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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  

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Interesting.  Based on quotes that I've gotten from North for Dacron sails vs their other technologies and those of competitors, North Dacron panelled sails were generally in the same ballpark as laminate sails from other manufacturers.  That said, I would want to see of these sails provide the same kind of bullet proof reliability as traditional panel sails with woven dacron.  I am a big fan of better sail technology, and I largely think that Dacron ends up being more expensive than better technologies if you really care about shape holding over time.  That said, laminates have intrinsic life span issues built in (glue oxidation in particular, and film breakdown), and I'm guessing that the oxidation issue would be present with this new technology, as the fibers are presumably held in place with glue.  At the end of the day, this definitely looks like a win for shape holding, though I'm skeptical that those thinking that they will all of a sudden have access to molded technology at a reduced cost because their sails are white will be disappointed, as the materials cost shouldn't amount to a huge difference unless comparing to carbon fiber.  

As an interesting side argument for this technology.  The organizers of some classic yachts events have been wringing their hands about the use of modern sails in these events.  Some folks get all bunged up when they see black sails, and they attribute all success to people having these sails, even when the results either suggest otherwise, or the sailors lodging complaints can barely sail upwind to begin with, so focus their efforts on personal improvement by attacking rating systems or the hardware of others.  Given that these sails are made of Dacron, which for some reason is seen as a natural fiber by this bozos, I would see this as a great way to appease the classic yacht dilettantes, and not throw money away by purchasing woven racing sails that lose their shape a quarter of the way through the season. .    

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I attended an evening with Ken Read and Jeff Johnstone in Annapolis some weeks ago, where Ken announced this product.

I feel that he set the bar pretty high for North- A cost comparable to Dacron, a long service life and durability and racing sail performance.  I need a new main anyway, so I'm very curious about this.  Regarding the short shape-holding time of Dacron- I feel that it depends on how you treat them. I think you can get a lot more than half a season out of them.

That's kind of a non-sequitor though, as these sails are targeted at cruisers, not racer.

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I get what you're saying completely.  As a racer, I obviously appreciate reliable sail shape.  I also really enjoy this as a cruiser too.  I have a new main coming this season after having to go last season with my very old North dacron main.  I had to do this because my previous main, a Cuben Fiber sail basically failed instantaneously.  That sail, up to that point had a terrific flying shape.  I am still grateful to have an old blown out dacron sail that is essentially indestructible, but sailing with it vs my cuben sail is a completely different experience, particularly in light air and close hauled in any breeze.  My feeling is that the cruising benefits of good sail shape are largely underappreciated within the cruising community.  

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As someone who straddles the line between the two communities, I totally appreciate good sail shape. :)

That's always been my gripe with high tech sails- The "failure mode."  They often fail as your Cuben sail did, where Dacron sails will at least get you home.  Of course, the failure mode of Dacron is very insidious. It's slow and escapes your notice until you finally look up one day and say "Wow, that looks terrible! No wonder I can't get upwind!"

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I asked my sailmaker about the likely  failure mode of my laminate main. He said, "These sails just get lumpy." Of course he knows I spend approximately  zero time in winds  above 20kts.

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That https://northsails.com/sailing/3di-nordac page describes an interesting new technology, but it is very hypey.  It would be much more useful if it gave some clearer comparison with other technologies.

It says "3Di NORDAC marries patented 3Di shape holding technology with the toughness and affordability of polyester sails", which kinda implies that it holds shape as well as a3Di sails.  That is obviously not the case, so where does NORDAC fall on the shape-holding spectrum?

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it sounds like 3di but with dacron fibers instead of aramid or carbon... 

 

....whats the difference between dacron and aramid? 

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It's probably decent, but not as stiff overall as carbon, aramid or dyneema materials.  The fact that the yarns are now truly oriented along predicted load paths will go a very long way towards shape holding, and likely be a dramatic improvement on dacron sails.  All of that said, I still stand by my original point that you should not expect these sails to be bulletproof like woven dacron sails, as they are now essentially polyester laminates all relying on the same glues that eventually suffer in a catastrophic failure mode.  On the other hand, you should expect many more seasons of decent sail shape than you would with a woven sail, particularly if you opt to go with full battens.

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4 minutes ago, mustang__1 said:

it sounds like 3di but with dacron fibers instead of aramid or carbon... 

 

....whats the difference between dacron and aramid? 

Aramid is the generic name for Kevlar.  Dacron is a trade name for Polyethylene terephthalate

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This sail is a kind of throwback to the early laminated sails which were made from light, loosely woven dacron cloth bonded to a mylar film. The sails tended to last two summers for racing and two more for beer can. The drop in performance was usually caused by old age in the dacron and UV causing the mylar to fracture. These sails will probably perform like those.

The main technological advance is that the Nordac sails will be both lighter and seam free. They also might gain some benefit from a layer of taffeta protecting the tapes from UV damage. I don't know the exact proposed layup.

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From the North site:

3Di™ is a unique, patented sailmaking technology that produces the world’s fastest and most durable sails. 3Di sails mirror the balanced load bearing and shape holding of a rigid airfoil wing. They are composed of ultra-thin unidirectional spread filament tapes, pre-impregnated with thermoset adhesive, arranged in a complex multiple-axis array, and three-dimensionally molded into a one-piece, flexible composite membrane.

There's no mylar, and I imagine the "thermoset adhesive" resin is durable and won't mildew like laminate glues. Another North quote:

The resin is a thermo plastic not an epoxy but it is very much the same as a boat building pre-Preg resin where it’s live, there is a curing and catalyst stage inside of it.

Dacron is quite UV resistant, and the "tapes" are themselves Dacron. No need for taffeta.

3Di sails haved proved themselves bulletproof. This is just a 3Di made with Dacron.

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Ajax,

With a woven dacron sail you lose shape due to two main mechanisms. #1 the weave deforms - eg what should be a 0/90 degree fiber orientation gets pulled by off axis loads to some other set of angles, thus deforming the cloth, and #2 the polyester fibers themselves stretch.

