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Old 16-10-2008, 04:19   #1
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Makeshift Jib Reef

I had an idea for a way to reef some square footage off a jib. I wondered if this is something people do sometimes and, if not, why not. I can't sleep and was wondering...

You take a line with a loop at one end. The loop is maybe 12inches or so. The length of the line is variable depending on how much reefage you want. The loop goes around the sail at the clew. The bitter end goes to the forestay, through a shackle, down to the tack, through another shackle, then to the mast. Then the line is pulled at the mast which moves the loop towards the forestay and forcing the sail through the loop which sort of "marries" the foot and the leach on the clew side of the loop. Now the location of the clew (from the perspective of sail shape) has moved towards the luff. The sail area is reduced.

black is the forestay
blue is the sail
yellow is the reefing line
purple are jiblines
green is the shackle
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Old 16-10-2008, 04:26   #2
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Interesting idea. I think you will kill the shape of the jib. Try it and I think you'll see that's the case.

Also your drawing shows a fairly equilateral triangle. In reality the leech is much longer than the foot. So what you will reduce to is a very long, high aspect ratio sail that I don't think will work well.

Have you looked for a used storm jib? Could pick a used one up cheaply.
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Old 16-10-2008, 08:00   #3
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I have a 65% or 70% that I call my storm jib. I explained this to a guy once who said "Oh I have a brand new storm jib I can sell you cheap!" so we dug it out of his storage and I insisted on pulling it out of the bag and checking it out... It was at least an 80%.

This wasn't a plan I concocted to accomplish something- it was just mental wandering. I agree you would wind up with a poorly shaped and high on the stay sail. Hhhmmm... This would not address the shape issue but I guess you could just do a loop up from the tack and over the leach. That would at least leave the bulk of the material lower.

Maybe I will experiment and see if this works en route.

You know, after I finish the wiring and the bimini and the refrigerator install and the stereo and the bookshelf and the head rebuild and the mast light fix and...
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Old 16-10-2008, 08:26   #4
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If this is a hanked on sail, the best way to reduce it, is to add an additional cringle a couple of feet up the luff, plus another cringle (reinforced) the same distance up the leach. Thus when reefing, you lower it, attach to the new cringle at the foot of the sail, and move the sheets to the new cringle on the leach. Roll up the residue and secure (thus you will need some reefing points as well!) This will reduce the size of the sail, and lower its centre of effort, but will not wreck the shape of the sail,
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Old 16-10-2008, 11:51   #5
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If this is a hanked on sail, the best way to reduce it, is to add an additional cringle a couple of feet up the luff, plus another cringle (reinforced) the same distance up the leach. Thus when reefing, you lower it, attach to the new cringle at the foot of the sail, and move the sheets to the new cringle on the leach. Roll up the residue and secure (thus you will need some reefing points as well!) This will reduce the size of the sail, and lower its centre of effort, but will not wreck the shape of the sail,
Reefing jibs as Talbot describes are not a new idea, they've been around forever. A good, simple practical solution. There is no reason it couldn't work with a roller furling jib, and give you a better sail shape than with roller reefing. Of course you could not roll up the reefed sail...

Some jibs were even made with zippers so you just removed the bottom of the sail when reefed.

Jack's original idea at the top of this thread will not work. Besides being VERY hard on the sailcloth, it would result in a great big bag instead of a flat sail. You don't need to try it with a sail, just use a napkin in your hand...
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Old 16-10-2008, 17:33   #6
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Some jibs were even made with zippers so you just removed the bottom of the sail when reefed.
I have a pair of pants like that. I like to zip off one leg only and go to lunch at the club and tell teh story 'bout how the shark almost got me.
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Old 24-10-2008, 19:13   #7
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Why not just use a tarp clamp on a spot with a protective pad or tab sewn on? Tarp clamps work, are cheap, and are very easy to use. They also allow you to reef to whatever level is needed.
I am a beginner and know nothing pretty much. This is what I was planning to do instead of adding reefing grommets.
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Old 26-10-2008, 17:48   #8
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Why not just use a tarp clamp on a spot with a protective pad or tab sewn on? Tarp clamps work, are cheap, and are very easy to use. They also allow you to reef to whatever level is needed.
I am a beginner and know nothing pretty much. This is what I was planning to do instead of adding reefing grommets.
The "grommet" needs to be in an area that is reinforced.
One cannot just add one somewhere and expect it to have strength in wind conditions that require reefing.
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Old 27-10-2008, 08:42   #9
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Soon we should be hearing from Jack. Hopefully all is well, and there hasn't been mutiny aboard.
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Old 01-11-2008, 04:19   #10
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Reefing jibs as Talbot describes are not a new idea, they've been around forever. A good, simple practical solution. There is no reason it couldn't work with a roller furling jib, and give you a better sail shape than with roller reefing. Of course you could not roll up the reefed sail...
I have such a jib that came with my boat. I am reluctant to use it on my roller furler for fear that the large grommet at the reef tack point would damage the roller-furler's foil if the sail were to be tightly rolled up.

Also, the ISAF Offshore Special Regulations no longer allow the use of jibs with reefs in them to satisfy the requirements for having heavy weather sails on board. I have heard that this is because the bundle of fabric that would be the foot of a reefed jib has a propensity to catch waves and thus unduly burden the boat just at a time when that should be avoided.

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