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04-10-2014, 11:50
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#16
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Marine Service Provider
Join Date: May 2012
Location: New Orleans
Boat: We have a problem... A serious addiction issue.
Posts: 3,974
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Re: New Sails! Advice Needed.
Quote:
Originally Posted by Dockhead
The problem I guess is how much wind you need to move at a reasonable speed at these angles, so I guess a big sail which allows us to sail at lower wind speeds is the ticket, even if it can't be used all that deep.
With all white sails, we just put on the motor if there's not enough wind to drive the boat. I guess that's not the end of the world. Motor-sailing downwind in light wind is pleasant enough. But still, an assymetrical which increases the feasible wind range would probably be a good thing.
You didn't comment on the effect of using a pole.
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A wisker pole on an asym to be effective would need to be massive... Just roughly with a 20' J add another 5' for a sprint times about 1.7 gives a foot leingth for a genniker of about 42'. A reasonable wisker pole need to be the same leingth as the foot of the sail, so you are talking about a wisker pole almost as long as your boat. Though longer would be better.
The other issue is that a properly cut and trimmed genniker doesn't gain much from a wisker pole. Because of the nature of the beast they fly free of the wind shadow of the main, and since they are much lighter than a Dacron sail don't need the support. Unlike a genoa a genniker is cut specifically to be carried deep, which is what the shoulder is for, to help pull the leading edge of the sail to windward and keep it full.
__________________
Greg
- If animals weren't meant to be eaten then they wouldn't be made of food.
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04-10-2014, 13:18
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#17
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Moderator
Join Date: Mar 2009
Location: Denmark (Winter), Cruising North Sea and Baltic (Summer)
Boat: Cutter-Rigged Moody 54
Posts: 35,025
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Re: New Sails! Advice Needed.
Thanks, very useful information!
Quote:
Originally Posted by Stumble
A wisker pole on an asym to be effective would need to be massive... Just roughly with a 20' J add another 5' for a sprint times about 1.7 gives a foot leingth for a genniker of about 42'. A reasonable wisker pole need to be the same leingth as the foot of the sail, so you are talking about a wisker pole almost as long as your boat. Though longer would be better.
The other issue is that a properly cut and trimmed genniker doesn't gain much from a wisker pole. Because of the nature of the beast they fly free of the wind shadow of the main, and since they are much lighter than a Dacron sail don't need the support. Unlike a genoa a genniker is cut specifically to be carried deep, which is what the shoulder is for, to help pull the leading edge of the sail to windward and keep it full.
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04-10-2014, 17:47
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#18
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Senior Cruiser
Join Date: Aug 2009
Posts: 4,033
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Re: New Sails! Advice Needed.
Re poles:
If we are trying to sail particularly deep, we set the tack of the a-chute on the pole (in pretty conventional fashion) rather than try to pole out the clew. You only need a conventional J pole for doing this. I would guess you gain about 20 degrees of angle doing this.
If we are going to pole out the clew we use the 'code zero' (in quotes because it does not meet the racing half girth measurement but otherwise is functionally equal to a zero).
I will note I think you have gotten some 'incorrect' advice on this thread re "cruising zero's".
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04-10-2014, 19:05
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#19
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Marine Service Provider
Join Date: May 2012
Location: New Orleans
Boat: We have a problem... A serious addiction issue.
Posts: 3,974
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Re: New Sails! Advice Needed.
Call it what you want. A code zero is a specialized sail that is not a generic term. A lot of lofts try and bill a lot of different Asymetric sails as 'Code Zero's' but they aren't. Wether it measures in as such or not.
Since North Sails along with EF Language designed the first one, and named it, here is what North says about a Code Zero...
Code Zero asymmetrics fit effectively into the crossover gap between a genoa and the ubiquitous 3A asymmetric reacher. They provide additional power at approx. 40-degrees AWA in true wind speeds under 10 knots; conditions that are typically slow with conventional sails. Code Zeros have also proved effective for reaching in 15-25 knot winds at 80 to 90 degree apparent wind angles.
Or since they build a lot of them, this is from Quantum...
A Code 0 Can sail in about 40-70 Apparent Wind Angle (AWA) and in 0-11 Knots True (TWS).
Frankly though this is a terminology issue not a sail design one. I don't feel like a sail designed for upwind work is a real benefit to a cruising boat. Particularly one that demands very high halyard tensions to keep the luff tight. Having a sail designed for 135-165 AWA however I think is a great move. Whatever your sailmaker calls it.