3di is not a weave. Tapes with unidirectional fibers are laid in orientations chosen by the sail designer.  This 'should be' more resistant to the first sort of deformation if the designer gets it correct, but the off axis loads can still deform 3di if the designer does not get the fibers oriented correctly.  I presume in an 'inexpensive' dacron 3di (inexpensive compared to other north products) there will be less designer time built in - with computer layout that will probably not hurt the fiber orientation too much - but I would expect there will be some learning curve, especially around details like reef points.  In a dacron mylar laminate, the mylar itself prevents off-axis deformantion - in 3di it will be a combination of the tape layout and the adhesive (see comments about adhesive below).

The fundamental dacron fiber stretch (on axis) should be similar to woven sails - particularly to the radial cut ones. It will not change.

Woven sails will survive as 'functional white triangles' for a long long time even with impaired shape - 15 or 20 years in many cases.  With 3di the structure will be held together entirely by thermoset adhesive.  North does NOT have a lot of experience with the ultimate lifespan of this adhesive in the 10's of years range (there will be fatigue and environmental issues they really have not experienced much yet), as most of their 3di's to date have been racing sails with relatively short lifespans (3 years would be a pretty long racing sail life span).   This may not be a concern if you plan to replace sails on say a 5 year time horizon, but could be if you 'expect' 10 or 15 years from 'dacron' sails. North had adhesive and tape layout 'issues' when they first launched 3DI, and I would sort of expect them to go thru similar teething issues with dacron tapes (but these teething issues will take longer to play out). Ultimately I would expect them to be longer lasting than typical dacron mylar laminate - but initially they may or may not be.

I might note that 3di's do in fact have seams.  Their panels are laid up on flat tables, broad seamed, and then glued together (on the mold).  usually these seams are reliable, but north has occasionally had QA problems and the seams have come apart.

 

 

 

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Evans, you mentioned the adhesives...that seems to be the issue that would concern me the most ( I was working in a sail loft back when we still sewed broadseams together on a machine around 1992), but if they can get the adhesives to hold, it might be a good product..I also assume there are adhesives impregnated in the fibres themselves like 3Dl and 3Di?? Is there any kind of encapsulating film to hold everything together? My stepfather has a 15 year old tri-radial Pentax AP#1 on a Tartan 3000 built by Quantum, and I will admit the shape is as round as the moon, but the glued broadseams and the sail itself are still intact. That sail probably saw 6 or 7 seasons of hard racing, and probably 5 races in the last 7 years.

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2 hours ago, estarzinger said:

Ajax,

With a woven dacron sail you lose shape due to two main mechanisms. #1 the weave deforms - eg what should be a 0/90 degree fiber orientation gets pulled by off axis loads to some other set of angles, thus deforming the cloth, and #2 the polyester fibers themselves stretch.

3di is not a weave. Tapes with unidirectional fibers are laid in orientations chosen by the sail designer.  This 'should be' more resistant to the first sort of deformation if the designer gets it correct, but the off axis loads can still deform 3di if the designer does not get the fibers oriented correctly.  I presume in an 'inexpensive' dacron 3di (inexpensive compared to other north products) there will be less designer time built in - with computer layout that will probably not hurt the fiber orientation too much - but I would expect there will be some learning curve, especially around details like reef points.  In a dacron mylar laminate, the mylar itself prevents off-axis deformantion - in 3di it will be a combination of the tape layout and the adhesive (see comments about adhesive below).

The fundamental dacron fiber stretch (on axis) should be similar to woven sails - particularly to the radial cut ones. It will not change.

Woven sails will survive as 'functional white triangles' for a long long time even with impaired shape - 15 or 20 years in many cases.  With 3di the structure will be held together entirely by thermoset adhesive.  North does NOT have a lot of experience with the ultimate lifespan of this adhesive in the 10's of years range (there will be fatigue and environmental issues they really have not experienced much yet), as most of their 3di's to date have been racing sails with relatively short lifespans (3 years would be a pretty long racing sail life span).   This may not be a concern if you plan to replace sails on say a 5 year time horizon, but could be if you 'expect' 10 or 15 years from 'dacron' sails. North had adhesive and tape layout 'issues' when they first launched 3DI, and I would sort of expect them to go thru similar teething issues with dacron tapes (but these teething issues will take longer to play out). Ultimately I would expect them to be longer lasting than typical dacron mylar laminate - but initially they may or may not be.

I might note that 3di's do in fact have seams.  Their panels are laid up on flat tables, broad seamed, and then glued together (on the mold).  usually these seams are reliable, but north has occasionally had QA problems and the seams have come apart.

 

 

 

IMG_3355.thumb.JPG.923857d120d1eb1556767bdc106c9ff5.JPG

How is the glue looking on this North sail?  Shape?  How many more seasons can I get out of it?

Should I go Nordac for my Nordic?

Edit:  Gotta love the swoopy leach from the second reef point to the third batten.

(A loft blessed this for the crossing, but I woke up for my watch one day and saw this sickening sight.  The crew doesn't know what happened.  BUT, this eyesore took us 1600 NM, double reefed, and still gave us 8.5 to 9 kts. on most days.  I think it's time to retire it.)

 

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Since the cat is now out of the bag on these I guess I can say "I'll tell ya on  (about)  June 15th."

We ordered a 142% for our Ranger 26. Originally we were going to get the radian but the price wasn't that much difference (We also got a pretty nice discount for being willing to be a test subject, well kinda) 

For us it looks to be a perfect match. I am rebuilding the boat to be a true racer/cruiser for the lake we are on and the Puget Sound. Efficient but comfortable.  I'm not really sure I can answer too many questions on them until I get my hands on it. 

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That mildew in 46664 above is the reason I'll never get a laminate sail again. Looks like shit and there's no effective way to prevent it.

Does anyone know how the "thermoset adhesive" differs from the glue used in laminate sails? North's marketing claim suggests we should think of the glue the same way we think of resins used in hull laminates. We don't worry about hull failure through resins breaking down, at least if there were no glaring problems with construction.

 

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E-

Thanks for the explanation of how Dacron degrades. :)

I was hoping for 10 years of careful use out of this new type of sail. I'm not necessarily going to wait for a 10 year test sample before I buy one but I don't think I'll be a first-adopter either. I'm glad that ordkhntr is our test subject! :)

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9 hours ago, Hike, Bitches! said:

I also assume there are adhesives impregnated in the fibres themselves like 3Dl and 3Di?? Is there any kind of encapsulating film to hold everything together? 

