Main Sail Battens - Full or Partial

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Edwynn

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Oct 11, 2009
5
MacGregor 26x Douglaston, NY
Hi all,

I just posted this on the all boats forum and then realized that Mac owners would be more able to help me. Basically, I'm getting a new mainsail for my 26x and I was wondering whether full batten sail will increase performance.
 
Jun 5, 2004
997
Macgregor 26D Boise
The batten question is not unique to Macgregors by any means. Most sail offerings are 4 regular battens on the mainsail leech, a powerhead mainsail which consists of two full battens at the head of the sail, and two regular battens, and 4 full length battens. Battens allow for mainsail shapes that would otherwise not be possible. Full length battens also prevent sail flogging. Full length battens are more expensive, and unless you remove the battens, the mainsail will always be a long tube when stowed. Full length battens work well with Stack-Pack or Dutchman stowage systems. If I had it to do again, I'd get the full length batten mainsail.
 
Jul 7, 2004
8,469
Hunter 30T Cheney, KS
They also add more weight aloft and make the Mac more tender than it already is.
 
O

oreana1234

Justin, I just want to add, that if the sail develops more drive as a result of having the sail in a better shape due to having battens, the net result will be forward motion, and not increased heel. Just my thought
 
Jul 7, 2004
8,469
Hunter 30T Cheney, KS
I'm no expert by any stretch but I have some engineering experience. It seems like the goal of any sailor is to keep the weight as low as possible CG-wise. The more weight you add higher up, the harder it is for the boat, especially the Mac, to counteract it. I would think that goes for more power too which does cause the boat to heel more as the force on the sail increases with nothing more to counteract it. Forward motion may reduce leeway but I don't thing it factors in to heel.
I'm not saying full batten sails are bad, you just need to now what you are getting in to.

 
O

oreana1234

And again if the sail develops lift instead of just being heavier, the vector of force for the lift is forward, in the direction you want to travel. Think about blown out, bagged out sails with or without battens, and why they cause heeling. While no extra weight is added throughout the life of the sails, (if anything the sails weigh less), the lack of airfoil shape after stretching causes heeling instead of lift. The question is: does the addition of the weight of the battens, offset the advantage of the ensured airfoil shape that the full length battens give you?

And by the way, I have gone full circle with additions to my rigging. I used to have an antenna and masthead light aloft, along with the necessary cable and wiring. No more, I don't want anymore weight aloft than necessary. I do have two full length battens on my new(ish) mainsail, and the draft stripe tells me that it is shaped nicely. If I were to purchase a new main, I'd get it cut to take advantage of the shaping that 4 full length battens allow, I'd even set it up to have a square head.
 
Jul 7, 2004
8,469
Hunter 30T Cheney, KS
The property of "lift" is just that, an upward force on the longer (leeward) side of the foil (sail). What produces the forward motion is lift of the sail counteracted by the keel and ballast. If you can't counteract the lift you are just going to go further over. A more powerful sail on a windy day is going to require a larger counterbalance to maintain forward motion. Anything that pulls the sail over, lift or weight, is going to require a counterbalance. If you can't compensate with a low CG you have to either reduce weight (trivial in the scheme of things) or de-power the sail. Obviously that is why you will see the crew hanging over the windward side when they are sheeted in and going for it.
 
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Jun 5, 2004
997
Macgregor 26D Boise
I am no longer sure what we are discussing. I still see battens used in sails, their weight being offset by their effectivity. I know that sail shape is also an important factor in lift production and resultant forces that make the boat go...
 
Jul 7, 2004
8,469
Hunter 30T Cheney, KS
Simply that a heavier, more powerful sail is going to heel an already tender Mac over quicker and that you need to consider that when you decide on a new sail. A traveler will help but on windy days you are going to have to compensate for the extra force somehow.
Personally, and again I'm no expert, I think you can get good sail shape with a well designed, lighter sail without full battens. An extreme example would be Kevlar.The only reason I would get full battens is to assist in lowering the sail - with lazyjacks. To each his own.
 
Apr 30, 2006
610
Macgregor 26s Kemah, TX
At the risk of keeping open a thread that should have died a natural death about ten entries ago, I thought I'd shove my oar in.
For the last ten years that I owned my previous boat, its main was full battened. That main lasted longer than any of the others and was still in very good shape when the boat was lost in Katrina. I attribute the sail's long life entirely to the full battens. In addition, the battens did help help the draft or foil shape. If I had one criticism, I would say that it was a little harder to tweak the shape when racing, or to flatten it when it was blowing hard. But it could be done.
OK, here's where I enter the controversy. The battens are pretty thin, light fiberglass and the two up top are much shorter than the lower two. I doubt the weight up top is that significant. On the other hand, my old boat was pretty heavy and the Macs are light so weight up top is a consideration.
Personally, if I ever have to replace my main, the new one will be full battened.
 

Edwynn

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Oct 11, 2009
5
MacGregor 26x Douglaston, NY
Thanks for the input. I'm still not sure what direction I'll take, but I'm leaning towards full battens. I'd like to sail faster in light air and it seems the better shape will accomodate that. In heavier air, I reef very early, finding that I sail faster with the reef instead of being overpowered.

Thanks again
 
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