__________________
Greg
- If animals weren't meant to be eaten then they wouldn't be made of food.
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04-10-2014, 19:17
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#20
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Registered User
Join Date: Feb 2011
Location: Texas, USA
Boat: Jeanneau 44DS
Posts: 269
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Re: New Sails! Advice Needed.
Quote:
Originally Posted by estarzinger
Re poles:
If we are trying to sail particularly deep, we set the tack of the a-chute on the pole (in pretty conventional fashion) rather than try to pole out the clew. You only need a conventional J pole for doing this. I would guess you gain about 20 degrees of angle doing this.
If we are going to pole out the clew we use the 'code zero' (in quotes because it does not meet the racing half girth measurement but otherwise is functionally equal to a zero).
I will note I think you have gotten some 'incorrect' advice on this thread re "cruising zero's".
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He asked about a code zero, not whatever you mean by your term "cruising zero". An A0 sail is cut and marketed to be a reaching sail. It sounds as if you are skilled enough into manhandling it into a downwind sail of sorts but that doesn't mean it's the best tool for Dockhead, especially if he wants a purely downwind sail. That's like me asking what's the best chisel and someone answering that the best is a flat head screwdriver because that's what they use.
Sent from my iPad using Cruisers Sailing Forum
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04-10-2014, 19:30
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#21
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Senior Cruiser
Join Date: Aug 2009
Posts: 4,033
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Re: New Sails! Advice Needed.
^^
Well . . . .
#1 when you sail thru a lull, the apparent wind comes forward. A zero can be trimmed to that, while deeper sails can not.
#2 the tensionned luff on a zero is much more stable than the "shoulders" on deeper sails, so it requires less attention.
#3 the straight luff makes for more trouble free furling, making the sail much easier to handle thru squalls
All three of those make the sail easier to handle than deeper sails.
#4 sure deeper cut sails are marginally faster than a zero cut when sailing deep, but it is really marginal in cruising terms and the above ease of handling is IMHO more important for a cruiser. With a zero you can pole either the tack or the clew if you want to go deep, and if you put a jib out in the other side you get almost the same projected area as a medium a-chute.
So, the speed loss is practically speaking really small.
#5 you do not need huge halyard tension on a zero, unless/except when sailing quite close (say closer than 50 degrees), and even this "huge" halyard tension is simply accomplished with a 2:1 halyard.
So there are no practical problems using a zero.
Net net we carry two a-chutes and a zero, and have really mostly given up setting the a-chutes because the zero is so easy to set and handle and its speed penalty is so small (in cruising terms).
Note: our zero is made from DP's VZ cloth, and cut like a racing zero except for the mid-girth measurement. That's what a mean by a "cruising zero". I do not mean some sort of gennaker. I have had /used zeros like this from Doyle, quantum and north. (we were, according to North, the first cruising boat in the world to use a furling zero; so I have a few years and miles refining/using this concept)
A racing sailor would look at all this differently because they have different priorities and an extra tenth of a knot is the essential priority.
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04-10-2014, 20:40
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#22
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Registered User
Join Date: Apr 2011
Location: Vancouver, BC
Boat: Niagara 35
Posts: 1,878
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Re: New Sails! Advice Needed.
That's a great summary, Evans. I'm starting to come around to the idea of a cruising code zero being a superior sail, especially offshore. I especially appreciate your comment on halyard tension not being so high downwind, as that allows you to put the tack on a pole, potentially. Is that really any better than winging out a jib on a pole to windward instead, though?
Dockhead, I once saw a main with the leech line lead up to a small pulley and then down the luff. This allowed the line to be adjusted easily and safely at the mast. I was really impressed by this, but I haven't seen it since. Maybe there's a disadvantage that I'm not aware of.
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04-10-2014, 20:54
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#23
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Registered User
Join Date: May 2007
Location: Currently East Coast USA/Caribbean
Boat: Stevens 47
Posts: 223
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Re: New Sails! Advice Needed.
Evans is spot on. The other descriptions of code zero look at the sail in a racing context. A cruising code zero is a different beast.
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04-10-2014, 20:57
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#24
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Senior Cruiser
Join Date: Aug 2009
Posts: 4,033
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Re: New Sails! Advice Needed.
Quote:
Originally Posted by cwyckham
>> Is that really any better than winging out a jib on a pole to windward >>instead, though?
