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Evaluating old sails
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Evaluating old sails
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Evaluating old sails
Gary wrote:
But they do work if you are on a budget. Dacron lasts for decades. Sure. Even a soggy milk carton can go down wind. And blown out old sails will go upwind, sort of. My problem is, I've been spoiled by nice racing rigs for too long. But sailing, in any form, is pure enjoyment... try not to get hung up on details. DSK |
Evaluating old sails
On Sat, 24 Dec 2005 15:12:26 -0500, DSK wrote:
My problem is, I've been spoiled by nice racing rigs for too long. But sailing, in any form, is pure enjoyment... try not to get hung up on details. That's true. The corollary to this, of course, is that a lot of nice racing sails find new homes recut for cruisers at a fraction of the price of new. R. |
Evaluating old sails
rhys,
Yes, but the high tech material does not last as long as Dacron. "rhys" wrote in message ... On Sat, 24 Dec 2005 15:12:26 -0500, DSK wrote: My problem is, I've been spoiled by nice racing rigs for too long. But sailing, in any form, is pure enjoyment... try not to get hung up on details. That's true. The corollary to this, of course, is that a lot of nice racing sails find new homes recut for cruisers at a fraction of the price of new. R. |
Evaluating old sails
SailCare.com says they replace the "resin" that is on new sails and
they restitch whatever needs it. I want to know how to evaluate the shape of a sail so I can decide the most effective way to restitch to renew the shape. I agree, older material is probably not as strong as newer but many sails arre very lightly used. Quite frankly, I simply do not believe what sailmakers say about sails aging just by sitting on a shelf. I also think that a considerable part of the stretch of an older sail is in the stitching and not in th ematerial itself. Even sail material that has stretched probably has not gone beyond the yield point of the material so unless it is actually worn or degraded by UV, I think that most of any loss of strength is in the stitching. So, how does one evaluate the shape of a sail? |
Evaluating old sails
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Evaluating old sails
Rhys,
I agree with your assessment. I need a new suite of sails. Where do I start looking for stretched racing sails? Do you have recommendations? Steve "rhys" wrote in message ... On Sat, 24 Dec 2005 15:12:26 -0500, DSK wrote: My problem is, I've been spoiled by nice racing rigs for too long. But sailing, in any form, is pure enjoyment... try not to get hung up on details. That's true. The corollary to this, of course, is that a lot of nice racing sails find new homes recut for cruisers at a fraction of the price of new. R. |
Evaluating old sails
Merry Christmas to all!
wrote: SailCare.com says they replace the "resin" that is on new sails and they restitch whatever needs it. I want to know how to evaluate the shape of a sail so I can decide the most effective way to restitch to renew the shape. 2 ways sails are shaped, luff round & broadseaming. Luff round is the easiest to change, this is just a big curve built into the front of the sail so that when it is hoisted on a (relatively) straight mast, there is extra material in the middle. Broadseaming is cutting the horizontal edges of the panels in a curve so that the sail will form a 3-D curve when the edges are sewn (or glued) together. .... I agree, older material is probably not as strong as newer but many sails arre very lightly used. Well, between flogging & UV even a "lightly used" sail can be shot. .... Quite frankly, I simply do not believe what sailmakers say about sails aging just by sitting on a shelf. Well, I'm not a sailmaker, and I told you (or tried to). Believe what you want, it happens to be true. ... I also think that a considerable part of the stretch of an older sail is in the stitching and not in th ematerial itself. Certainly the stitching can loosen and give the sail a baggier shape, but the stitches will not stretch. It's strictly a one-way process! ... Even sail material that has stretched probably has not gone beyond the yield point of the material so unless it is actually worn or degraded by UV, I think that most of any loss of strength is in the stitching. So, how does one evaluate the shape of a sail? A couple of ways. One is to lay the sail out in a loft or yard, and fasten the tack, foot, & clew at about waist height with a line on each that can be tightened. Tension the luff first, then lightly haul the foot up. Another is to