, and the price that Payson is carging for the sprit-boom sail made for that hull is a real bargain these days.

[schoonerpacket]

Is there a list of pro's and Con's for the Leg O' Mutton vs. the Balanced Lug? I'm thinking that perhaps some preconceived notions about either sail are not exactly true after reading and thinking on this thread.

[Todd Bradshaw]

I don't know......If done right, they're both self-vanging and for similar sail sizes, the weight aloft of the BL's yard vs. the long upper part of the LOM's mast probably aren't all that different. Draft might be easier to regulate or modify on the LOM with snotter tension and it would have more leading edge for generating theoretical lift to windward. The lug would be easier to stow, easier to add and use a reef on, and would generally raise and drop faster(drop a lot faster). The sprit-boomed LOM sails mean that the boom is less of a potential head-bonker than the BL (which has to have a boomed foot).

The sprit-boomed LOM is easier to cut and build if it matters, as long as you have a pretty good idea of how much mast bend to expect. This brings the "bow and arrow" principle into play, which can get a bit tricky to estimate. Draft in these sails is mostly formed with added luff curve. If the mast is the bow and the sprit-boom is the arrow, increased snotter tension and/or mainsheet tension tend to bend the bow (mast). As the mast bends, you start losing draft. Once it has bent enough to match the luff curve, you've lost all your draft and have a very flat sail (probably too flat for anything but an iceboat). Being able to flatten the sail to an extent is good when sailing high angles or in heavy winds when you don't need to generate a lot of power. However, one that bends too much or too early and loses its draft in situations where you still want some isn't good. So the luff curve's design and the amount of flexibility of the mast need to work together to create and maintain draft in most conditions. As far as I know, there aren't any handy-dandy formulas floating around that help to figure this out, so it's left up to the sailmaker to make his best estimate using past experience.

This, by the way, is one of the main reasons that recycled windsurfer masts very often make lousy masts for other boats. What seems like it would be a cheap, easy solution for obtaining a mast is frequently a horrible choice. On a windsurfer, the mast is pre-bent into a specific curve and pretty much locked into that shape by the boom's outhaul tackle. While sailing, it doesn't change shape much. When we try to stick that same mast on a typical dinghy and hang a different type of sail on it, the mast tends to be all over the place and changing shape with every puff or click on the mainsheet rachet. It's really hard to get consistent performance from a mast that's not under control and it's hard to cut a sail that works well on such a mast. The exception would be a boat like a Laser. It has an uncontrolled, bendy mast, but they have had decades and hundreds of sails built to tweak the luff curves of the class-legal sails to get the best all-round performance out of the package.

Compared to the LOM, the balanced lug might be a bit easier to plan for, though spar bend (the yard in particular) is still an important issue that can't be ignored. What pre-conceived notions did you wonder about?

[David G]

Todd,

I don't think I've said it before, but I really appreciate the tutorials you offer up here. I'm certainly learning a lot about an area I know all too little about.

[peterchech]

I want to second that, Todd your sailmaking experience is a real boon to this forum and to myself, thanks.

[mikefrommontana]

I certainly do appreciate your response Todd. When I first saw the Teal in the "Instant Boats" book by Payson, the Leg O' Mutton it looked interesting. As I read along (and more so after I started the build) a lot of people were complaining how tender a Teal is. Given changing weather conditions, I really wanted a rig that can be reefed or taken down if I had to and the LOM didn't really demonstrate that ability. The sail in the picture is definitely a cobble up job and I won't deny it, but it did get me out on the water and, most importantly, got me to appreciate that maybe my sail could do more.

As cheesy as it is, it has gotten me where I need to go, but it's time to look for something better built that does the job better and with greater ease. A sprit sail is an interesting option since I'm not really locked into a particular rig and have made the mast step/partner adjustable for just this reason.

[Thorne]

Just came across the pdgoose site and the overview of the balanced lug sail -

http://www.pdgoose.com/plans/welsford100/shape_head.gif
http://www.pdgoose.com/plans/welsford100/index.htm

[Todd Bradshaw]

30% is way too far forward for draft on a balanced lugsail. Even on a high-speed, high-aspect 3-sided sail like you would find on a beach cat or iceboat, the draft is seldom farther forward than 35% of chord width and most balanced lugs aren't even close to that sort of speed potential. In 32 years of making and repairing sails, I don't think I've ever seen one with the max draft at 30%. Let boat designers design boats, but let sailmakers design your sails.