3di is a three stage process.  (1) You have a tape making machine, which takes yarns and runs them thru rollers to spread them out very thin, then thru an adhesive bath, then lays them on a paper backer (this holds the tape together while preventing it from sticking to itself) and spools them up. #2 you have a tape laying machine (North calls it a plotter), which takes the spools of tape and lays them out on a flat table into sections of the sail per the sail makers design, peeling the paper backer off. And #3 they roll up those sections, carry them over to the sail mold, lay them in place lining up the broad seams on the mold and then heat cure them.

There is no film anywhere in the finished process.

It is a capital intensive process.  The tape laying machines in particular are quite slow. I am sort of guessing that North has excess capacity atm. I am curious whether these dacron 3di will be built in their factory in sri Lanka or Minden. I'm guessing sri lanka - but if there is a ton of excess capacity in minden it might be there - Minden was sized for americas cup peak time back when they used 100's of sails and they only using a couple now.

as an aside, I was business partners with the 2 swiss engineers who invented/developed this process.

43 minutes ago, kdh said:

Does anyone know how the "thermoset adhesive" differs from the glue used in laminate sails? North's marketing claim suggests we should think of the glue the same way we think of resins used in hull laminates. We don't worry about hull failure through resins breaking down, at least if there were no glaring problems with construction.

 

KDH, you do need to take North's "marketing claims" with a large dose of salt.  They are notorious for 'stretching the truth". Do you remember back in the 3DL hayday when North claimed a sail would be no good unless it had corner to corner continuous fibers - and that whole point just instantly disappeared from their marketing when they rolled out 3di because it does not use continuous fibers. And their claim of "seamless" is just a plain fib - it has seams - way fewer than a paneled woven sail but still has them.

Your glue question is a bit complex, because there are several quite different glue systems in use in laminate sails. But north's claim is a bit BS - In boat construction you mostly use 2 part adhesives that chemically change (both polyester and epoxy do) when they cure.  North is using a thermoset, which does not fundamentally change - you could heat it back up and it would 'uncure'.  That is what happened to a generation of 3dl sails - the thermoset adhesive had too low a temp set point and it would uncure in the tropics.  The difficulty is that thermosets with higher heat points tend to be brittle, which causes a different set of problems (quantum experienced some of these). So it is a design balance. North has learned quite a bit since 3dl and (hopefully) has that balance better figured out.

17 hours ago, kdh said:

No need for taffeta.

They actually can/do put taffeta on 3di's - customer's choice.

8 hours ago, Whisper said:

 

How is the glue looking on this North sail?

 

just guessing - 3dl, vectran fibers, on a tropical passage? pretty classic failure mode if so - taffeta has been UV cooked and glue heat softened a bit and then come apart exactly like that. I had it happen to one of my mainsails about 500 miles from Hawaii - we sailed in with a huge hole in the middle of the sail, but the strings were actually keeping sort of decent shape across the rest of the sail.

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Evans, the glue issues as you describe them are thought-worthy. I guess "a laminate without the mylar" is not hugely far off. When I read this in an article quoted from someone at North my bullshit meter registered a bit:

The resin is a thermo plastic not an epoxy but it is very much the same as a boat building pre-Preg resin where it’s live, there is a curing and catalyst stage inside of it.

I guess the "catalyst" is heat.

I suppose taffeta would be used to protect the glue, not the Dacron.

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Same old line from big blue.  Its not seamless and its a laminate sail.  If you are a cruiser and want a durable proven product Dacron is the way to go.

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We still don't know whether the so called " thermoset adhesive " can handle long term UV exposure. It might well turn brittle and start to fracture as well as lose contact with the fibers. Based on what we know so far this type of sail seems best suited to day sailors and club racers. It might be best for any cruiser buying this type of sail to request the addition of taffeta, if only to extend the sail's lifespan.

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There is an important distinction between "thermoplastic" and "thermoset:" 

ther·mo·plas·tic
CHEMISTRY
denoting substances (especially synthetic resins) that become plastic on heating and harden on cooling and are able to repeat these processes.
 
A Thermosetting resin is a prepolymer in a soft solid or viscous liquid state that changes irreversibly into an infusible, insoluble polymer network by curing.
 
It seems "thermoset adhesive" is just wrong if it's a thermoplastic. 

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To me the fundamental question is the method of holding the fibers together.

Obviously a mechanical weave is the "belt and suspenders" approach but when any stiffening resin used fails it's highly susceptible to shape issues.

With 3Di we rely purely on the resin to hold the fibers together.

If we want ultimate reliability a weave is favored. If a bad shape is as bad as nothing at all then we might as well put our faith in the resin and enjoy the design advantages that come with that.

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^^  for me, the key question is the cost/economy of this process.

I suspect after a bit of teething these sails will be functionally fine - not the best thing since sliced bread, and not as terrific as North's marketing claims, but functionally a bit better than other Dacron alternatives.

However sailors buy dacron to be economical.

Paneled sails do require some significant sewing labor, while the 3di process is much more capital intensive.  The pure variable cost of the 3di process is not so high (the backing paper was a surprisingly high fraction of the variable cost), so if you price these out without much capital allocation (to use up spare wasted excess capacity) then they might be economical.

I dont remember in the variable cost how much was fiber cost - but when you look at the total process, for most of it, it does not matter to the costs if you are running high mod fibers or Dacron thru it. Makes you wonder if, long term, dacron is really an efficient way to use the capital, unless you just have a lot of spare capacity sitting around.

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I'm all about aesthetics and am a coastal cruising sailor.

I like Dacron because it's white. I like 3Di because it produces a good-looking, easily handled sail.

Of course any sailor appreciates good shape.

If a sail blows out I'll motor home and ask North for a new one. :)

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They do have some 'aesthetic' extra options for 3di, and I suspect you would like them.

btw . . . regarding adhesive . . . . we did '3di' even with epoxy pre-preg - look up "Thin Ply Technology' - to make rigid composites.  We made some wing skins that way.

But for soft sails there is this trade-off I mentioned above between 'stability' and 'brittleness' (more stable tends to equal more brittle). 

There is also an issue with laying the 3di panels over high Gaussian curvature.  They dont conform very well - fibers tend to get kinked - may not be a big issue with dacron but was with high mod fibers..

