how does one define a "blown out" sail?

[RussC]

I've only been sailing for about one year, perhaps 40-60 hours on the water. I started out with a Snark, which quickly grew to an AMF Puffer. the Puffer was a great sailing little boat, but the wife was pretty cramped when she went with me, so I picked up a really well kept, low hour, first generation Capri 14.2 for a very decent price. The wife is MUCH happier with the open cockpit design, and I like the boat a lot also, but frankly I think the little Puffer handled better and was faster all around.
Which bring me to my question. Granted, the sail on the Puffer was pretty new and a heavier material than the OEM sail on the Capri, but the Puffer sail could be flattened out into a pretty nice "wing", wile the Capri sail always has small bags and sags here and there, and seems to me to have excessive "bowl" in it. even when reefed tight, it's what I, as a beginner, would call "blown out". the photo is worst case, and obviously set loose, as my 105 lb wife doesn't have much strength for such things, but hopefully you see my point anyway.
So…. how is a beginner to know if a sail is truly in need of replacement….. or simply not adjusted correctly…. or even just designed that way to begin with? the sail material feels great to me, considering the age, and still has some resin in it, good stitching, very little fading, etc. How much "bowl" should this sail have??

Thanks,
Russ

 

[JohnVTX]

You appear to be at the top of the mast with the halyard, thus you cannot tighten it properly. You need to get the boom a little lower so the halyard can be tightened. If no adjustment to lower the boom, get a cunningham installed.

 

[shemandr]

To answer your question the "Bowl" of a main sail should be between 10 - 15%. This is according to Sail Smart Newsletter. 10% would be the flat-ish side for medium to fresh wind. 15% would be for light wind. So if you can flatten the sail to that 10% area it is likely tired. Of course these numbers apply to efficient upwind sailing.
I think modern sails are made more flat.

 

[RussC]

I am pretty close to the top of the mast with the halyard, but I think most of the small wrinkles you see are due to it not being sweated very well (I'm blaming my wife ). I actually adjusted the boom stop down about an inch last time ashore, but it may not have been enough. I hesitate to lower it more than needed, to conserve headroom with the sail flaked. there is a Cunningham, but I seldom use it to tune.
I guess I'm not understanding what is meant by "10-15%". 10-15% of what?

Thanks much,
Russ

PS: I guess I didn't mention, and it doesn't show well in my photo, but a lot of the belly, or bowl, I referred to is at the bottom part of the sail. I think this is referred to as the "shelf?". even with the outhaul and halyard tight there still seems to be quite a large belly there.

 

[JohnVTX]

You need to use cunningham to tighten the sail. It is very loose at the head of sail. This will help to flatten your sail.

 

[shemandr]

I guess I'm not understanding what is meant by "10-15%". 10-15% of what?

... of the length of the cord. That is the distance from the luff to the leech. If that distance were 10', then the belly should vary between 1 and 1.5 feet. That distance varies as one looks up the sail because of the triangular shape. Less chord depth (Not percentage) higher up.

 

[RussC]

... of the length of the cord. That is the distance from the luff to the leech. If that distance were 10', then the belly should vary between 1 and 1.5 feet. That distance varies as one looks up the sail because of the triangular shape. Less chord depth (Not percentage) higher up.

Awwww. Thank you for that excellent explanation shemandr.
now I need to set sail and do some more observing, measuring, and adjusting. with summer winding down, I just hope I can get out a few more times this year, as I'm hungry to learn. We're already dreading the long months in the no sail zone .

Russ

 

[Jackdaw]

Can a sail become 'Blown out'... too much camber that you cannot flatten?

Technically yes.

But practically no.

I say practically 'no' because the moment you show me someone replacing a 'blown out' sail for a new one, I'll find you someone willing to pay real cash money for that old rag.

This also points to that different people will have different definitions of 'blown out'. For me the bar is pretty high. Others less so.

But technically, you want/need to be able to flatten the sail. Flattening the sail de-powers it, and makes it work better in breeze. If you cannot flatten it below 10% of camber, you should start looking.

How to measure? Look up the sail from the boom. Best take a picture. Or use Norths Scantool.

