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View Full Version : The Importance of Being Outhauled


k.lauman
6th December 2008, 11:24 PM
Been using a 7.5 Naish Freeride sail since spring, and having some problems. I wondered why it felt sluggish, heavy and inefficient. I was ready to give up and go back to a 6.5 V8 from the mid 90's which semed to power a Carve 111 just as just as well as the Naish.

Some observations and questions: using only downhaul and lots of it to clean up the leading edge and minimal outhaul equaled a sail that was baggy down below, flat up top and a very twisty leech. Lower CE?

Using only enough downhaul to allow the most overlapped-against-the mast batten to just about rotate freely , then adding a forceful amount of outhaul ( need to sit and use legs) equals a firm leech, and an balanced distribution of camber with forward draft all the way up and down the luff area.

Question is, which is more powerful in light/moderate planing-strength winds? Bagged out bottom and loose leech or a firm leech and a shallower forward draft that runs up and down the luff of the sail?

steveC
7th December 2008, 01:46 AM
Not with the team, but I thought I would offer an opinion. While I'm not using Naish or NP sails (I use Windwings and Hansens), I find that I really don't like the minimum outhaul scenario, as it yields a heavy feeling in the sail that is less balanced overall. What I found works best for me is lots of downhaul and a fair amount of outhaul too. It keeps the power down low with good exhaust off the top, and offers a shallower draft overall. This results in a lighter handling sail that still has plenty of power too.

There is one caveat though, I'm a fairly lightweight sailor at around 75kgs. Also, my two larger sails are 7.1 and 8.3, and I rig them camless for rigging and jibing ease. However, using cambered sails in the past, I still applied the same rigging strategy.

Chris Pressler
14th December 2008, 09:08 PM
A certain downhaul is necessary, but too much can kill the performance totally. You can downhaul, get the boom on, press the sail with one leg down to the ground at th ebase. A second person should press the mast top down in the direction of the ground. Now the whole rigg gets a tensionto the lee side. Have a look if there are many crinkles, especially in between the foot and the second, third batton.
Concerning the outhaul: especially for bigger sized sail. Donīt flatten them out. A vario trimsystem is fine, so you can adjust while sailing and adopt the specific profile fitting to the angle towards the wind.
Higher or lower thimble. I prfer th ehigher one, which seems to give more power and the boom get s more in a parallel position towards the boarddeck.
Hope it helps, but the specific sailtrimm is really different with different products.
Chris

k.lauman
15th December 2008, 10:56 AM
Thanks Chris Pressler, this thread is in the big leagues now! Yes, i've made the mistake off too much outhaul, a flat board makes a bad airfoil indeed.
And true, every sail brand and discipline is different. The naish 7.5 looks quite a bit different than, say 5.0 and 4.5 wave/crossover sails besides the obvious size differences. The Naish seems to maintain foil depth with extra outhaul tension and minimal downhaul with the draft moving forward. The 5.0 hot sails looses all it's low end power with the same configuration. Different sizes different tension, different draft and different tension settings.

Chris Pressler
15th December 2008, 08:11 PM
Hi,
would suggest to stay with a downhaul you like it right now, never downhaul too much, and play with outhaul. release it and feel, how the handling will be and the acceleration, the balance and the endspeed. Play around with the mastfoot position (move it out of the sweetspot by 2 cm back adn another time by 2 cm forward). Adopt your boomheight and so on (strapposition, finsize in terms of length, rake and area, harnesslines, harness...)
There are many opportunities to change something.
Take a little notice of your new ideas after your sessions on the water and will find out, whatīs the best. Use the sail also in not ideal conditions (too light or too strong).

All the best,
Chris