Confused

HuronBouy

Anarchist
799
53
Canada
Ok 

I am a bit embarrassed to ask but here goes. 

I went to J school a number of years ago and went out on a J-80, put up asym and I  let the tack out (not alot) my instructor said "no tack must hard down on the bowsprit". But then I see lots of photos with tack eased.  It seems to me it must be a point sail thing but I see tack out at about 100 degrees and tack out a deepish. I can guess that for higher angle when "reaching" tack down may be correct and let it out to float  sail in deeper conditions but why dis this guy tell me this I don't get it.   

 
"More wind, more tack"

Pressure causes the forward edge of the sail (luff) to collapse. So as the wind picks up, you need a tighter luff - i.e. A tighter tack.

But when there is no pressure (i.e. less wind), you can relax the tack a bit and allow the entire kite to rotate to windward. Again, this is only possible with low pressure otherwise the wind will do the opposite and actually rotate the kite to leeward... and of course collapse as the luff will not be as tight as mentioned above.

~him

 

ctutmark

Super Anarchist
1,739
279
PNW
If the tackline is vertical or to windward when eased, fine. You don't want it to go to leeward. Easing the tack will make the sail more unstable and less forgiving to carrying a curl, so may not be faster. 

 
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very much depends on the boat, the sail, the wind speed, etc. I think it used to be more prevalent, but as shoulders get bigger and broader it is less useful. Certainly, it is less useful on faster boats. 

General rule of thumb, if the tack floats to leeward then you need to tighten it back in. However, depending on the cut of the kite, it may be completely useless/slow to let the tack float up even if it is rising straight up off the sprit. Talk to your doctor sailmaker to see if floating the tack is right for you. 

"More wind, more tack"

Pressure causes the forward edge of the sail (luff) to collapse. So as the wind picks up, you need a tighter luff - i.e. A tighter tack.

But when there is no pressure (i.e. less wind), you can relax the tack a bit and allow the entire kite to rotate to windward. Again, this is only possible with low pressure otherwise the wind will do the opposite and actually rotate the kite to leeward... and of course collapse as the luff will not be as tight as mentioned above.

~him
That is... not true. The only time i ever floated the tack on the 109 was when we had up the class kite (small sail) and were running deep AWA in bigger breeze. It's all about AWA, nothing to do with pressure. In light wind, you generally want it boned on since you'll be sailing hotter angles trying to keep the boat moving. 

 

sinker

Member
62
3
"More wind, more tack"

Pressure causes the forward edge of the sail (luff) to collapse. So as the wind picks up, you need a tighter luff - i.e. A tighter tack.

But when there is no pressure (i.e. less wind), you can relax the tack a bit and allow the entire kite to rotate to windward. Again, this is only possible with low pressure otherwise the wind will do the opposite and actually rotate the kite to leeward... and of course collapse as the luff will not be as tight as mentioned above.

~him
24-86-pull-midvale-school-for-the-gifted-30494358.png


 

From the Helm

Anarchist
555
21
Michigan
Much has to do with the boat and class sails vs. PHRF sails.   On the J105 the class kite responds well to an eased tack when you are able to maintain speed and sail deeper than you could with the tack boned on. The J105 PHRF kite has a longer luff and more area, flies well and deep with tack tight. 

J80 I believe has a more broad shouldered-ample luff length kite that may not be any faster nor deeper sailing when eased.  I raced one for a summer and don't recall ever leaving kite eased on tack.

How about easing the halyard when you need to get extra high, that's a neat trick, works well to get up over a competitor or when you need to tight reach to a finish line in a distance race.  Main still works well without the kite backwinding it and you can stand the boat back up a few degrees.

 

ryley

Super Anarchist
5,459
638
Boston, MA
J80 responds well to an eased tack, especially when trying to get low. Usually the tack shouldn't be eased more than the height of the bow pulpit. It's most useful in sub-planing conditions, but before it's so light that you have to sail hot angles. North's guide recommends 12-18" max ease on the tack line. You have to try to get some windward heel in order for the sail to roll out.

 
The answer is most definitely it depends... on a lot of factors. But for a semi displacement boat VMG running, the general rule of thumb is that if the take is pulling straight up or to windward, ease it out, but not an extreme amount. Depending on the boat and conditions, crews I've sailing with will grind the tack back down before a gybe to prevent fouling/give more stability for it to fill on the new gybe.

 

Dave S

Member
372
132
At one point on the I14 we were using kites with a cunningham. Leave it off for normal sailing, crank it on to flatten the luff when struggling on a tight reach. Worked really well with that particular cut of sail, we even managed to tack the thing in very light winds...

 

10thTonner

Hazard to Navigation
1,524
531
South of Spandau
Going deep in sub-planing conditions on a j/70, we ease the tack a little. I believe it helps the kite to set fuller and rotate a little to windward... but honestly, we didn’t do any boat-to-boat comparison. 

 
I just had this discussion with my sailmaker.  My last boat needed the tack eased a foot or so, the new one needs to be tight down (almost) always.  At least in my case the old boat had one design sails so it was limited to a specific sized kite thus for better performance it was designed to sit higher off the sprit and theoretically give more sail area higher up and better projection.  Our new boat isn't limited to a one design sail size, just rig measurements so it's designed to go all the way down to the sprit.

 
"...so we generally sail with the tack line eased. This helps rotate the chute to windward—a good guide is not to ease it more than the height of the pulpit. As the breeze builds, you may trim down the tack line to within a foot of the pole... The key transition downwind is in 9 to 11 knots, learning when you can sail deep and when to keep the boat sailing higher and faster. The tack line on the spinnaker is a good focal point for this: If the tack moves to leeward of vertical, pull the tack line toward the pole; if to weather, ease it out, with a total range of two or three feet. "

image.png

https://www.northsails.com/sailing/en/resources/j-105-speed-guide

 
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From the Helm

Anarchist
555
21
Michigan
"...so we generally sail with the tack line eased. This helps rotate the chute to windward—a good guide is not to ease it more than the height of the pulpit. As the breeze builds, you may trim down the tack line to within a foot of the pole... The key transition downwind is in 9 to 11 knots, learning when you can sail deep and when to keep the boat sailing higher and faster. The tack line on the spinnaker is a good focal point for this: If the tack moves to leeward of vertical, pull the tack line toward the pole; if to weather, ease it out, with a total range of two or three feet. "

View attachment 305489

https://www.northsails.com/sailing/en/resources/j-105-speed-guide
J105 speed guide.  Does the J80 say the same?

 

evenflow

Member
217
4
Toronto
I first sailed an 80 in SD and the instructor said keep it slack and if you’re doing it right the sail will pull to windward.  Now that I own one we follow the trim guide each sailmaker has one.  I’d simply do that as the trim guides are all a tad different but work like a charm.  

 
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