This is the main that came with our First 260. A heavy north dacron that was in great physical condition (stitching, leach, resined cloth etc) but blown out. 16% was a flat as she would go, even will full backstay and outhaul. Its sailbags now.

 

[flynhi4u]

This thread should be a mandatory read for all newbies, like myself. If Jack's sail is "blown out" ours must have sailed through a nuclear detonation!! Can't wait for the new sails to get here, so I can learn how to sail our boat all over again!
Another great explanation Jack.

Sam in IN

 

[flynhi4u]

As a side item, our new sail will have a Cunningham, where as our current sail does not. Do I just need to install a small cleat on the mast to cleat that line off to?

Thanks
Sam in IN

 

[JohnVTX]

Depending on size of boat, you may need a pulley setup to tighten

 

[Davidasailor26]

Can a sail become 'Blown out'... too much camber that you cannot flatten? Technically yes. But practically no. I say practically 'no' because the moment you show me someone replacing a 'blown out' sail for a new one, I'll find you someone willing to pay real cash money for that old rag. This also points to that different people will have different definitions of 'blown out'. For me the bar is pretty high. Others less so. But technically, you want/need to be able to flatten the sail. Flattening the sail de-powers it, and makes it work better in breeze. If you cannot flatten it below 10% of camber, you should start looking. How to measure? Look up the sail from the boom. Best take a picture. Or use Norths Scantool. This is the main that came with our First 260. A heavy north dacron that was in great physical condition (stitching, leach, resined cloth etc) but blown out. 16% was a flat as she would go, even will full backstay and outhaul. Its sailbags now.

Jackdaw, I've seen you reference the North tool before, but it looks like it's no longer available in the Apple App Store. Do you know where it might still be available?

 

[Jackdaw]

Jackdaw, I've seen you reference the North tool before, but it looks like it's no longer available in the Apple App Store. Do you know where it might still be available?

Ugh. It does seem to be gone. I can find references to it on various North sites, but none of the links to itunes work. They must have stopped supporting it. I know North Sails GMBH (Germany) created/commissioned it, and maybe the mothership decided it didn't want that power in the hands of the people. Oh well! Maybe I'll ask Ken! ;^)

Interestingly enough, mine is version 1.1, copyright 2011-2014. So availability and support did not stop too long ago!

Now I'll be totally careful about not deleting it. It is a great app and I use it all the time. I'm happy it runs on iOS9!

http://www.sail-world.com/North-Sails-Scan---iPhone-iPad-App-now-available-in-New-Zealand/87660

 

[RussC]

Well…. I did some yard sailing today. no matter how tight I reef the halyard, out haul, cunningham, etc, I couldn't get under 12-14% even in the 2-3knott wind in my yard. I know it doesn't make sense, but I just hate to give up on my stylish OEM sail but it looks like I'll have to. I wonder if North Sails would duplicate my colors.
One more question/observation. I notice when I pull down the cunningham it does tighten the sail a bit, but then begins to just raise the boom in the mast slot. seems like the way I sometimes use it, by just going directly to the cleat from the boom works better by pulling the boom down, thereby tightening the sail (sail foot bolt rope is in boom slot).
what am I missing here?

Thanks for all the willing assist. great forum knowledge :thumbs:

Russ

 

[Joe]

Well…. I did some yard sailing today. no matter how tight I reef the halyard, out haul, cunningham, etc, I couldn't get under 12-14% even in the 2-3knott wind in my yard. I know it doesn't make sense, but I just hate to give up on my stylish OEM sail but it looks like I'll have to. I wonder if North Sails would duplicate my colors.
One more question/observation. I notice when I pull down the cunningham it does tighten the sail a bit, but then begins to just raise the boom in the mast slot. seems like the way I sometimes use it, by just going directly to the cleat from the boom works better by pulling the boom down, thereby tightening the sail (sail foot bolt rope is in boom slot).
what am I missing here?

Thanks for all the willing assist. great forum knowledge :thumbs:

Russ

Cunningham should not be attached to boom.... attach to mast below the boom, removing it completely from any affect on luff. There is some variation in configuration and amount purchase you desire. Tie the boom off to the cleat or use a track stop to lock it in place.

