He can't proof anything with a photo.

The reason for it is very simple.

Design a shaped sail using basic 2D cloth by a method called broad seaming. But instead of having a single layer of cloth with stitched overlaps on the edges (= seams), make it out of multiple layers, 2 or 3. When designing these shaped panels make sure that the panels that belong to a given layer have "egdes" (if we may not call them seams) that are shifted relative to the edges in the layers above and below it.

Get a 3D workbench (like a model airplane wing) and lay the first layer of panels with their egdes butt to butt and lay the second layer of panels, the ones with their egdes in different locations, on top of the first and also butt to butt. Glue the pack together. Repeat this for every new layer.

Basically, the small (stitched or glued) overlaps that most of us would easily recognize as "seams" are now transformed in very broad overlaps that most people won't recognize as easily as "seams". The lack of stitching because glue was used reinforces this impression. The irony of course is that the name "BROAD seaming" is probably more decribtive of this new layup then it was for the old way of joning panels. But that is a side track. Of course to improve load bearing properties a maze of fibres is glued between some layers, introducing all kinds of small lines running in every direction hiding the splits between the monofilm panels; but that is not important in the shaping part of the analysis.

Of course forcing these curved egdes of the panels to REMAIN back to back is what is shaping the sail when it is removed from the mould (3D workbench). These transitions from one panel to the next inside a single layer are the "seams" of the 3DL sail. They force shape into the sail in exactly the same way as "broad seaming" and therefor it is "broad seaming".

Everybody can try this himself at home using pieces of paper or plastic bags and glue or BROAD duct tape. I made shaped stunt and power kites that way as far as 25 years ago.

Of course promotors and other persons who are not too smart will now claim to have pioneered a totally new shaping proces that is completely different to broad seaming. Their proof ? Just asking anybody to point out the "seams" in a photograph.



Guys, this is all pretty old news. Even sailing magazine articles as old as 2004 have described it in similar terms :

http://www.sailingworld.com/sailing-gear/sails/changes-in-racing-sails-and-sailmaking-33336.html

and I quote :





Model airplane builders have been using such techniques for decades before North Sails gave it a fancy name.

Why is everybody falling every single time for the debating techniques of Macca where he is arguing the impossible ?

Wouter

Then Wouter somebody had better call the Finn class and tell them that 3DL sails are ok to use without cutting and inserting seams as they currently do.

The rule in the Finn class (which is heavily scrutinised by sailmakers, sailors, federations and ISAF) clearly bans sails that have Continuous layers or fibres crossing the seams. If there were seams in a 3DL sail then they would in fact be legal for class use.

When you are finished theorising you can get back to reality and pull your head in.

Wouter, please refer to your post #133215 in the F16 weight thread.

You say the following:

"I think I'll go with North Sails on this one. Time to admit you have been busted redhanded Macca, again !"

Thanks James, I was to pissed off to go back and find that post.

"To go with someone" means something else then "to go to someone".

Especially in the context of the complete wording used in post #133215 where a direct reference is made to a statement made by North Sails themselves.

And "threatening to do something" suggests a whole different choice of words altogether.

Do I need to explain that to you as a non-native English speaker ?

It is just me or is the level or intellect dropping sharply lately ?

Wouter

Wouter, I just had a thought:-

You could sell your theory on 3DL sails to the highest bidding Olympic federation. They are all looking for a edge in the upcoming Beijing Games. The Finn sailor that has a full 3DL sail will have a nice advantage over his competitiors.

All you have to do is convince the ISAF measurer that the Continuous layers or fibres are indeed crossing the invisible seams... Good luck with that <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />

So you are saying that you are going to agree with North Sails on the issue?

Macca, when you go to the North factory can you take a look at the 3Dr fabrication?
I just watched the 3Dr Tour on their website and the way they construct those sails is nothing short of amazing.

A must see for anyone who enjoys technology and sailing:
http://na.northsails.com/3Dr

Maybe a better question for us all is why any class would want to ban 3D sails at all ?

Apart from the obvious semantics, there is bugger all in it !

And if that drum production proces of North Sails proofs to be able to produce good 3D sails in a cheap manner then why not make use of it ?

Wouter

I was thinking, why would any class ban a sailmaker, then it came to me. If indeed the 3DL sails are "up to 20% lighter" and they have a patent on the process, that pretty much means no other sailmaker can build a similar light sail, so in effect, the whole class would have to buy from North if they want the lightest sails.

Is that why they did it?

Also, I thought I read a few years back, that someone was suing North over patenet issues involving the 3DL process, and North lost, and had to buy them out of the patent, is that the case? I thought was Sobstad or Ulman, or someone else, who actually invented it and North stole it. Perhaps the patent should expire so all the sailmakers can use that method.

Also...(bored today) why has nobody come up with a spray on fluid which would dry to shape, to replace the mylar film? Seems you could just spray the mylar type stuff in place and forget about seams alltogether. Calling Dupont and 3M... <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

The play for the patent is in my opinion one reason why it may not be called "broad seaming". Because if it is identified as such then no patent could have been awarded and everybody could have made 3D sails. But that is a different topic.

More important is that 20% of next to nothing is still next to nothing.

A normal F16 radial mainsail, excluding battens, weights something like 3.5 to 4 kg. 20% of that is onlu 0.7 to 0.8 kg (= also less then 2 pounds). If that amount of weight savings puts you below minimum weight then you have to put it back on your boat again as lead.

20% weight savings may add up to many kilograms on large yachts, that do carry many sets of sails, but on a F16 where only a single suit of sails is allowed, it is almost negligiable.

