The problem with less downhaul is that when the leech becomes tight, the entry around the boom, where the power comes from, becomes loose. I would prefer a bigger sail properly set.

Francone said..
Since I sail mostly in light winds, my overriding concern is not to waste ANY wind power. From this perspective I wonder whether one should not make an exception to the “ golden” rule of a strong downhaul, which is normally strongly recommended.. In fact, when sub-planing in light winds, (12 knts or so) having the top of the sail loose down to the 2nd panel through a strong downhaul, as normally recommended, combined with a loose leech, unnecessarily depowers the sail, I think. This may explain why I always have to use very large sails ( 8.5 +) in order to get going in light winds. However I am caught in a sort of catch 22 situation, because when I try to keep the downhaul to a minimum in order to have a tight leech, then the sail becomes very hard to rotate. Perhaps this is the lesser of the two evils, after all, because I can always push out the sail with one hand. Even if it didn’t fully rotate, I wonder whether this is more serious than spilling too much wind. I wonder whether any body has comments on this

Thanks

Francone

If your sailing in 12 knts you got to use something bigger than an 8.5, you could always buy a race board sail something like this http://www.loftsails.com/products/sails/raceboardblade

Longboard and RS:X racers usually sail with adjustable downhauls and outhauls. I've seen an RS:X rigged by an olympic sailor, and she could switch from a totally tight leech to a fully loose leech (down to the boom) in a couple of seconds. But she'll use the same 8.5 sail to plane in 8 knots and it 30 knots, and weight about half as much as I do.

The Kona One sails also have a huge trim range - probably several cm to inches downhaul, and at least 15 cm outhaul on the larger sizes. They don't rotate easily anymore in light wind settings, you may have to use your hands or knees to push.

But how tight a leech you can use depends a lot on the sail. Most sails are made for much more limited wind ranges, and often behave very badly with just a cm or two too little downhaul. For example, they may feel very heavy, and become unstable even in small gusts. Another common problem is that the battens poke out too much, which can quickly damage the batten pockets. Sails designed for very wide wind ranges, like the RS:X and Kona One sails and longboard sails, usually don't have these problems.

Yes, as above. Don't over think it. Go with manufacturers recommendations. They have done the work for you. If you are used to sailing boats you have to leave your old tuning skills behind. A tiny bit less downhaul is ok in the light stuff (10-20 millimetres), but if you attempt to bag it out hugely with downhaul adjustments you're just going to get a very sore body for no increase in speed or efficiency. It will be like wrestling a circus tent.

Don't forget that the outhaul has a big part to play also.
Try rigging with say 3/4 recommended downhaul and neutral outhaul for light wind.
As the wind picks up it is easy to adjust the outhaul and the sail will be sweet.

+1

I always downhaul my sails to the max (even in light wind) and just play with the outhaul.

those point 7 need to be tamed or you'll only be sailing 1/2 hour before your arms are gone....

If you don't like using big sails--- a smaller size sail with a tight leech will provide nearly the same power.

If you sail very deep off the wind though,the larger sail will provide much more power.

I can get my bagged out 7m Pryde slalom on a 122 Patrik with a 46 fin going nearly as early as the anyone with the 8.6m.size.

The 8.6 to 8.7 seems to be the 'in' size at the moment for light 10-15 knot conditions.

Were I to use that size--- I certainly would use more downhaul and outhaul.

Much prefer the lighter feel of a smaller sized sail.

As the boom and luff length increase------ the swing weight increases too.

The rig maybe light as----- but the swing weight makes it feel heavy.

recommended down-haul bro.

If you really want to test rigging go windskating you can just drop sail& change rigging & check preformance all the time & you can then easily determine if its going to work on that particular sail then you can note optimum performance . . Bet it will be factory specs . But it is a good way to experiment.

Joe I like your style