watch very carefully what the sail looks like when sailing. Looking up from the midpoint of the foot, you should see a nice classic airfoil shape, and you should be able to see definite & consistent change when the "sail shape adjustments" are pulled. A blown-out sail will have one or more- -max draft too far aft (IMHO 55%+ is shot) -draft too deep even when sail is adjusted for max flatness -Lack of response to shape adjustment -Lack or elasticity, ie sail does not return to shape consistently when shape adjustment eased -hard spots in camber, particularly at inner batten ends (I have seen many sails that were described by the owner as "old but still got a lot of life" with upper sections forming a V) By reducing luff round, camber can be reduced but it also shifts aft. If a sail is going to be restitched, the broadseams can be adjusted but most sailmakers dislike doing this. BTW it's not just the stitching, the cloth thru which the stitches are sewn also lose strength. I have personally used sails that have been restitched 4 times, when I took them in for the 5th time the sailmaker said "Y'know Doug, there's not enough cloth here left to sew" and showed me the close network of holes from old stitching. Blown-out sails will affect the boat badly- -inconsistent helm, and excessive weather helm -excessive heeling -little or no acceleration in gusts -poor windward performance, especially pointing -slower Old sails with weakened cloth & stitching are also at much higher risk of shredding under load. I've had this happen a number of times, too. It's a bummer. K. Smith wrote: The modern sail cloth is pretty strong & it will last years & years, Actually, if you expose it to UV all day every day, and put it under strain 24/7 it will last surprisingly short time. .... It's just the boy racers imagining they'll go lots faster with new ones Spoken like a "sailor" who as 1- never won a race and never will, and 2- has never sailed a tuned-up boat with good sails. As to the shape this is not usually a problem Wrong If you want to check it just lay it flat on a floor wrong How the heck are you going to examine a 3 dimensional shape laying it flat on a floor? Oh wait, you don't think shape is ever a problem... Proving once again that usenet is a great source of horribly wrong info. Fresh Breezes- Doug King |
Evaluating old sails
On 24 Dec 2005 21:47:05 -0800, "
wrote: So, how does one evaluate the shape of a sail? ======================================== The objective of sail shape is to maintain a proper foil section, appropriate to the wind strength. The key measurements are depth of the draft, and position of the draft along the chord length. If you have horizontal stripes on your sails you can quantify these metrics by taking pictures upwards from mid-way along the foot of the sail, printing the picture, and measuring graphically. The optimal depth and position of maximum draft varies according to wind speed and can be adjusted to a certain extent with sail controls such as outhaul tension, halyard tension, mast bend, etc. In general, the position of maximum draft should be just forward of the chord center, and the optimal amount of draft decreases as wind strength increases (thus reducing side force). Older sails tend to stretch out of shape in such a way the draft tends to move aft which is an inefficient shape. They also develop wrinkles and uneven shape which are also slow. North sails had some excellent books at one time on sail shape. This is the definitive work on a scientific level but it is expensive and VERY technical: http://tinyurl.com/dg2q4 Here are a couple of others: http://tinyurl.com/curwo http://tinyurl.com/bg3xv |
Evaluating old sails
Contact your local sail makers, the class association group, or your local
yacht club. Most of the serious racers will change sails every year. If you can't find any in your area, go to: http://www.sailingtexas.com/csails.html and look half way down the page. You will see a links to people who sell used sails. "Steve Lusardi" wrote in message ... Rhys, I agree with your assessment. I need a new suite of sails. Where do I start looking for stretched racing sails? Do you have recommendations? Steve "rhys" wrote in message ... On Sat, 24 Dec 2005 15:12:26 -0500, DSK wrote: My problem is, I've been spoiled by nice racing rigs for too long. But sailing, in any form, is pure enjoyment... try not to get hung up on details. That's true. The corollary to this, of course, is that a lot of nice racing sails find new homes recut for cruisers at a fraction of the price of new. R. |
Evaluating old sails
Sorry for jumping in late as I dont have the original posting.