Patent problems : It was indeed Sobstad and yes the patents are soon ending. So if anything we can expect alot of competition in this field driving down prices. That is, when assuming 3D sails are attractive enough commercially for sailmakers. I guess we'll know soon enough.

The "spray" idea is basically 3D polymerization and we have already covered that earlier.


By the way, Marcus used a "tapedrive" (tm) mainsail on his Blade F16 at the GC 2007 event, this is extremely similar to 3D sails. The difference is mostly that it is made by somebody else then North Sails. I showed his mainsail to some potential customers who came over to check out the F16 boats as Marcus wasn't available himself at the time. The sail felt light but also a thinner then some of the radial sails I handled.

For of large picture of this sail follow this link :

http://f16.beasts.org/gallery2/main.php?g2_view=core.ShowItem&g2_itemId=6095

And click on full size version

Wouter

Hi Tony,

I will try to have a look when I am there. Its not allowed to take pics inside the 3DL section but from what I have been told the 3DR area is not so secretive. I have not seen it in person yet as it's been a few years since I was last in the US.

3DR has potential to produce moulded (seamless) sails for almost the same cost as a traditional panel sail. That is a good thing, however as the Tornado class has proven its not a good situation to allow a technology that is only available through one supplier

Actually its very much the topic: If the matter has been to court and each party was clearly trying to win their case (spending a LOT of money to do so) and it as found in that court of law that there is a difference in the way a 3DL sail is made, hence granting patent status. That should be proof enough for Wouter? Or was the Judge mislead??



Rather have it as lead on the boat, than weight aloft. Furthermore, as a percentage of total boat weight 0.8kg in a 107kg boat is a lot more than 5kg in a 5500kg boat.


having sails below deck on a yacht is not really an issue with regards to the weight carried. In race yachts we try to add weight in the right areas and if the max design displacement is a class/formula rule then we sometimes add water to the bilge in order to increase the sailing displacement. Sounds a bit crazy but the science is sound.

Wouter, you must have missed my post above where I asked if you would accept North Sails version of Broadseaming in relation to 3DL?

I chatted with Fletch about sail manufacture at Christmas time. Most of the European Tornado teams are using MAX cloth in their sails, thus allowing cleaner lighter sails. When I asked Fletch about it, the gist of the conversation was that in general they were better sails than radial cut sails, in fact when a couple of Aussie teams were looking to buy second hand sails of the Euros I believe he suggested they make sure they were MAX. However, for their program (Bundy and Gashby) after doing their due diligance they decided to stick with radial sails because with Fletch and Gashby both looking at the sails in the lead up to a regatta the radial sails give them the ability to make minor tweeks to the sail each day until it is perfect. With a max sail this would be significantly harder. 3DL and 3DR sails are illegal on Ts anyway but based upon this discussion, I don't think the world's best Tornado sailors would use them even it they could.

The worlds best Tornado sailors would for sure use 3DL if it was allowed.

In fact in 1995 Chris Nicholson had a 3DL sail made for his Tornado. The benefits are clear that a 3DL sail will be lighter and have a completly repeatable shape which negates the need to make those little tweaks.

Maxx cloth is made by Contender, it was the first cloth used in the latest crosscut development, now however the top teams are using Flex which is made by Dimension. The Maxx cloth was not stable enough unless you used the carbon version which is banned in the Tornado. The New Flex sails are showing promise.

Its is a lot easier to make a change to a Maxx or Flex sail than a radial sail. The Seams are located at the batten pockets and all you have to do is split the seam at the pocket, make the change and stick it back together. A radial sail is a complete nightmare to alter seam shape on the radial panels once the sail has been made.

Its is a lot easier to make a change to a Maxx or Flex sail than a radial sail. The Seams are located at the batten pockets and all you have to do is split the seam at the pocket, make the change and stick it back together. [/quote]

Sorry macca,

Here's a little insight on how difficult it is to change the panel shaping of the cross-cut Flex or Maxx cloth sails.

Since they are GLUED then stitched, the panels are "locked" resulting in a sail that cannot be unstitched to tuck/tighten the leech. The radial in this effect is easier to tune because you are tightening the horizontal joining seams, not the radials. The 3M glue sailmakers are currently using does not allow for the seam to come apart.

For everyone's education,

Bob <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />

Bob, you had better send a tube of that glue to the Tin Can Tri guy! <img src="http://www.catsailor.com/forums/images/graemlins/blush.gif" alt="" /> Better yet, two tubes! <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Bob,

Maxx of Flex sails can be joined in a number of ways. for a production (ie a sail requiring no more development) sail they can be glued as you describe (which is actually ultrasonicly activated) and do not need stitching, or if you are developing sail shapes and want to alter the seams you simply use venture tape and sew the seams. then its super easy to alter.


for a little more education <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />

Wouter,

When you get a chance can you give us an answer to this question:-

Are you going to agree with North Sails on the broadseam in 3DL sails issue?

So, when I was personally involved with Contender almost a decade ago when we first started down the cross-cut laminate road, we quickly realized the seams were pulling apart when using venture tapes. That's why way back then we went to 3M and had them get involved with a better glue for the seams. In order to fully achieve even a test sail, you must glue. You can't evaluate cloth when other things are moving too. We learned this almost a decade ago.

The Flex and Maxx cloths are now getting better (more fill yarns) and I think after the Olympics it will be a cloth to look into. Until then and we get longevity and stretching reports, radials are the way to go in multihull sails. Really, this is all old news on how to build a cross-cut laminate sail.

We all know it's much more cost effective to build a cross-cut sail, the construction process is sound, and the problem still remains the long-term stability of the cloth.

Furthering education,
Bob <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />