When NOT to use full length battens?

[Zed]

I'd have thought that if you are sailing a boat that has to drop backstay tension to tack the main it would likely be fractional, then either the caps keep fore stay tension or you have runners... either way you are talking about a racing boat IMO.

[CT 249]

Originally Posted by bistros

You have to live here to believe it. Snipes, Lightnings and Wayfarers abound and there isn't a B14, Tasar or Cherub to be found. Since you live the southern hemisphere and apparently haven't had to watch 1930's boats drift around the lake as the biggest fleet, your comments only apply locally.

Enforcing ancient fleet solidarity and killing off new high performance boats is a revered art form and popular social event here in North America. It never fails to amaze me that the most active I-14 fleets in North America are here in Toronto, Ottawa and New England - and the midwesterners are still sailing Flying Scots, Thistles and Buccaneers. I sail out of the largest club in the area, and there is more Dacron here than laminates.

The main sail roach measurement issues I was referring to was particular to the I-14s - they only recently agreed upon roach measurement standards at the last worlds in Sydney if I recall correctly. We've got everything from One Design 14s to B5s at our club and you can quickly see the sail area progression over time as you look at sails laid out on the ground. My thesis about development classes growing sail area & aspect ratio using full battens is pretty well borne out by the range of boats I see here.

Be glad you live in a modern part of the world where skiffs aren't thought of as tools of the devil for crazy folks. You are lucky!

--
Bill

Jim's right, there were fully battened mains in development classes and some one designs here in Australia and in Europe for many years before particularly large roaches came along.

I think you'll also find that automatic depowering in bermudan rigs really came to the fore in short-battened classes, namely Stars, Swedish canoes and their descendant, the Finn.

[gonzo]

Originally Posted by Paul B

I don't want to win, or even participate in an argument. But someone has to step in when someone like you simply makes things up. You seem to do this often. You should learn to sail before calling me a liar.
You claim that most boats with full battens were not designed for them. That has nothing to do with me knowing to sail or not. It is just a false claim.



Most keelboats I have sailed with full battens have NEVER had any issue with loosening of the forestay during a tack (loosening is actually beneficial when it is light and/or lumpy, the reason we make sure not to trim on the runners too quickly in racing boats). The thing you can't seem to understand is in monhull keelboats there are more pinhead mains that fit nicely through the backstay that have a full batten for the upper two battens than there are fully top-to-bottom battened sails. My boat, for example, has a pinhead main with two top full battens and it tacks and gybes through the backstay with no more effort than a sail without any full battens. There are thousands of sails out there just like it, most on boats that started life without any full battens.

In any rig where the forestay is at the top of the mast, loosening the backstay will loosen the forestay too. My answer to that would be hundreds of boats.

What boats have you sailed where the forestay has loosened on each tack?

All the boats with masthead rigs if you loosen the backstay


Some of us who know how to sail do actually use the vangs on our boats, regardless of whether our battens are full or not. By the way, the vang's purpose is to control twist.

With extra roach the vang tension has to be higher to control twist


By battens?

?


Please tell us ONE instance where a mast was broken by the force of battens!

Read my post. It is the extra compression on the mast by the boom. That is the main cause of broken masts during jibing.

[Paul B]

Originally Posted by gonzo

Read my post. It is the extra compression on the mast by the boom. That is the main cause of broken masts during jibing.

Your posts get more and more bizarre.

OK, please tell us ONE instance where the load on a boom was increased by adding full battens, so much so that the mast broke in a gybe because of the addition of full battens to the sail.

[kim s]

I am fearfull of saying much here in case I get my head bitten off
I am a confirmed Expereinced cruising sailor and a keen novice w/e racer (what I lack in ability I make up for in enthusiasem.) I "thought" that one of the problems i have with fully battened is that once the batten tension is sett, then it is difficult to change the camber on the sail unless you have some serious purchases in place. for the average Joe with his solid family long keel boat then the only benifit IMHO is the lack of flogging/sail handling etc, On more racy machine, fractional rig and sett up for it (retro fit or otherwise) then I have seen huge benifits.
I have a fellow club member who fitted a full system at huge expense and was very disapointed that he did not win everything in site.
I did try to help and with the added tackles and more purchase managed to get a bit more out of it , But in relation to the amount of money spent. a good sett of standard sails would have given better performance.
Again this might be just down to ignorance on my part.
If any one could explain if I am wrong, then this forum has once again come up trumps and I will toast everyone when I pick the silverware

[powerabout]

full batten mains are harder to depower then ones without full battens
no-one seems to have mentioned that

The posts seem to have ended up taking about full roach sails hitting the backstay but I dont see where he said the type of sail plan or rig he had?
I have a big roach fully battened main on a bolt rope but swept back spreaders so no back stay..easy
Hunter production boats have that as well too think of one.

You could have a split back stay as well?