Stitching is easy to replace and redo. The addition of an adhesive tape (PECO tape, etc.) between the broadseams and with an extra row of stitches will solve such weakness cause by UV degeradation of the thread. The killer of dacron sails is UV exposure, the 'whiter' the sail the more rapid the UV degradation. Take a large bladed screw driver and test especially the corners adjacent to the reinforcement pateches ... if the screwdriver blade is easily pushed THROUGH the sail cloth ..... time for new sails. Just about ANY sail has a lifetime of only a 'few hundred hours' if used hard. Racing sails get the ultimate stress (because the crews know HOW to overstress a sail .... therefore in my mind would make a very poor choice for a 'replacment' or recut for cruising. The issue here is 'creep' or permanent deformation of the fibers due to 'oversstretching' of the structure of the cloth - a trulely 'blown-out' sail. Taped luff sails are essentially 'non-adjustable' and once blown out cant be easily re-cut back to good shape unless they are also have their borad seams resewn. A sail with a boltrope (three strand dacron rope in a sleeve at the luff) can usually be brought back to decent shape by simply 'adjusting or easing the rope. What happens in a boltroped sail is that every time you strain the rope it gets shorter and fatter until the sail appear very baggy with draft well aft and the leech hooking to windward ..... most times all thats needed to get such a sail back into serviceable shape is to cut open the heavy stitching that attaches the rope to the sleeve, let the rope slide down a bit into the sleeve and reattach rewsew it with waxed sailtwine Such sails usually are originally 'preloaded' by cutting the rope shorter by about 1 inch for every 10 ft. of luff length. If you have the exact original dimensions of the sail, just check the current luff length versus the original length and reset and resew the bolt rope and the sail will take on proper shape and begin to have 'new life'. This for woven DACRON sails with a boltrope NOT for mylar or other laminated sail material. Why I recommend adjustment of the boltrope is that perhaps 95% of 'cruising' sailors never apply proper halyard tension anyway and in doing so all the time, the boltrope naturally shrinks to a smaller length as a natural course. So if your present mainsail has a very ROUNDED luff shape, seems very full with the draft at or beyond the 50% length of cord and the leech seems to be hooking up to windward .... take the sail to a sailmaker to have the boltrope 'eased/adjusted' ... if this doesnt vastly improve the sails performance, then consider a used or entirely new sail. The shrinking process of the three strand rope is the same process that makes docklines shorter and fatter (and stiffer)... repetetive strain. ..... this is for woven DACRON sails with three strand dacron BOLTROPES inside a sleeve at the luff. hope this helps. In article , DSK wrote: wrote: Last year, I replaced the 22 yr old sails on my 28' S2. Based strictly on stitching inspection, I think the sails had many more years of use but I replaced them because I was convinced by other people that sailing performance would improve. I believe the sailing performance DID improve but cannot be sure because this si so subjective. Well, you should be happy that you *think* sailing performance improved, then. Seriously, did you know know what your boats pointing angles were with the old sails? Did you not have a good idea for what speeds it would attain in given wind conditions & points of sail? What were you doing all the previous times you sailed? ... Now I am skeptical and wonder if sails that are lightly used ( i do not race) really do become significantly stretched and then do not work well. Depends on what you mean by "lightly used." Most resins used in sailcloth (especially pre-1990 or so) get brittle over time even if the sails sit rolled up on a shelf. Heat also degrades the cloth. So if the sails were perfectly rolled & stored, they'd suffer loss of strength & resiliency. UV is also terrible for sails. Considering 'light use,' hoisting & furling sails puts a small amount of wear & tear on the fabric & stitching. Any time the sail flaps or flogs, that's not good for it either. Folding the sail breaks down the resin & fibers & weakens the sail. Dragging the sail across the ground or floor is terrible for it.... in fact I once saw a man bundle a sail up in his arms and unintentionally drag a corner of it across a parking lot. When he went to put it in the back of his station wagon, several sail panels came apart... the stitching had been abraded to nothing. I've