The masthead A2 clearly benefits from tack on the pole squared a ways back. I don't truly know with the zero but I would guess you are right that jib to windward is better.
>> I once saw a main with the leech line lead up to a small pulley and then >>down the luff.
Our main's have always been set up that way. Leach line down the luff to jam cleats at each reef point. We have a 3:1 tackle in it at the head, to give some leverage on the pull down line, otherwise Beth could not pull it when reefs are in.
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04-10-2014, 22:45
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#25
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Registered User
Join Date: Apr 2011
Location: Vancouver, BC
Boat: Niagara 35
Posts: 1,878
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Re: New Sails! Advice Needed.
Quote:
Originally Posted by svTOTEM
Evans is spot on. The other descriptions of code zero look at the sail in a racing context. A cruising code zero is a different beast.
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Can you describe how it is a different beast? I believe heavier fabric and a fuller cut?
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04-10-2014, 23:30
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#26
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Registered User
Join Date: Jun 2014
Location: Up the mast, looking for clean wind.
Boat: Currently Shopping, & Heavily in LUST!
Posts: 5,629
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Re: New Sails! Advice Needed.
The original "True" Code 0's were racing sails which were developed to exploit a loophole in the racing rules for the VOR boats.
The boats were only allowed a certain number of sails by the class's racing rules, including a limit on the number of jibs/genoas. And of course, being racers, there was/is an endless quest for something new, which gives even the tiniest edge in performance.
So, the sailmaker(s) basically designed genoas with their own built in luff wire/headstay. Thus, since they weren't flown on a headstay, they weren't measured in under the rules as genoas.
The catch being, that in order to have any shot at some degree of upwind performance, they needed HUGE luff tensions. And when I say huge, I mean measured more in tons than pounds.
EF came out with them first, but before the boats even hit the docks by the end of the first leg when EF flew hers, everyone had them. Or their version of them. So they kinda' went from concept to production in 10 days give or take. And the idea, of free flying headsails optimized for wind forward of the beam, which could be flown from a furler drum, took off from there. Particularly as on those boats, & all of the big ocean racers since, almost without exception, sail with the apparent wind forward of the beam (or try to, mostly).
So in a nutshell, Code 0's (and their concept) began life as free flying genoa's. Upwind headsails which were designed from the outset never to be flown from a headstay. And to operate in the wind ranges as described above by Stumble.
Though to be honest, the concept's not new at all (just refined a bit), as with most things sailing, it's been around for hundreds of years (free flying headsails designed for upwind work).
PS: To fly one, & do it with a tight luff. If your halyard's strong enough, you can run the 2:1 purchase (or higher) at the deck level... the tack end.
__________________
The Uncommon Thing, The Hard Thing, The Important Thing (in Life): Making Promises to Yourself, And Keeping Them.
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04-10-2014, 23:54
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#27
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Registered User
Join Date: Jun 2014
Location: Up the mast, looking for clean wind.
Boat: Currently Shopping, & Heavily in LUST!
Posts: 5,629
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Re: New Sails! Advice Needed.
Quote:
Originally Posted by cwyckham
Can you describe how it is a different beast? I believe heavier fabric and a fuller cut?
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Read Evan's post/reply #21. And aside from that, what a "cruising code 0" is depends on whom you talk to.
You can have your sailmaker cut such a sail so that it's optimized anywhere from 045 degrees AWA, out to & beyond what a lot of folks would call an asymmetric spinnaker. And generally speaking, the deeper AWA it's designed for, the lighter the cloth, & the deeper the shoulder.
Also, whether or not it really needs a 2:1 on the halyard is open for discussion, & is based on; what AWA angles it's designed for, & what wind speeds you plan to carry it in. The closer to the wind, & the higher the planned wind range, the more likely it'll require some extra purchase on the halyard or at the tack.
In simple terms, and not to offend, think of a Code 0 as a AAA-cup, & a kite designed for dead downwind as a DD-cup. Both being loose luffed. And that the further off of the wind the sail's design optimized for, the bigger the "cup" it is/resembles.
To get an idea of kites designed for DEEP downwind sailing, pull up some pics of the 12m America's Cup racers. Like say the Freemantle era. They're cut about as deep as they come. And this is so that they were optimized for the; boats, courses, & wind speeds which those races were sailed in.