[Chip-skiff]

The leg-of-mutton (which I've been sailing) is good in light air; very simple (two lines, mainsheet and snotter), and the sprit boom is fairly high so you don't get conked. Cons would be that it's not easy to reef and doing a sketchy reef with the leach of the sail rolled up moves the C of E forward and that the tall mast(16 ft. in a 15 ft. hull) tapered to 3/4" at the top makes me nervous given our local weather, which tends to deliver abrupt gusts and wild shifts in wind direction.

I'm building a new mast and spars for the balance lug sail I got from Todd, so I can test both rigs. Can't give a hands-on comparison 'til next fall, but I promise to do it.

[wizbang 13]

Yes, I have to say too, Todd know what he's talkin about.

[Todd Bradshaw]

Here is part B of the comments on the building plan above. I'm working, so this may take a couple installments.

In addition to the draft position being too far forward, the plan has another serious problem that may be even more important. In a nutshell, all that work to create draft has actually created no draft at all. If you were to lay that sail on the floor, it would still be dead flat with no 3-D shape. What has been created is round along the head and foot of the sail. This could be turned into draft, but those steps are absent from the plan and without them, you have no draft. It's like putting on the primer and then forgetting to apply the paint over it.

Let's start simple. Say we have a rectangle of cloth and we want to make it 3-D by making a hump in the middle. #1 below shows our "plan" - simple as it may be. Following the directions above, we can add some round to one edge (2). This extra cloth will be used to form the hump (draft). That's essentially as far as the instructions above will take you. If we stick some grommets into that curved edge and lash it to a straight spar, the excess from the round will form a big wrinkle, piled up near the aft side of the spar (3). Back in the days of cotton sails, this was often most of what needed to be done to sails for shaping. Through fabric stretch and instability, the excess would eventually migrate aft and form draft. Unfortunately, the high directional stability of Dacron sailcloth doesn't allow this to happen, and the big wrinkle behind the spar resists efforts to make it go away. Our excess cloth, offered up by the round isn't really giving us anything but a wrinkle, and the area aft of that is still flat with no draft being created.

http://webpages.charter.net/tbradshaw/!BS1-LAY.jpg
[side note: This is essentially how a Cunningham works on a sailboat. By pulling hard on the fabric along and right behind the mast, the draft-generating luff round is gathered into a crease just aft of the mast. As this happens, draft is reduced and the sail is flattened - desirable for for upwind sailing.]

So, our directions above only told us half of the story. They showed how extra cloth is added by using edge-round, but then the plan didn't do anything with it. What we need is a means to move that excess away from the spar and into the area where we want the draft to form, making the sail a true 3-dimensional foil. Luckily, we have such a means, and it's called "broadseaming". It's a term that most folks have heard, but not many of them really understand how it works. In concept, it's actually pretty simple and quite effective. We'll get to it in the next segment, but right now it's back to work for me. I'm working on a battened, spider-web-vertically-cut balanced lugsail for a MacGregor canoe. It's only 51 sq. ft. but contains 52 separate pieces of Dacron, so it's a rather tedious building job. When I get stressed out trying to keep track of all those panels, I come over and read the bilge for relaxation. :)

[Todd Bradshaw]

Broadseams:
If we set a baseball on a table and drape our hunk of Dacron over it, it will have a hump in the middle. However, due to the rather stiff, stable nature of the cloth, it won't be a very orderly-looking hump. What we want, is to create a similar hump (our sail draft), but one that is smooth and which gradually flows (shape-wise) from the table top, over the baseball and back down to the table. We obviously can't do this well with one piece of cloth, even after we added some extra fabric (the edge round) to cover the needed yardage for the hump. So, the way we deal with this situation is to split the hunk of cloth into multiple pieces and sew it back together with some shape built in. To do this, there are going to be some curves involved and when we're done sewing it all back together, it will no longer be a flat piece of cloth.