had my sails damaged by having stitching catch on dock splinters, it looked like unraveling a knitted sweater. Would having the old sails reconditioned by SailCare make them perform well? Not really. Their treatment does not restore the strength of the cloth, and if they don't re-cut the sail then the shape is not restored. It improves the looks though. And if they restitch places that need it, like batten pockets, this might be more cost-effective than taking it to a sail maker. One method to restore the shape of some sails might be to detach the bolt rope from the bottom of the luff sleeve. The bolt rope often shrinks with age and this puckers the sail into a baggy shape, even if it's not blown out. If the bolt rope is sewn into a sleeve and the stitched thru to hold it in place, sever the thru stitching and let the tack slide down from the end of the bolt rope. You might have to put a slug on the tack so it will stay in the luff groove. It is also possible to restore some shape in the sail by recutting, either at the luff round or one or two broadseams. If you are geting a sail restitched, ask about this. Most non-racing sailors are getting shoved around with crappy sails, and don't know any better. Blown-out sails affect the boats steering and heeling as well as speed & pointing. Fresh Breezes- Doug King |
Evaluating old sails
This probably will help as my old main is a dacron North Sail with a
boltrope. |
Evaluating old sails
DSK wrote:
Merry Christmas to all! wrote: SailCare.com says they replace the "resin" that is on new sails and they restitch whatever needs it. I want to know how to evaluate the shape of a sail so I can decide the most effective way to restitch to renew the shape. 2 ways sails are shaped, luff round & broadseaming. Luff round is the easiest to change, this is just a big curve built into the front of the sail so that when it is hoisted on a (relatively) straight mast, there is extra material in the middle. Broadseaming is cutting the horizontal edges of the panels in a curve so that the sail will form a 3-D curve when the edges are sewn (or glued) together. .... I agree, older material is probably not as strong as newer but many sails arre very lightly used. Well, between flogging & UV even a "lightly used" sail can be shot. .... Quite frankly, I simply do not believe what sailmakers say about sails aging just by sitting on a shelf. Well, I'm not a sailmaker, and I told you (or tried to). Believe what you want, it happens to be true. ... I also think that a considerable part of the stretch of an older sail is in the stitching and not in th ematerial itself. Certainly the stitching can loosen and give the sail a baggier shape, but the stitches will not stretch. It's strictly a one-way process! ... Even sail material that has stretched probably has not gone beyond the yield point of the material so unless it is actually worn or degraded by UV, I think that most of any loss of strength is in the stitching. So, how does one evaluate the shape of a sail? A couple of ways. One is to lay the sail out in a loft or yard, and fasten the tack, foot, & clew at about waist height with a line on each that can be tightened. Tension the luff first, then lightly haul the foot up. Another is to watch very carefully what the sail looks like when sailing. Looking up from the midpoint of the foot, you should see a nice classic airfoil shape, and you should be able to see definite & consistent change when the "sail shape adjustments" are pulled. A blown-out sail will have one or more- -max draft too far aft (IMHO 55%+ is shot) -draft too deep even when sail is adjusted for max flatness -Lack of response to shape adjustment -Lack or elasticity, ie sail does not return to shape consistently when shape adjustment eased -hard spots in camber, particularly at inner batten ends (I have seen many sails that were described by the owner as "old but still got a lot of life" with upper sections forming a V) By reducing luff round, camber can be reduced but it also shifts aft. If a sail is going to be restitched, the broadseams can be adjusted but most sailmakers dislike doing this. BTW it's not just the stitching, the cloth thru which the stitches are sewn also lose strength. I have personally used sails that have been restitched 4 times, when I took them in for the 5th time the sailmaker said "Y'know Doug, there's not enough cloth here left to sew" and showed me the close network of holes from old stitching. Blown-out sails will affect the boat badly- -inconsistent helm, and excessive weather helm -excessive heeling -little or no acceleration in gusts -poor windward performance, especially pointing -slower Old sails with weakened cloth & stitching are also at much higher risk of shredding under load. I've had this happen a number of times, too. It's a bummer. K. Smith wrote: The modern sail cloth is pretty strong & it will last years & years, Actually, if you expose it to UV all day every day, and put it under strain 24/7 it will last surprisingly short time. .... It's just the boy racers imagining they'll go lots faster with new ones Spoken like a "sailor" who as 1- never won a race and never will, and 2- has never sailed a tuned-up boat with good sails. As to the shape this is not usually a problem Wrong If you want to check it just lay it flat on a floor wrong How the heck are you going to examine a 3 dimensional shape laying it flat on a floor? Oh wait, you don't think shape is ever a problem... Proving once again that usenet is a great source of horribly wrong info. Fresh Breezes- Doug King Sorry Doug like most "customers" you have bought the sail maker BS, most sails of the type we're talking about here, are cut lying staked "flat" on the loft floor. (save the super new high tech materials & laminates but they effectively mould the shape into them over a jig) It's easy enough to confirm?? just lay the sail flat on a floor; or measure the panels you'll find most "normal" sails have parallel panels. The shape is induced when a curved edge (the luff or combination of luff & foot) are stretched to varying degrees, in an essentially straight line. (often along a forestay, mast, boom etc.) K |
Evaluating old sails
Sorry Doug like most "customers" you have bought the sail maker BS, most sails of the type we're talking about here, are cut lying staked "flat" on the loft floor. (save the super new high tech materials & laminates but they effectively mould the shape into them over a jig) It's easy enough to confirm?? just lay the sail flat on a floor; or measure the panels you'll find most "normal" sails have parallel panels. The shape is induced when a curved edge (the luff or combination of luff & foot) are stretched to varying degrees, in an essentially straight line. (often along a forestay, mast, boom etc.) K Not! Each seam is cut on a curve and when sewn creates the sail shape, unless you are sailing a sunfish or something. The most obvious example is a spinnaker. Try laying that flat on the floor. None of my sails lay flat except the storm jib. Gaz |
Evaluating old sails
On Sun, 25 Dec 2005 10:59:41 +0100, "Steve Lusardi"
wrote: Rhys, I agree with your assessment. I need a new suite of sails. Where do I start looking for stretched racing sails? Do you have recommendations? Steve I sense sarcasm. I did not say "stretched", and I can only tell you that we have an active race element at my club (we hosted a NOOD event last summer) and that a sail deemed OK but not cutting edge competitive by a guy on a Farr 40 can be the world's most expensive dropcloth OR it can do decent service on a cruiser. I converted a Spectra/Mylar No. 1 from a C&C 34R to my Viking 33, which is a '70s IOR influenced boat with a big J and a small main. I paid about $200 for inspection, minor repair and conversion from tape luff to piston hanks. It replaces a Dacron 153% No. 1 genoa (light) from the late '80s that got shredded in a gust and which would cost me about $2,500-$2,700 Cdn. to replace, new, as Dacron. The recut sail, about three seasons old, equals about 142% and is slightly off the deck at the clew. Otherwise, it fits well and retains to my eye (and I trim on PHRF race boats) a pretty decent shape. It certainly drives the boat well and while heavier than the original light genoa it replaced, seems like a good choice in all but ghosting conditions, for which I have a big asymmetrical, anyway. I am having a main cut back on the leech of the same material and slugs added on the foot to suit my boom for about $200. I have several nearly new Dacron sails (including a superb No. 3 that still "smells" new) that I've culled from guys who've gone to composites mid-season due to the insane one-upmanship you find at the club level when the racers have a bit of cash...like $10-$15K per season...to drop on 25 year old C&Cs and the like. It works for me. Ask a racer with a dimensionally similar boat to your own if he/she stowed a Dacron sail after one season eight years ago and kept it dry. Ask if you can see it. You never know. It's working for me, and I get to budget for new sails and rigging I really have to buy new instead of entire suits of sails all at once. Except for the storm jib. It's 20 years old and still smells new, as does the genoa staysail G R. |
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