More Mainsail chat!

[GregPitt]

I am new to national 12 sailing and as a sailmaker I am currently spending a lot of time looking at photos, class rules, mast bends etc.... Before I started looking too closley I couldn't help noticing an ugly looking crease in every National 12 mainsail when sailing upwind in a bit of breaze. I'm not starting to realise why.
 
Basicly the width measurments permitted in the class rules are too large for the maximun lenght of battens permitted, meaning the battens are not long enough to support the roach of the sail. I know the width measurments were increased in recent years, would it have been in the interests of nice sail shapes to allow longer battens aswell??
 
This leads onto previous conversations about full length battens.... 
 
Would they be better for heavier weight crews?... No better than they would be for a lighter weight crew, but would give you a smoother sail than present class rules allow.
If your a lighter weight crew and you had the option of full lenght battens would you take them?... Yes of course you would. I can't think of a reason why not. Smooth sail, it would still allow you to depower, it would be as versatile as a standard sail both up and down wind. Thought I think the thing that would please the most people is that it would hold a good shape for a lot longer. Laminate cloths loose the mojority of their strength through floging.
 
Is this something the Class should seriously be considering and possibly something that should be bought up at an AGM?
 
Greg N3473  

[flogging (Guest)]

Greg
 
Interesting points.  I assume that the creases you’re talking about are those running from the clew up past the inboard end of the bottom batten?  First a factual correction;
 
The half and three quarter widths were recently increased as you stated.
The quarter width was actually reduced by a significant chunk.
The overall sail area was kept approximately the same, i.e. the increases were made because the reduction was required.
The reason for these changes was for exactly the reason you highlight, to remove this crease caused by the batten trying to support excessive roach.  This was the solution chose at the time, rather than changing the batten rule.
 
You often also see the creases going all the way to the spreaders, usually when we over bend the rig when the breeze gets up.
 
The full batten and fat head debates come up from time to time, I believe they are separate, but related debates.  I guess they were last considered in detail about 3 years ago.
 
I’m sure they will be discussed again in the future, as is only right.
 
As I recall some of the cons of the full battens at the time were;
Tacking battens in light winds, particularly inland.
New stiffer masts required (cost).
More expensive sails, balanced by less replacement required.
Powering up the lightweights earlier, increasing the fat/thin divide.
 
New views are always interesting, what have you got?

[andymck]

Just to counter the perceived problem with tacking fully battened sails in light winds, the only sails I have ever had a major problem with are those carrying a single top batten. Having sailed fully battened mains from on boats from 200's to 18 foot skiffs, one of the things that does put me off coming back to 12 sailing is the dreaded top batten. I am not the only person that thinks that fully battened sails are easier, a recent discussion with a respected international umpire suggested that the only class they tend to have an issue about batten popping in light winds at olympic regattas is the 470. I recently have been sailing a boat with a double top batten, and 2 partial lower battens, this produces a very stable sail, that is easy to tack, and easy to depower, and also gives a modern shape, and should be a consideration next time the discussion comes up.
On an aside are there any foolish or numinous owners looking to upgrade soon? The lack of good second hand boats is making the Merlin 2nd hand market look easy.

Andy