 

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32 minutes ago, estarzinger said:

There is also an issue with laying the 3di panels over high Gaussian curvature.  They dont conform very well - fibers tend to get kinked - may not be a big issue with dacron but was with high mod fibers..

 

Is that why some classes still tend to go with 3dl for their lighter air headsails with more shaping?
(Farr 40, Melges 32...)

 

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^^ I would guess that has more to do with weight.  3DL can be made (significantly) lighter than 3DI for lowish load applications.

Cuben Fiber is another alternative for those sorts of sails - it is spread filament like 3di, but with mylar base.

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After interviewing several sailmakers for the four carbon cutters project we went with North. The Seattle North loft made a very strong presentation. The client made the decision and everyone was comfortable with it. I will get a set of sail specs and post them here. For me it was paramount that the boats get the best sails possible.

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Bob Perry: What tech are they using for the sails on that project?

It'll be interesting to see after 5+ years how this holds up compared to a radial dacron sail made with radial specific cloth like Warpdrive or Nordac radial.  

It seems like it is a tradeoff of getting slightly better load path through the fabric by being able to optimize that on very small sections of cloth vs using stitching instead of adhesives to hold the sail together.

I just ordered a Warpdrive sail for our cruising/delivery #2 and I'm still feeling pretty good about that decision.  This sail wasn't cheaper than cheap laminates, but I think dacron is a good choice for a sail that will get more abuse when the boat is short handed.

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11 minutes ago, Alex W said:

Bob Perry: What tech are they using for the sails on that project?

It'll be interesting to see after 5+ years how this holds up compared to a radial dacron sail made with radial specific cloth like Warpdrive or Nordac radial.  

It seems like it is a tradeoff of getting slightly better load path through the fabric by being able to optimize that on very small sections of cloth vs using stitching instead of adhesives to hold the sail together.

I just ordered a Warpdrive sail for our cruising/delivery #2 and I'm still feeling pretty good about that decision.  This sail wasn't cheaper than cheap laminates, but I think dacron is a good choice for a sail that will get more abuse when the boat is short handed.

 

You are exactly right on that last sentence. I eschewed Andy Evans' advice on that, and really fucked up a good, kevlar jib when racing singlehanded. I now have a tri-radial, Dacron sail. It's done me well so far.

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Alex:

I'm waiting for an email from North with the exact specs for the inventory. It was only recently finalized and if I post it I don't want t make a mistake. I know how you guys are.

I'll post i as soon as I get it.

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3 hours ago, Bob Perry said:

After interviewing several sailmakers for the four carbon cutters project we went with North. The Seattle North loft made a very strong presentation. The client made the decision and everyone was comfortable with it. I will get a set of sail specs and post them here. For me it was paramount that the boats get the best sails possible.

 

The correct answer to this question is rarely clear because it depends on the client's chosen trade off between performance, durability and cool factor.

I'm not a fan of North for cruising gear.

 

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There's alway HydraNet for a white Dyneema sewn sail.  Loved my last one, but sold the boat.

I want the best sail for the $$, not worried about a blue logo.  I'll get quotes for the North and dyneema sails.

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2 hours ago, Alex W said:

It'll be interesting to see after 5+ years how this holds up compared to a radial dacron sail made with radial specific cloth like Warpdrive or Nordac radial.  

It seems like it is a tradeoff of getting slightly better load path through the fabric by being able to optimize that on very small sections of cloth vs using stitching instead of adhesives to hold the sail together.

Agreed.

I have 5 seasons on my Nordac radial sails. They've delivered beyond expectations. No mildew. Good shape.

I think 3Di Nordac is a reasonable alternative for my next sails.

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16 hours ago, estarzinger said:

3di is a three stage process.  (1) You have a tape making machine, which takes yarns and runs them thru rollers to spread them out very thin, then thru an adhesive bath, then lays them on a paper backer (this holds the tape together while preventing it from sticking to itself) and spools them up. #2 you have a tape laying machine (North calls it a plotter), which takes the spools of tape and lays them out on a flat table into sections of the sail per the sail makers design, peeling the paper backer off. And #3 they roll up those sections, carry them over to the sail mold, lay them in place lining up the broad seams on the mold and then heat cure them.

There is no film anywhere in the finished process.

It is a capital intensive process.  The tape laying machines in particular are quite slow. I am sort of guessing that North has excess capacity atm. I am curious whether these dacron 3di will be built in their factory in sri Lanka or Minden. I'm guessing sri lanka - but if there is a ton of excess capacity in minden it might be there - Minden was sized for americas cup peak time back when they used 100's of sails and they only using a couple now.

as an aside, I was business partners with the 2 swiss engineers who invented/developed this process.

KDH, you do need to take North's "marketing claims" with a large dose of salt.  They are notorious for 'stretching the truth". Do you remember back in the 3DL hayday when North claimed a sail would be no good unless it had corner to corner continuous fibers - and that whole point just instantly disappeared from their marketing when they rolled out 3di because it does not use continuous fibers. And their claim of "seamless" is just a plain fib - it has seams - way fewer than a paneled woven sail but still has them.

Your glue question is a bit complex, because there are several quite different glue systems in use in laminate sails. But north's claim is a bit BS - In boat construction you mostly use 2 part adhesives that chemically change (both polyester and epoxy do) when they cure.  North is using a thermoset, which does not fundamentally change - you could heat it back up and it would 'uncure'.  That is what happened to a generation of 3dl sails - the thermoset adhesive had too low a temp set point and it would uncure in the tropics.  The difficulty is that thermosets with higher heat points tend to be brittle, which causes a different set of problems (quantum experienced some of these). So it is a design balance. North has learned quite a bit since 3dl and (hopefully) has that balance better figured out.

They actually can/do put taffeta on 3di's - customer's choice.

just guessing - 3dl, vectran fibers, on a tropical passage? pretty classic failure mode if so - taffeta has been UV cooked and glue heat softened a bit and then come apart exactly like that. I had it happen to one of my mainsails about 500 miles from Hawaii - we sailed in with a huge hole in the middle of the sail, but the strings were actually keeping sort of decent shape across the rest of the sail.

I'm loving this thread and I'm learning a lot.

