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  #91  
Old 09-12-2011, 03:01 PM
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brian eiland brian eiland is offline
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Movable tacks of all sailis on this rig, and how that might effect pointing abilities:

WishBone Sailing Rig
posting #182 and #183
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  #92  
Old 09-22-2011, 10:22 AM
Paul Scott Paul Scott is offline
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Quote:
Originally Posted by farjoe View Post
I have often wondered why a mail sail with that shape is faster than a reefed mail which can then be properly set. I just don't understand it.

Yet most racers seem to prefer racing with a distorted sail so it must be faster.
Paul Elvstrom showed, a long time ago, in the Dragon Class, which by class rules has two jibs (basically blade and overlapping), that leaving the overlapping sail up in the big stuff and luffing the main won races. I don't think that has changed, has it? In the Dragon class, at least.

Paul
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  #93  
Old 09-22-2011, 10:51 AM
Paul Scott Paul Scott is offline
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Originally Posted by Mikko Brummer View Post
Yet another one: Two mainsails, same area. The ORC VPP thinks the Fathead is 0,02 kn faster in TWS 6 kn (5,09 kn vs 5,11 kn), and 0,02 kn slower in TWS 20 kn. The break even point is 12 kn, pretty much when the boat reaches its "design wind" and stability becomes an issue.

I understand that, but I actually have an experiential tale- when we bought our U20, I bought the class legal full sail ( fat head ) with a reef point, and the class legal high wind sail ( pin head). 9/10 th rig. Both sails by Glazer. The reef point brought about the same luff length as the high wind sail.

The pin head was incredibly hard to handle in a breeze, in comparison to the fathead. The pinhead felt just like, well, a pin head. Jerky, foul mouthed. It was the ability to twist the fat head smoothly off the wind, both actively and passively that left the pin head in the garage. I was going to have a high wind fat head or even a squarehead made, but never got around to it.

Against other U20's in bigger winds, it was because of the staggering nature of the pinhead that you could see the fatheads move forward with each jerk of the pin head. Big time. No imagination required. 3-5 feet per stagger. Fatheads were just smoother. And this was on a rig that DID NOT BEND.

I would never ever go back to a pinhead, especially in big winds. The closest I would go would be a highly roache pinhead, but if we keep Amati, I'm going from our current highly roached pin head ( looks like a Hobie 16 main) to a fathead or small squarehead. In 1999 I couldnt talk Lidgard into a fathead, and the pin head jerks around in higher winds. Bleah.

Paul
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  #94  
Old 02-22-2012, 09:01 AM
sailingdaniel sailingdaniel is offline
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Thanks all for great answers on this now old thread..

I have been sailing , sailing and sailing and havent had much time to think about design for a while.. I now reached Brasil and now i have time to relax and dream again !

I wasnt able to really test moving my cutterstay to leward as. The wind was not strong enough for my small cuttersail and whit waves and current i could not say if i helped ore not.. But i know for sure that it did not make anything worse so im optemistic..

But my genoa who was cut down from a low cut 150% to a high cut 110% was better in almost every wind then the "old" one and much easier to control.. In very light winds to windward the old big one was better.. I add a pic on that genoa and the alwaysaonthebeamperfectsailing i had in madagaskar..

An other intresting thing is whit the smaller 110 genoa is that i could sail faster on a broad reach whit the sail to windward whit the pool.. And i could go suprisingly "high" in the wind like this.

The answer about stay angel in my origenal question seams to me be: There is nothing "wrong" whit a stay angel of say 23 deg if the boat is long enough to find a place to fit the lower en of the stay.. And 0 ore 1 deg would be ok if it would not be to close to the mast and the mast would be strong enough !!! .. In other words, other things in the design seams to control the stay angle....

Cheers

Daniel
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