In traditional sailmaking, we generally leave our cloth panel edges straight-sided (rather than cut into curves) and form the needed curves by varying the panel seam overlaps. For a small-to-medium-sized sail, the typical seam overlap between panels would be in the 1/2"-5/8" range. A broadseam is simply a spot on the sail where we have gradually increased the overlap for shaping purposes, and it's usually done in spots where our seam approaches an edge of the sail. Here is an example. We have joined two pieces of blue cloth to one piece of yellow cloth. The seam overlaps are shown in green.

http://webpages.charter.net/tbradshaw/BS2.jpg

In the middle, we see our typical 1/2" wide seams, but as we near the top and bottom, the seam overlaps increase. These are broadseams and you can't see it in the drawing, but this construction now has a pretty decent hump in the middle. We normally start broadseams at, or pretty close to, the area where we want maximum sail draft to be, and they form long tapers as the seams approach the edges. The exact amount that seams get broadened depends mostly on the cloth being used. Really stiff racing Dacron gets the most (widest broadseam increases) because it is so dimensionally stable. Softer cruising fabrics which exhibit somewhat more stretch and less bias stability get smaller overlap increases because they will stretch and "self-adjust" a bit more in use. Another factor will be the number of available seams in the area to work with. Narrow-paneled constructions give the sailmaker a lot more broadseaming opportunities than sails built with 36" or even 54" wide cloth. To arrive at a similar shape, the narrow paneled sail may have a whole bunch of slight broadseams that will add up to the same total amount of "broadening" as a couple of big, wide broadseams on the wide-paneled sail.

There are some formulas in the sailmaking texts which suggest broadseam dimensions and they will be given in a format such as: "Increase the overlap 1/2" for every three feet of seam for 36" wide, firm cloth" (I just made that up without looking in a book so don't use it, it's just an example). For the most part though, broadseaming starts with a book and then takes some experience to get comfortable with. Books can't predict every situation that you may come up against and they can barely keep up with current fabric technology. Like other boatbuilding skills, getting good at it takes time, repetition and practice.

You may have noticed that when we broadseamed our drawn panels, the panel as a whole shrank a bit. It no longer reaches the perimeter marks because we used up some of our yardage broadening seams. It's also not a perfect rectangle any more. This happens on real sails as well. We don't want to go to all the trouble of making a sail with good draft and then find that it now isn't big enough to fit our spars, so something has to give. To fix this, we usually work over a full-sized lofting on the floor (strings, tape, drawn lines, etc. - I use mostly masking tape). When we start laying out the panels, we cut them a bit longer on their ends than the lofting. The broadseaming, basting and sometimes even the panel sewing are all done on these slightly over-sized panels, working over the lofting. Once the seams are basted and the panels connected in their new shape, the whole thing is placed back over the lofting, flattened out as much as possible and the proper edge and corner locations are picked up off of the lofting. That way, our sail has its proper 3-D shape and also measures out the way that it was supposed to in the first place.

Here is the view from the top down of the lug I'm working on at the moment. It's still in three big paneled sections and it's sitting over the lofting, but it's hard to see through it in the picture, so I overlayed red lines on the photo for the perimeter and the green "V" lines which indicate the area where the foot panels get broadseamed. This gives the foot and lower part of the sail a bit of a cup shape and keeps the added foot round from just being a useless flap (that would flap in use). It's tough to see, but all those small panel seams on the bottom section are broadseamed (arrows pointing to them). The entire sail won't fit in the frame, but the seams at the top along the head are aslo broadseamed similarly. With so many panel seams to work with, I can make the broadseams fairly small and subtle.

http://webpages.charter.net/tbradshaw/Broadseams.jpg

If you're starting to get the idea that making a decent sail takes quite a bit more information than the typical one or two page instructions that pepper the internet tend to offer, you're on the right track. The little instruction sheet that Thorne found started OK (with the exception of the 30% draft placement, which just isn't correct) but it left out half of the story - and you can't build a decent functioning sail with only half of the story or half of the required steps. You can add fabric for draft, but then that excess cloth has to be placed properly in order to actually do it - and that requires broadseaming - unless you're a computer......