In pictures of them, you'll note that much of the time, if it's breezy, the spinnaker poles are pulled back pretty much all the way to the shrouds. And the mainsail booms are pushed forward to the other shrouds. So that'll give you an idea how deep AWA wise they were sailing.
__________________
The Uncommon Thing, The Hard Thing, The Important Thing (in Life): Making Promises to Yourself, And Keeping Them.
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04-10-2014, 23:57
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#28
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Registered User
Join Date: May 2007
Location: Currently East Coast USA/Caribbean
Boat: Stevens 47
Posts: 223
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Re: New Sails! Advice Needed.
cwyckham - Uncivilized has a very civilized overview code zero sails; and as he says the concept is much older than the current itteration - though much refined now. In the '92 AC I designed/built early versions of code sails for A-cubed; and they go back long before that.
As for the cruising version, design and geometry make them more forgiving/easier to fly; and tougher. They probably won't point as high as a racing version (depends on cloth), but that you can sail upwind to 65 or 70 degrees or far downwind (poled out) makes them more versatile than spin or A-sails. They're also easier to fly, being more genoa, less spinnaker like. They do give up a little performance to the sweet spot of a spin or A-sail, but cruising code zeros tend to get for more use than the other two. And getting used in this way is way they are nothing like a racing sail by the same name.
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05-10-2014, 00:30
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#29
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Registered User
Join Date: Jun 2014
Location: Up the mast, looking for clean wind.
Boat: Currently Shopping, & Heavily in LUST!
Posts: 5,629
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Re: New Sails! Advice Needed.
On leech cords, the gent has a good point, below. It's not a bad way to run things (having the leech cord run through a block at the top of the sail & then down to the tack). Though you have to remember to have a small jam cleat affixed to the main at each reef, so that any time you shorten sail (or vice versa), you can re-tension the luff.
Also, much of the time it's nice to have the leech cord terminate at the clew, via being tied through a grommet, which is affixed to a 2" wide piece of webbing with Velcro on it. The other side of the Velcro being sewn onto the adjacent part of the sail.
This, being done in conjunction with the above setup. Sometimes with a few other small tricks. Mostly ones, which if done correctly, will automatically handle most of the cord retensioning when you reef.
But yeah, it beats trying to reach a tiny piece of cord, out on the end of a wildly bucking boom, in order to re-cleat/re-tension things at the tack end when the wind's up.
Quote:
Originally Posted by cwyckham
That's a great summary, Evans. I'm starting to come around to the idea of a cruising code zero being a superior sail, especially offshore. I especially appreciate your comment on halyard tension not being so high downwind, as that allows you to put the tack on a pole, potentially. Is that really any better than winging out a jib on a pole to windward instead, though?
Dockhead, I once saw a main with the leech line lead up to a small pulley and then down the luff. This allowed the line to be adjusted easily and safely at the mast. I was really impressed by this, but I haven't seen it since. Maybe there's a disadvantage that I'm not aware of.
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s/vTotem, how ironic/small world. I guest crewed on the "B" boat in '92, & worked with the women for a while in '95.
__________________
The Uncommon Thing, The Hard Thing, The Important Thing (in Life): Making Promises to Yourself, And Keeping Them.
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05-10-2014, 04:01
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#30
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Registered User
Join Date: May 2007
Location: Currently East Coast USA/Caribbean
Boat: Stevens 47
Posts: 223
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Re: New Sails! Advice Needed.
1. Correct
2. Vectran is better -no creep.
3. Yes, and be sure clew block webbing is covered and that it’s sewn with PTFE thread.
4. No battens
5. No
6. Vectran overhead leech line with 2:1 purchase (at head) and cleat at tack. Vectran foot line with cleat at tack.
7. Sunbrella UV protection, on one side only and sewn with PTFE thread
8. Yes
Under the sailmakers statements, #5 is goofy because most of the sail is made in the lamination which they have no control over. Lamination is everything in the life of a laminate sail.
A few other things.
1. On main and yankee - tack and head “rings” of Spectra/Dyneema webbingloops.
2. Sewn seams should be with triple stitch, not zig zag.
3. Be sure to use plenty of sticky back under natural hinge point, because this is where laminations tend to fail first.
4. Specify or work with designer on yankee clew height. A very high clew on this rig is less efficient, and yankee heights vary a lot, so work it out before being surprised.
5. If you intend to furl reef (main and/or yankee), be sure the designer knows to include yarns oriented to handle furl reef loading.
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