Yes, I was heading for Hawaii--but this was late November, 900 miles off Baja in pretty cold temps  I wore sweatshirts under my foulies during daylight--more at night.  But the sail was old (last serviced in 2005, but I don't know when it was built) yet a loft told me it was dirty but fine for the crossing.

As a shorthanded cruising crew, I'm concerned about weight (for my wife to hoist, lol) as much as shapeholding ability and cost.  I realize I'm the first to confront this dilemma (lol).

I need to spend $$$ now and I'm trying to minimize the regrets I'll have in a year or two.  Please drop a few more hints.

The next 5 years will be hopping islands in Hawaii, and then excusions to Tahiti when my wife can take more time off work.  Probably no racing.

 

 

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7 hours ago, Whisper said:

As a shorthanded cruising crew, I'm concerned about weight (for my wife to hoist, lol) as much as shapeholding ability and cost. .

yea, had similar situation/objective when we got our last main.  Beth could hoist the 3dl, but when we moved away from 3dl everything else was noticably heavier and she had trouble hoisting above the 2nd spreaders. I put on a 2:1 halyard, which solved that problem - hoists a bit slower but she was confident she could again handle things on her watch.  That was back in the earlier days with 3di and they were building it heavy to compensate for teething issues.  I believe they are now lighter than they were, but dont think they have gotten back down to 3dl weights (damn getting actual true bag weights from sail makers is hard).

kdh, just two small further things for you on 3di . . . #1 it has a very different "hand"/feel - more "plastic", less "fabric" - never bothered me, but "feel" is an important part of some people's aesthetics.  #2 I seem to remember that you have a furling main (?) . . . . when I last looked at 3di the corners were very very stiff.  They had a way to get them to work with furling systems, but it was not ideal. They may well have sorted this out, and your sails probably less loaded than mine were - but something to try to get an honest assessment on.  

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Pretty tough to beat cross cut dacron with full battens for a cruiser.  It lasts a long time and will generally be 1/2 to 1/3 the price of the top end sails.

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Thanks, Estar. You're right, I have boom furling. Will ask those questions when the time comes. It's so easy to get starry-eyed with new products.

Speaking of new products, Joli, have you done anything about your electronics? I still have my 2005 vintage gear. I thought my old-school magnetron radar kicked it last season but it was just the cable.

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After much deliberation my client for the four carbon cutters ordered these sails.

Main, genoa and staysail are built from Tour UltraXC Norlam NLUC320

Gennaker is 1.5 oz. nylon

Storm sails are  Polyester High Visibility Storm Orange

No good Monday morning this inventory. It's made.

Sail_zpsg4w0dtpt.jpg

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They will be fine sails Bob.

But it is a bit of an odd choice. Does not play to North's technological strengths. (I'm surprised that north won given the end choice, must have had a terrific sales guy).

The working sail fabric is a somewhat generic high mod laminate aimed primarily at bigger boats than your cutters.

The gennaker fabric is bog standard - and I would guess the sailmaker really wanted to make it from .75oz rather than 1.5.

I guess I would have said these were 'low risk' sails, rather than 'best sails possible'.

New sails are (almost) always a delight.

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Yes, you are correct. North has a very polished sales presentation and a strong Seattle loft. That was a big factor in choosing North.

If he does not like the sails he can change the order on the next three sets. That would be fun. I'd like that.

I have no doubt the sails chosen will be great sails.

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14 minutes ago, Bob Perry said:

he can change the order on the next three sets. That would be fun. I'd like that.

I agree, that would be fun. If he used the cutters somewhat evenly, I would be really curious to see how various options aged. Could be a great contribution to the knowledge base - if client is interested.

I have no doubt the sails chosen will be great sails.

Yea, agreed, as I said, I'm sure they will be just fine. It's not like they will be doing the Vendee or AC.

 

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A four identical boat test with different sails would be very instructive and fun. Not sure I can sell that idea. Let's wait and see how the first set works out.

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11 hours ago, Max Rockatansky said:

I'm gonna second the suggestion re: Hydranet. I have triradial jib and main and three years into them, including some racing, they are doing very well.

Anyone else tried a Hydranet sail? Anyone on a square head? About half the people I talk to think the material is great, the other half crap. 

I'm with KDH, laminate sails just don't look very good when they turn a stinking black/green from mold. I have found a way to prevent it: remove, dry, fold, and store indoors every time you leave the boat for a couple of days. It isn't a practical solution except on a dinghy. 

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+100 for radial hydranet

-100 for cross cut hydranet

Haven't seen any square tops, but I've seen some used by very abusive owners that lasted way longer and looked way better than they should have given their treatment.

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Ok, for the 4 cutters - here's what we need for the working sail 'test':

3di endurance 760 white - "best available sails"
TourUltra - "good laminate"
Hydranet radial - "good radial panel"
NorDac crosscut - "baseline"

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4 hours ago, DDW said:

Anyone else tried a Hydranet sail? Anyone on a square head? About half the people I talk to think the material is great, the other half crap. 

I'm with KDH, laminate sails just don't look very good when they turn a stinking black/green from mold. I have found a way to prevent it: remove, dry, fold, and store indoors every time you leave the boat for a couple of days. It isn't a practical solution except on a dinghy. 

We did that with our racing 3dl sails. Our no4, which had been up less than 5 times, essentially aged in the bag. Hoist number 6 of its life saw plastic confetti blowing downwind. 3dl was atrocious in the tropics

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10 hours ago, estarzinger said:

Ok, for the 4 cutters - here's what we need for the working sail 'test':

3di endurance 760 white - "best available sails"
TourUltra - "good laminate"
Hydranet radial - "good radial panel"
NorDac crosscut - "baseline"

Why do a test on one brand?  Why not one Doyle, one Quantum and one Hood as well.  All have reputable Cruising products.

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Hydranet, as a weave made from spun yarns, will have much more stretch than even a Dacron 3Di, which is made with filaments. The spinning and weaving build in a lot of stretch.

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On 5/18/2017 at 10:40 PM, sailman said:

Same old line from big blue.  Its not seamless and its a laminate sail.  If you are a cruiser and want a durable proven product Dacron is the way to go.

I think Dacron is a bit stretchy once you get to larger boats though, which is why we've been using Hydranet.