Computer-cut sails do essentially the same steps - adding round and shaping to move the round to where it can do some good, but they shape differently. Instead of making a 3-D sail with constant-width panels joined by variable-width seams, they use constant-width seams joining variable-width panels. It makes the seaming job easier for untrained labor. Panels are cut with curved edges and even have a "seam-to-here" line drawn on the cloth where the next panel goes. Nearly every seam in these sails will be a simple 1/2"-5/8" overlap at all times. The resulting shape of the sail will be the same, but it pretty much requires a mechanical brain to plot and keep track of all those curves and how they interact. Most of us humans aren't that smart. If you ever buy a sail kit, it will be plotted this way and to assemble it, you just make all the seams the same width everywhere. The pre-curved panels will take care of all the shaping duties.

One last, cool thing about broadseaming, especially on seams that strike the luff of a sail (like on a cross-cut-paneled construction, which will have a bunch of them) is that you also use it to shape the sail's entry curve. Think of it like carving a mahogany, foil-shaped daggerboard. We may know the chord width (fore and aft measurement) of the board, and we may know the maximum desired thickness and where we want that maximum to be on the chord - but how sharp or how dull do we want the leading edge? Some shapes are bound to work better up front than others. Sails are similar, and how sharp or how rounded the entry curve is at the luff will affect the sail's performance.

A sail with a rounded entry curve is generally a good idea. Flat (sharp) entry curves tend to make the steering awfully touchy if your intent is to keep the sail working well as you go through changes in wind speed and angle. They can be very fast, but you had better be right on top of the situation at all times to prevent stalling out. So even high-speed boats like multis, will generally benefit from a more rounded entry curve.

The way we create this rounded entry is by accelerating the rate of our broadseams, flaring them a bit as we approach the very edge of the sail at the luff. Here is a drawing showing two different broadseams and you can see the overlaps where the three panels are joined (I didn't draw the stitching because I was lazy).

http://webpages.charter.net/tbradshaw/ENTRY.jpg

The flared broadseam up top creates a more rounded entry curve for the luff edge and the more we flare those luff broadseams, the rounder the entry gets. We will also add a little bit of flare along foot curves of most sails and the head edges on four-sided sails (gaffs, lugs, etc.) to give those edges a little bit of a cupped shape. The straighter, lower broadseam creates a flatter, less rounded entry, which is less desirable on most sails. We do use some straight broadseams, but most commonly on the leeches of cross-cut sails. We give a couple of the seams at the leech a slight, very straight broadseam maybe 18" long. This helps firm up the leech to prevent stretching-out with age and/or the need to use the dreaded, shape-spoiling leech-line (yuck). We don't want to hook the leech (cupping it) so we don't want any flare in those leech broadseams. We just want to be sure that the leech is nice and firm, and flutter-free. Installing a couple of small leech broadseams is also the proper way to fix a leech that has begun to flutter with age, and it's usually a pretty cheap, simple repair job.

So that's the story on broadseaming. An awful lot of sailmaking is a matter of how many different issues you can keep track of and inter-relate at once and it's one of the big ones that has to be present and accounted for in the big picture if your sail is going to work properly. Hopefully this will give you a little better understanding of what it actually involves.

[DGentry]

Golly, Todd . . . that's a lot of work you, for free, put into your explanations. And I, for one, appreciate it - thanks!

[AJZimm]

Todd,

Let me add my thanks, too.

Great explanations and a great way to teach the rest of us!

[boat fan]

You continue to amaze us Todd.

Very generous of you , thank you!

[htom]

That may be the best explanation of how to go about shaping a sail -- or any non-flat fabric creation -- I've ever read. Thank you, Todd.

[Binnacle Bat]

The above comments require more serious consideration than I can muster after a long day of a long week.

I will say that I have never sailed a boat where the main was too big. I have however sailed plenty of boats with not enough reef points, or who were not easily reefed. Too often "one size fits all" really means one size fits a few people acceptably now and then.

