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It would be awfully nice to hear something from RS about the change that occurred in the thickness and stiffness of the top two sail battens. It impacts the one-design nature of the class and deserves to be addressed. Even if the reply is, "North Sails made the change and we didn't notice", or whatever. Any response would be much appreciated.
I too am interested only in the thickness of the battens.
I have measured the top battens in my 7 sail and the length is as quoted elsewhere on this site. They are also reduced enough at the ends so they adjust correctly.
However they are 3 mm thick. I would be very interested to learn if other sails have 4 mm thick battens.
The issue that I raised is a change in the thickness of the battens, not the length. Either way the batten has to be whittled in order to fit into the adjuster (and even more so for the new thickness). In both cases it's been done sufficiently to allow the batten to fully insert to the set screw adjuster.
So let me try again. Does anyone know when the batten thickness was increased, and why? I'm not complaining about the change, which is positive, but I think it's an event that should be known to the community of Aero sailors.
There is a very good explanation, what you can do at the page from Joern Domres:
It is in German language, but I think the photos are also quite clear.
Main issue is not the total length of the battens, but the end, which is maybe to thick to fit into the fixture at the and of the battens,
Maybe this helps.
May I suggest both of you have a look on the Forum under 'Class Rules Enquiries'.
There are two entries under the heading 'Batten Length'; one with seven posts and > 1000 readings. There you will find a lot of information about batten lengths, changes to the top two battens, and also the importance of correct fitting; particularly the depth of the shoulder for the adjuster.
If the shoulder depth is insufficient, it should be => 450 mm.
Then the top part of the sail will have too much depth and no amount of screw adjustment will reduce it. It will also be difficult to pop the battens on a turn. And difficult to sail close to the wind.
I'm very interested to know if anyone else has had a similar experience. I have an Aero 7 which is 145 boats earlier than this and I struggled to get the top of the sail to look right. I'll measure my battens as soon as I can.
I recently bought a seldom-used Aero (#1983) with a 7 rig. I began to notice that the upper portion of the sail was unusually curved compared with others, even while sitting next to them on the beach waiting to launch. No amount of adjustment of the sail controls or the batten screws would make it look anything like the others. Also, compared with other 7 rigs I had sailed, it was far more difficult to pop the battens after a tack or gybe, regardless of the adjustment of the set screws at the ends of the two top battens.
I then compared the top battens to those of a new sail, and found that they were substantially thinner, 3mm vs 4mm. That is a 33% increase, which gave them substantially increased stiffness. When I switched out the thin ones for thick ones, lo and behold the curvature decreased, and the sail popped across much more easily.
The Aero has had a number of tweaks to its design since it was first launched. All were publicly known, and none (in my opinion) had a big effect on performance. While the batten change is a positive one, it's hard to make the argument that it's not affecting the performance of older vs newer sails (independent of wear and tear issues). Maybe I've missed it (certainly possible), but I don't recall any publicity on this switch, nor do I know when it occurred. Another owner's older sail also has the thinner top battens, so my case is not a fluke.
Can anyone enlighten me on the history of this change?