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Old 10th August 2008, 08:02 AM   #8
Roger
Dream Team - School Guru
 
Join Date: Aug 2006
Posts: 2,110
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Hi Franco,
He means the "lee" rail which is the one across from where you would normally stand.
So...... you need to get your feet so that your heels are maybe on the centerline.
Or... you can place your back foot against the centerboard knob and sometimes "tip" the board lee rail down (the lee rail is the side opposite where the wind is coming from.
At your skill level, you may have never found out that tipping "Bertha" to the lee side would make her "come alive" and go upwind on lift from the centerboard.
That's really what you are trying to do here. Tip the centerboard so it is inclined to the point that the tip of the CB is well upwind of the "root" of the CB.
This gives you alot more upwind "lift" and also gives you a little bit of "upward" lift so the board goes much faster and higher upwind.
Tony is correct, for the wind range you suggest.... for very light winds (i.e. < 8 knots steady) you need a larger rig! An 8.5 m2 would be good. Give one a try.
Something you stated in your earlier reply has caught my attention........?
Why would you ever want your sail to be nearly flat?
ALL salls (from miniscule < 4.0 m2 high wind sails all the way to 12.5 m2 Formula sails) depend on the "draft" (your term was " a bit hollow") to give them power, and the larger the sail, the more draft/shape it's likely to have.
If you have been pulling on the outhaul alot, you have been making your "NeilPryde RAF Warp Oriented Slalom 6.4 sail, with 4 battens" as "non"-powerful as is possible.
Try this next time:
Downhaul your sail until the crease at the front of the luff sleeve is about 45 deg. pulled around the mast ( for the max. distance from top to bottm possible).
Then just add a touch of outhaul.
If your boom has the normal couple of pulleys in the back end, run the outhaul line from the boom end through clew grommet on the sail, then back through the pulley, then back through the clew grommet, then back to the cleat on the boom end.
Grab the outhaul line between your thumb and first finger (adjacent to your thumb) and pull straight back from the end of the boom. When the line slips between your thumb and finger, you are at "neutral" outhaul.
From there you can pull about one additional inch to give your sail a little "positive" outhaul. You do not need more than this for winds < 20 knots on a 6.4 m2 rig.
Sounds like you are not downhauling nearly enough to bend the mast so it has a curve that matches your sail.
Also sounds like you are pulling "bend" (or at least trying to anyway) into the mast with the outhaul.
This is not how modern sails work.
All the "mast bending" and shaping of the luff sleeve is done with the downhaul.
Here's a simple way to figure this out.....
Lay your sail (without the mast inserted) out on smooth wet sand, or perhaps on your driveway.
Take a stick (if you are on smooth wet sand) or a piece of chalk (if using smooth concrete or asphalt) and draw the curve that's sewn into the luff sleeve (in other word, draw the curve of the front of the luff sleeve as it lays flat.
Then move your sail away from the curve you have drawn, and put the mast in.
Then downhaul your sail. Keep moving back to the curve you drew and adding more downhaul until the mast is bent to that same curvature.
This should bring the crease at the front of the luff sleeve around to about 45 deg. from the front or side (45 deg. being halfway between 0 deg. and 90 deg.) for most of the length of the luff sleeve (except perhaps right at the top and bottom where the mast comes out of the luff sleeve and engages the tack fittings and the head fittings.
This will demonstrate to you how much you need to bend the mast.
Then, with the correct downhaul to bend the mast, you can think about putting on the boom and adding a little outhaul to lock the draft/shape into the sail.
Maybe part of the problem you are having is that you are "stretching" all the draft out of the sail. If you do this, you may as well use a piece of plywood, which won't get your board moving any better than a stretched out sail.
Hope this helps,

Last edited by Roger; 10th August 2008 at 08:06 AM.
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