[powerabout]

Originally Posted by gonzo

Read my post. It is the extra compression on the mast by the boom. That is the main cause of broken masts during jibing.

I see what your saying, vang holding sail twist as main sheet has been released ( no curved track and DDW to boom going out a long way) so vang pulling boom with enourmous force into mast.

( My Magic 25 has 2 rigging wires from the goose neck to the deck to prevent that happening. Early boats did break some masts when pumping the vang downwind)

[powerabout]

Originally Posted by Zed

I'd have thought that if you are sailing a boat that has to drop backstay tension to tack the main it would likely be fractional, then either the caps keep fore stay tension or you have runners... either way you are talking about a racing boat IMO.

I did a regatta on a Swan 80 a few years back and we had to drop the main down a foot on each tack and then back up....nice not!
22 crew no prob.

[Steve W]

Kim B,As Paul B said,having full length top battens is pretty much the norm these days but all full length you see more on cruisers for handling reasons rather than performance.Unfortunatly its those top ones that have the backstay clearance issues.
Steve

[gonzo]

In a sail with no battens, the tension on the vang is minimal. Just enough to keep the boom from kicking up. With full battens, the boom needs to be kept down with more tension, which creates more compression sideways on the mast. The area around the gooseneck is where masts usually break during jibing.
Paul: the battens do not add tension, but to keep them from wrapping around the shrouds it is necessary to tension the vang more. With few exceptions there is no support for the mast at the gooseneck.

[Paul B]

Originally Posted by gonzo

Paul: the battens do not add tension, but to keep them from wrapping around the shrouds it is necessary to tension the vang more. With few exceptions there is no support for the mast at the gooseneck.

Believe it or not, I know how a vang works. I also know that people who know how to sail use their vangs, regardless of the type of mainsail they use. I also know that having the vang on does not break a keelboat's mast at the gooseneck during gybes (unless the mast was deficient in the first place).

In fact, in almost 40 years around the scene and over 10 years actually working in the industry I have never seen a keelboat's mast broken off at the gooseneck due to vang loads. When you consider I started in the industry working for one of the larger spar builders at the time I might add I always take note when I see a broken spar, to deteremine the root cause of the issue.

So you have claimed on this thread that you have seen retrofits where the mast broke because the boat changed to full battens. You've had three opportunities to tell us specifics, and yet you cannot.

[Paul B]

Originally Posted by powerabout

I did a regatta on a Swan 80 a few years back and we had to drop the main down a foot on each tack and then back up....nice not!
22 crew no prob.

Sound like pretty poor sail design there. Normally if a crewed racing keelboat has a huge roach they go with dual backstays, as used on the IACC boats and even the OD48 I have spent time sailing.

Which Swan 80 was it?

[Paul B]

Originally Posted by powerabout

full batten mains are harder to depower then ones without full battens
no-one seems to have mentioned that

Funny, most people find just the opposite is true.

[CT 249]

Originally Posted by kim s

I am fearfull of saying much here in case I get my head bitten off
I am a confirmed Expereinced cruising sailor and a keen novice w/e racer (what I lack in ability I make up for in enthusiasem.) I "thought" that one of the problems i have with fully battened is that once the batten tension is sett, then it is difficult to change the camber on the sail unless you have some serious purchases in place. for the average Joe with his solid family long keel boat then the only benifit IMHO is the lack of flogging/sail handling etc, On more racy machine, fractional rig and sett up for it (retro fit or otherwise) then I have seen huge benifits.
I have a fellow club member who fitted a full system at huge expense and was very disapointed that he did not win everything in site.
I did try to help and with the added tackles and more purchase managed to get a bit more out of it , But in relation to the amount of money spent. a good sett of standard sails would have given better performance.
Again this might be just down to ignorance on my part.
If any one could explain if I am wrong, then this forum has once again come up trumps and I will toast everyone when I pick the silverware

For my 2 cents worth, you're only 'wrong' in lumping all fully battened sails together. As we all know, they can vary from conventional small-roach sails that have just had lightweight battens retrofitted to reduce flogging and make stowage easier, to high-load squaretops that require immense mainsheet tension when set on stiff masts. As you said, with some designs there can be limits on shifting the draft, but not with all types of fully-battened sail.

I certainly wouldn't say that a good fully-battened sail is harder to depower when sailing (if worst comes to worst you can twist them off without flogging) but the fact that they can power-up even when the sheet is fully eased can be a problem in some craft when coming into start lines and in other very low-speed situations.

[powerabout]

Originally Posted by Paul B

Sound like pretty poor sail design there. Normally if a crewed racing keelboat has a huge roach they go with dual backstays, as used on the IACC boats and even the OD48 I have spent time sailing.

Which Swan 80 was it?

Sayonara

You take a hit on IRC for split backstay I am pretty sure so the config was a rating thing.

Light breeze is when you have a prob, 15kts+ no prob