On boats with attached foot sails, where the boom was routinely removed for trailering.... they often rigged with a "boom downhaul" . This not only kept the boom in place, it allowed you to impart some luff tension when you pulled it down. The Cunningham is a far superior trim device though.... I disabled my boom downhaul as soon as I acquired my boat... all I did was get a Cunningham hook to attach to the sail's cringle.

 

[RussC]

The manual I got with the boat shows the cunningham attached to the gooseneck, up through the cringle and down to the mast mounted cleat. doesn't mean that's the best way to do it however, as you're right, it sure isn't very effective that way.

R

 

[danstanford]

The manual I got with the boat shows the cunningham attached to the gooseneck, up through the cringle and down to the mast mounted cleat. doesn't mean that's the best way to do it however, as you're right, it sure isn't very effective that way. R

Because of the shape of the end of my boom, I have room to simply run the line from the cringle straight down to a block at the mast plate then back up to a cleat on the mast. I next want to run it back to a cleat or clutch at the cockpit so I can adjust easily. Going to do the same for my out haul but am going to need two more clutches I guess. Hopefully I can find something to replace the 3 line ones I have without too much more work on the deck. Having had a boat with water penetration then freezing in the deck I am loathe to make more holes!

Dan

 

[shemandr]

Well…. I did some yard sailing today. no matter how tight I reef the halyard, out haul, cunningham, etc, I couldn't get under 12-14% even in the 2-3knott wind in my yard. Russ

While you're in the yard ... I would see if you can put some bend in the mast. It seems from the first picture that the sail is crying for some mast bend. You probably don't have a back stay. But, if you're spreaders are swept back, which would be the case without a backstay, maybe you can put more tension on the shrouds which may induce some bend. Worth a try.
How does the boat sail?

 

[RussC]

While you're in the yard ... I would see if you can put some bend in the mast. It seems from the first picture that the sail is crying for some mast bend. You probably don't have a back stay. But, if you're spreaders are swept back, which would be the case without a backstay, maybe you can put more tension on the shrouds which may induce some bend. Worth a try.
How does the boat sail?

[disclaimer] My points of reference are pretty limited due to my lack of sailing experience. the only other sailboat I've sailed was the AMF Puffer for a couple months (20-30 hours sail time). Laugh if you must, but I gained a pretty good understanding of sail design due to my 2200+ hours of flying hang gliders for 18 years, which was also a great way to learn about wind and weather conditions btw….. anyway… with that in mind, the sailboat feels like the wing is partially stalled. I just can't seem to get the sail adjusted to where it feels "free" and attaining the boat speed that I think it should. visually, the sail doesn't look flat enough to me, but mostly it's just my seat of the pants sensation of having a drogue chute out. I think I do ok with it as far as pointing goes, and I like to play with staying right on the edge of the no sail zone.
As an aside: when a gust comes along it's easy to steer into it and gain a big boost in speed and pointing ability. as the gust eases, I find I have to turn off the wind a bit to keep the sail from luffing. is this typically the way this should work?
I did try playing with shroud tension and mast rake a wile back, but didn't find any big benefits that I could quantify here. in fact, overall, this boat seems to like having the shrouds a bit loose, and other 14.2 owners, as well as Catalina itself, seems to back up that assessment as correct. The boat (jib) likes the mast raked a bit forward when going downwind, and a bit back when into the wind. the 14.2 just has 2 shrouds and a forestay, so actually bending the mast is not an option.
If the suns comes out later today we may head to the lake for a bit. I'll let you know if I've learned anything from all this

Russ

 

[Jackdaw]

As an aside: when a gust comes along it's easy to steer into it and gain a big boost in speed and pointing ability. as the gust eases, I find I have to turn off the wind a bit to keep the sail from luffing. is this typically the way this should work?

While a LOT of people do it this way, its actually backwards.

When a puff hits you, it makes you heal mostly not because the increase in pressure, but because the apparent wind went AFT. That's why turning up helps, as it puts the apparent back to where the sails are trimmed. But what you should really do (in particular in a small boat) is to EASE the sail to match the new apparent, and then if the puff lasts slowly trim in as you turn up. This is better technique and much faster in average VMG. If you ever watch two identical boats go upwind, the one doing the ease-trim crushes the other boat.