Unless you really like to row, go for the largest sail area you can comfortably spar and handle, and have multiple options for reducing sail. My current boat, by most objective standards, is grossly overcanvassed. With one deep reef tied in, I can still pass "sensibly rigged" boats under full sail. My fractional Marconi sloop has 5 "speeds":
Full sail.
Full sail with one reef in main.
Drop jib with one reef in main.
Two reefs in main, no jib.
Storm sail (old jib with slugs instead of hanks, set in mast slot, sheeted loose footed via spinnaker sheets to quarters.

I wouldn't recommend four sets of reef points in a single standing lug sail, but I would think two a minimum.

In conclusion, sizing sails is a little like politics in Chicago. Don't be afraid of coming on strong, and reef early and often.

Allan

[Todd Bradshaw]

"I wouldn't recommend four sets of reef points in a single standing lug sail, but I would think two a minimum."

Actually, multiple reef lines in a standing lugsail can get pretty problematic. They don't work like the typical slab-style reefs do on most sails (or even those on balanced lugs). Multiple conventional reefs in a standing lug tend to throw the sail's center of effort all over the place (fore and aft) and if you want to keep it from wandering around, you have to do some pretty radical adjustments to the reef lines. I think I've still got a couple examples in my web closet. Yup, check this out. The first reef can still be pretty normal looking, but to keep the CE in about the right spot, especially if your boat only happens to have one sail and you don't want to screw up the helm balance when reefed or have to untie and re-tie the halyard on the yard every time you reef, then the angle of the second reef needs to be tilted substantially. At full sail it looks like some sort of crazy mistake, but once you reef it down it starts to make sense.

http://webpages.charter.net/tbradshaw/SL-reefs.jpg

http://webpages.charter.net/tbradshaw/st-lug-double-reef-006a.jpg

[Pericles]

Hello Todd,

Mikefrommontana started a most interesting thread and noting your observations about sailboard masts in #21, I hope I have something to contribute. Well over 25 years ago I sailed Lasers and sailboards in the River Colne, off Brightlingsea. The first board I tried out was the old luffing machine, the "Windsailer", belonging to a friend and I well remember my first, very painful efforts to regain the safety of the sailing club. That long wooden wishbone boom and the ghastly rag of a sail, that was so hard to control. Even after all these years, the memories are vivid.

The last sailboard I owned was a Klepper S206 with a 6.5 sm sail. On one occasion, I removed the UJ and turned up a chunk of wood to fit between both the Klepper mast and the mast socket of the Laser. I jury rigged the Klepper downhaul (Cunningham on a Laser) to a fairlead screwed to the new base of the mast and set the complete rig into the Laser and secured it. I lashed a pulley to the wishbone, threaded the Laser mainsheet through it and set off.

It was a much more effective rig than I expected and it worked better than the 7.06 sm standard sail, but the mast foot would have benefited from additional reinforcement to cope with the stresses of being plumb upright. Wind forces drive down through the mast foot into a sailboard as the rig is dragged over to windward by the sailboard rider.

After hearing some ominous creaking. I turned back. The next experiment was to use the Klepper rig as a lateen sail. Using only the lower half of the Laser mast, I lashed the Klepper uphaul to the top of the shorter mast and secured a line from the tip of the Klepper rig through the painter fairlead back to the helm position. The wishbone outhaul retained the pulley and I threaded the mainsheet as before. Bearing in mind this was just for fun and the traveller kept fouling, again the Klepper rig worked as a lateen until the uphaul loosened and let go!!!. I should have thought it through a little better, but the rescue boat turned up and that evening, the drinks were on me.

Those were the extent of my experiments. You are correct about the unsuitable flexibility of a sailboard mast when used with other types of sails, but I believe a complete sailboard rig would be rather effective, even without the ability to shorten sail. Just my h'peth worth. I would welcome any and all comments.

[Wayne Poulsen]

I'm building a new mast and spars for the balance lug sail I got from Todd, so I can test both rigs. Can't give a hands-on comparison 'til next fall, but I promise to do it.[/QUOTE]

Hi Chip
Did you consider a bigger/smaller lugsail?
What size/style spars are you building? Will you use the standard mast placement? Ive got GIS and love it. I am considering a lightly built (40kg?) lug rigged Gypsy for singlehanded car topping.
comrades come rally...
Wayne