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1 hour ago, sailman said:

Why do a test on one brand?  Why not one Doyle, one Quantum and one Hood as well.  All have reputable Cruising products.

because Dacron cloth wise, you'll most likely end up with Contender sailcloth or Dimension Polyant. so that leaves that 1)you can test the sail  shape of the different sailmakers for the same boat, or 2) test several weights of cloth for the same boat or 3) get a same set of sails made from both producers.

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On 5/19/2017 at 10:01 PM, Max Rockatansky said:

I'm gonna second the suggestion re: Hydranet. I have triradial jib and main and three years into them, including some racing, they are doing very well.

We put a Hydranet Crosscut main and Genoa on our boat. The Main is ten years old and has taken us from New England to Australia over the last five years. We take delivery of a Hydranet Radial main in June sometime. The Geno is six years old and has more life in it still.

The crosscut clot is supposed to be stretchier than the radial, and our main has gotten more full. We could have recut it and got quotes to do so, but with the upwind sailing we may be doing in the next 2-3 years we didn't want to depend on that.

We've been very happy with the sails so far. Our biggest problem with the main (outside of unavoidable stretching over time) was the stupid threads and webbing holding the clew on getting eaten by UV. We ripped that off once leaving Trinidad (threads) and on the way to Bora Bora from Tahiti (webbing). And the UV covers on the edges have worn more quickly than the sail and needed replacing.

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48 minutes ago, kdh said:

Hydranet, as a weave made from spun yarns, will have much more stretch than even a Dacron 3Di, which is made with filaments. The spinning and weaving build in a lot of stretch.

Hydranet has aramid fibers woven into it, not just spun. It took ten years and a lot of ocean miles to stretch our main to the point it annoyed me. And HN crosscut is stretchier than HN radial.

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19 minutes ago, B.J. Porter said:

Hydranet has aramid fibers woven into it, not just spun. It took ten years and a lot of ocean miles to stretch our main to the point it annoyed me. And HN crosscut is stretchier than HN radial.

*spectra

 

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BJP: wonder whether the maker could stitch the clews with PTFE? Might solve the stitching failure. And of course UV covers are designed to be sacrificial, you surely can't complain about that?

 

My understanding of Dacron vs Hydranet is that the longevity overall is similar, but whereas Dacron stretches in a year, HN holds shape for most of its life. 

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DDW,  I've got a full batten, square top Hydranet radial main.  It's still too new to tell how it will last but looks good for now....

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58 minutes ago, Max Rockatansky said:

My understanding of Dacron vs Hydranet is that the longevity overall is similar, but whereas Dacron stretches in a year, HN holds shape for most of its life. 

DP loves that people think this way. But the reality from DP's own marketing literature:

DIMENSION-POLYANT’s Hydra Net® radial styles combine the durability of a woven polyester base with a ripstop of Ultra-PE. The resulting fabric is higher in tear strength and, combined with the strength of the ripstop, stronger over the life of the sail than any woven polyester.

A "ripstop?" Seems to be an admission that the spectra is never under load. Dacron shrinks when it's heat set and spectra doesn't, hence it's a ripstop. Further, the Dacron can't be properly heat set because the spectra would melt. There's a reason WarpDrive and North Radian cloth are pure (properly heat set) polyester. The benefit of all of these cloths is the warp-oriented weave. 

But they're all still a weave made from spun yarn and as such stretch is built in.

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Veeger, who made it? Are you still in Cap Sante? Looked around last week, didn't see you...

Some sailmakers have told me they have had bad experiences with Hydranet, "just a stretchy dacron". Unfortunately many of the anecdotes come without enough color: Radial vs. cross cut, treatment of sail, etc. DP says that the radial version of the cloth has much more Spectra (or Dyneema) than the cross cut. Now there is also Contender's version, Fibercon Pro Hybrid. I would like to know the % dyneema in each. Anybody have that info? Maybe I will need to do my own tests.

I will agree that a laminated or glued fiber string sail should be stronger, lighter, and less stretchy. The lighter part begins to diminish when the required additions for cruising are added up: stackpack, full battens, taffeta on both sides, etc. My string sail main weighs 165 lbs in the bag, add another 60 lbs or so for battens when you hoist it. Too heavy to pick up without a crane, so what would another 20 lbs matter?

I have put a lot of effort into trying to keep these string sails from molding, unsuccessfully. I won't have them again till they figure out a solution. 

 

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7 hours ago, Max Rockatansky said:

BJP: wonder whether the maker could stitch the clews with PTFE? Might solve the stitching failure. And of course UV covers are designed to be sacrificial, you surely can't complain about that?

 

My understanding of Dacron vs Hydranet is that the longevity overall is similar, but whereas Dacron stretches in a year, HN holds shape for most of its life. 

I can't complain too much, no. I've spent a lot of time in the sun.

I'm not sure what options there are, but I know there is a UV coating we used to dip our stripped halyards in back when I had a race boat.

For us, the consideration also is that above a certain level of loading, Dacron is going to stretch faster. So with the size of our boat it's not an optimal choice.

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1 hour ago, DDW said:

Veeger, who made it? Are you still in Cap Sante? Looked around last week, didn't see you...

Some sailmakers have told me they have had bad experiences with Hydranet, "just a stretchy dacron". Unfortunately many of the anecdotes come without enough color: Radial vs. cross cut, treatment of sail, etc. DP says that the radial version of the cloth has much more Spectra (or Dyneema) than the cross cut. Now there is also Contender's version, Fibercon Pro Hybrid. I would like to know the % dyneema in each. Anybody have that info? Maybe I will need to do my own tests.

I will agree that a laminated or glued fiber string sail should be stronger, lighter, and less stretchy. The lighter part begins to diminish when the required additions for cruising are added up: stackpack, full battens, taffeta on both sides, etc. My string sail main weighs 165 lbs in the bag, add another 60 lbs or so for battens when you hoist it. Too heavy to pick up without a crane, so what would another 20 lbs matter?

I have put a lot of effort into trying to keep these string sails from molding, unsuccessfully. I won't have them again till they figure out a solution. 

 

With the HN Radial I know the stretch resistance is more unidirectional, where as the HN crosscut is more likely to stretch in one direction.

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Just to be clear. The warp-oriented cloths are specifically designed for radial-constructed sails.

To me there's a clear benefit for shape holding to these over a cross-cut sail using standard fill-oriented Dacron. 

Perversely, because of the heat-set and other issues, if the Hydranet is more stretchy than a pure-Dacron cloth it's because of the spectra. As their advertising claims, however, it will be ultimately stronger, less prone to tearing, because of the spectra. North's claim is consistent with this:

Radian delivers lower stretch and higher performance than any other non-laminated polyester sailcloth. Sailors can now enjoy low-stretch radial performance without films and glues.

Not stronger, but lower stretch.

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2 minutes ago, kdh said:

Just to be clear. The warp-oriented cloths are specifically designed for radial-constructed sails.

To me there's a clear benefit for shape holding to these over a cross-cut sail using standard fill-oriented Dacron. 

Perversely, because of the heat-set and other issues, if the Hydranet is more stretchy than a pure-Dacron cloth it's because of the spectra. As their advertising claims, however, it will be ultimately stronger, less prone to tearing, because of the spectra. North's claim is consistent with this:

Radian delivers lower stretch and higher performance than any other non-laminated polyester sailcloth. Sailors can now enjoy low-stretch radial performance without films and glues.

Not stronger, but lower stretch.

I'm about 99.9% sure that Hydranet is NOT more stretchy than pure Dacron.

HN Radial and HN Crosscut are actually quite different cloths, they don't make the radial and crosscut sails with the same weaves.

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14 minutes ago, Rantifarian said:

Ddw, is 20lbs all it is between string and Dacron for your main?  That is much less than I would have expected. 

I don't actually know, as I have never had a dacron sail on it. Originally I was told the difference would be great, the problem is when you add the (many) weights in addition to the cloth, the weight differences in the cloth tends to get diluted. On the string sail I needed taffeta both sides, it isn't all that light and a pure weight addition for the string. The battens weigh the same, the stackpack weighs the same. I have asked 3 different sailmakers for an estimate of weight in Hydranet radial, none ever got back to me. There is an old thread back in the beginning of 2012 started by Estarzinger, it it he got estimates of a 700 sq ft sail where the difference was 22 lbs. (105 to 127). Trying to scale that to 960 sq ft and none of the numbers make sense: 105 should go to 144 but the sail I own weighs 165 without the battens. 

I'm not sure how much weight the mold and mildew add. 

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2 hours ago, B.J. Porter said:

I'm about 99.9% sure that Hydranet is NOT more stretchy than pure Dacron.

Which Hydranet and which Dacron? Again, warp oriented cloth is a different animal.

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10 hours ago, Veeger said:

DDW,  I've got a full batten, square top Hydranet radial main.  It's still too new to tell how it will last but looks good for now....

And I've had North's version: radial sails made with North Radian cloth. This will be my 6th season with them. Shape has been to me identical to the spectra Norlam that after 2 years mildewed to the point of my being embarrassed to raise them.

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Just finished a circumnavigation (well in January) with a radial Hydranet genoa. Still has very good shape, draft has not moved aft significantly. I like the stuff. This is a genoa on a 40' pretty light catamaran that regularly sails quickly in too much apparent wind :)

Here's part of the data from my sail's lot of cloth:  
Style : 383 HYDRA NET RADIAL
Lot-No.: : 31649
Act. Weight : 394  g/m² /  9,20 sm oz

warp 0° 1% stretch 133.5 lab / 130.8 flutter (lbs)

fill 90° 1% stretch 37.1 lab / 35.8 flutter (lbs)

bias 45°  lab 23,8 / flutter 22,9 (lbs)

Here's the generic numbers for Challenge High Aspect dacron 9.62 (9 oz), used on my very high aspect mainsail in a cross-cut manner. I'm not sure how much variation between these number and actual lots of cloth

warp 38  /   fill 150  /  bias 24.5

As you can see the Hydranet is nothing special compared to the lab numbers for Dacron. But it sure seems to hold its shape better than any Dacron sail I've used.

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Good reports. KDH, the woven and laminated sails were stored/furled the same way?

I've had infrequently used dacron sails end up with a little mildew on them, but you can just lightly beach them back to white. They say not to do that with laminated.

On a circumnav, or any full time cruiser, you are more likely to put the sails up somewhat regularly, and the sun can do a good job keeping them bleached and occasionally dried. I am a commuter cruiser, sails might sit furled on the boat for two months or more. No way they will stay dry anywhere we have been - Great Lakes, NE Canada, US East Coast, Bahamas, PNW - rain anytime or all the time. Off season I have them dried, bricked and stored. But once I get home to California (if I ever get home to California) they will probably be on the boat all winter too.

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8 hours ago, Zonker said:

Hydranet Radial, tri-radial construction

warp 133.5 / fill 37.1 / bias 23.8

Challenge High Aspect, cross-cut construction

warp 38  /   fill 150  /  bias 24.5

Let's use these numbers to make an important point.

The fill dimension is the width of the roll of cloth. Panels that are long enough to make a tri-radial sail are longer than the fill dimension so have to be made along the warp. Tri-radial construction puts the long dimension along the load path where the sail has to be not stretchy. This is why the Hydranet Radial ("warp-oriented cloth") sail has its strength (133.5) in the warp dimension--that's the load path for a tri-radial.

The Challenge cloth, from the numbers, is clearly a "fill-oriented" cloth--the strength (150) is along the fill. This is ok for a crosscut sail where the load path is sort-of along the fill, but much of the load is along the bias. When the resin in the sail flogs out or degrades the sail looks like shit.

The shape-holding of the Hydranet sail comes from the fact that it's a tri-radial made with an appropriate cloth--the load paths are lined up with the strength in the cloth.

A corollary from the above. The Challenge cloth along its fill dimension is stronger than the Hydranet along its warp. The spectra does nothing to reduce the Hydranet's stretchiness. A well made warp-oriented pure Dacron cloth would do just as well.

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7 hours ago, DDW said:

Good reports. KDH, the woven and laminated sails were stored/furled the same way?

I've had infrequently used dacron sails end up with a little mildew on them, but you can just lightly beach them back to white. They say not to do that with laminated.

On a circumnav, or any full time cruiser, you are more likely to put the sails up somewhat regularly, and the sun can do a good job keeping them bleached and occasionally dried. I am a commuter cruiser, sails might sit furled on the boat for two months or more. No way they will stay dry anywhere we have been - Great Lakes, NE Canada, US East Coast, Bahamas, PNW - rain anytime or all the time. Off season I have them dried, bricked and stored. But once I get home to California (if I ever get home to California) they will probably be on the boat all winter too.

I feel your pain.

Yes. Same use, seasonal weekends and week-long cruises. I roll up the sails when I'm done sailing, wet or not, even wet with salt water.

The difference is night and day. I think spectra in the laminate makes things even worse. Joli has the same issue.

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KDH, I'm not sure why:

--given UHMWPE's well known characteristics, one of which is lack of stretch;

--given that HN cloth uses UHMWPE fibre in the warp;

that the UHMWPE would do nothing to counter cloth stretch, especially as opposed to polyester (Dacron)?

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The UHMWPE is, even according to DP, a "ripstop." It's not under load. The likely reason from what I understand is that when the Dacron is heat set it shrinks but the UHMWPE doesn't. The polyester fibers end up tighter than the UHMWPE so they come into play only in ultimate strength after the shape has been sacrificed.

So the UHMWPE net, the ripstop, doesn't reduce stretch when the sail is new and well-shaped.

That's the theory, and the numbers seem to bear it out.

But importantly, like North Radian and WarpDrive, it's a warp-oriented cloth and is well suited to radial construction, which aligns the strength of the fabric along the load paths where it's needed.

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I'm beginning to doubt that modern sail materials, especially aramid and carbon that are susceptible to bending, are practical for a cruising sail where longevity is important. The construction method seems most relevant.

From a design perspective cross-cut cloth sails are horrible for shape from very basic considerations--where the loads are and how much does the cloth resist stretch in those directions.

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Makes sense. What occurs to me upon reading your explanation is that there would be some shape loss up to the point that the UHMWPE then takes up the load, then the loss would effectively stop, which is still less than a pure Dacron would offer, yes?

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4 minutes ago, Max Rockatansky said:

Makes sense. What occurs to me upon reading your explanation is that there would be some shape loss up to the point that the UHMWPE then takes up the load, then the loss would effectively stop, which is still less than a pure Dacron would offer, yes?

That's my understanding. But to further complicate the issue there is the problem of "creep" with UHMWPE.

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26 minutes ago, kdh said:

The UHMWPE is, even according to DP, a "ripstop." It's not under load. The likely reason from what I understand is that when the Dacron is heat set it shrinks but the UHMWPE doesn't. The polyester fibers end up tighter than the UHMWPE so they come into play only in ultimate strength after the shape has been sacrificed.

So the UHMWPE net, the ripstop, doesn't reduce stretch when the sail is new and well-shaped.

That's the theory, and the numbers seem to bear it out.

But importantly, like North Radian and WarpDrive, it's a warp-oriented cloth and is well suited to radial construction, which aligns the strength of the fabric along the load paths where it's needed.

As mentioned previously, the Hydranet Crosscut is a fairly different product than the Radial, even though it shares a name. It's more of a fill cloth since it is woven for corss cut construction. It has one direction it stretches, and one direction where there is basically none.

You make it sound like I'd get the same stretch on Dacron sails that I get on Hydranet Crosscut, but I'm not really buying that. Maybe it's the weight of the cloth we'd need for our size, but the HN Crosscut looks like a much better option

I had a lot of discussions with a friend that works for DP before we ordered the new sail. He shared some of the test numbers with me (I'll ask him if I can share his e-mail, I told him about this thread but he may not want to be drawn in) between HN Radial and a radial, polyester-only cloth. There was a significant difference in the warp-pull tests in favor of the Hydranet.

The fill direction pull tests on the Hydranet Crosscut were similar to their premium bluewater cloth, which puts the HN Crosscut at a big disadvantage because it's way more expensive. The HN Crosscut would have cost a few hundred bucks less than a polyester radial sail. The HN Radial sail cost about 20% more than the radial in polyester cloth.

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BJ, that of course would be the relevant test. A pull test in the warp direction between HN Radial and another polyester-only cloth like North Radian or WarpDrive.

Which warp-oriented polyester-only cloth did you consider? North has a patent on the Radian cloth process--unlike with a fill-oriented cloth the process matters.

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8 hours ago, kdh said:

That's my understanding. But to further complicate the issue there is the problem of "creep" with UHMWPE.

Well... to stop creep in UHMWPE line, it's heat treated, albeit IIRC under load. And you have informed me that HN is heat set, so...

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What we need someone to do, is test these materials to destruction to see what the curves really look like. The 1% stretch figure is only one point on that curve. Dacron and PE have very different stiffnesses, and from the heat set maybe very different "preloads" so certainly you could speculate that at 1% the dacron carries nearly all the load and yet at 2% the PE carries nearly all the load. The fabric companies probably know the answer to this, but may have reasons for not publishing the knowledge. 

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I'm surprised at how little information there is. It seems the marketing approach is to appeal to mystique.

The history is littered with attempts at pitching new materials as the way forward. 

I think it's interesting that both with North Radian and now with 3Di NORDAC North are willing to backtrack and be plain with the idea that polyester with thoughtful construction methods is the way to go for the cruising sailor. I respect the courage to convey and offer products based on what they've learned even though it's in conflict with their own history.

https://www.clubracer.eu/2017/4/7/north-sails-launches-3di-nordac

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If someone called Tom Davis at North Mildford, and sweet talked him :), you could get the information. 

I dont know what he is doing these days, but he was head of north cloth, and had good test equipment. He had a ton of comparative data, and if did not have exactly what you were looking for, could easily get it.

He's a good guy.  Most of North management only knew and cared about the grand prix crowd. Tom was one of the few who knew and cared much about 'the rest of us'.   

I actually have quite a bit of radial hydranet test data , but it is old(ish) might not be current, and dont have an apples to apples comparison to a radial dacron.

 

kdh - you are obviously a 'glass mostly full' type of guy - that is sweet :) I personally have less 'flattering' ideas both about why North does not publish much test data, and why they are pursuing dacron 3di. But which of us is right does not really matter.

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