Reefing Claw

Moderator: GreenLake

Reefing Claw

Postby jcalvinmarks » Tue Jun 09, 2009 9:51 pm

Looking back through the posts, I see it's been a while since reefing claws have come up, so I thought I'd post this. I just bought one on eBay for $20. It's a 5" (128mm) aluminum claw. Not a normal auction; the guy has a "store" on eBay. There's still one left. The guy is asking $30, but he took my offer at $20, so if someone wants to get in there and pick up the other one, it's item number 350198025320.

I understand that the roller reefing feature is not optimal when compared to slab reefing or jiffy reefing, but I don't think I understand why it is inferior. Something about poor sail shape, but I don't understand how. I'm sure once I get out there and try it, I'll see exactly what the issue is. But my wife and I are not into racing (at least not yet), just out for pleasure, so for an inexpensive insurance policy against running into stronger winds than we had expected, I think (I hope) this will fit the bill.
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Postby GreenLake » Wed Jun 10, 2009 12:38 am

I wonder if you can have the benefit of both. Here's what I was pondering: what if you were to put a reefing grommet in the leech of your sail. That way, when the sail is rolled up to that point, you would have the ability to flatten the remaining sail by pulling it back (like an outhaul). Unlike slab reefing, you don't use a reefline to pull the sail down - that would be done by rolling it around the boom - but you would still have the ability to influence sail shape.

One downside of reefing claws is that they have to rest on the rolled up sail. That might cause some chafe (don't have practical experience and if I wanted to gain some, I would try it first on a set of old sails).

The sail is not a flat sheet of material, so rolling it up might shorten it in different ways than pulling on two precisely located reef points. I suspect that the loss of outhaul control no standard roller reefing is the more signfificant aspect. Perhaps someone can confirm this or provide a better story.
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reefing claw

Postby kokko » Wed Jun 10, 2009 9:14 am

I bought my '68 ds1 and it had th eroller boom but not a reefing claw.
In any discussion about the merits of roller reefing vs. jiffy reefing, the most important issue is the ability to reef. Remember, reef early.

So I have never had experience using the roller reefing on the DS1, but I have used it on other boats. My preference is for jiffy reefing, so I added the proper reefing grommets, reef lines and cleats to my boat.

Ideally you reef before raising the main, but it can be done easily undere sail as well. Loosen the main, bring the sail down to the reef points with the reef lines, cleat and put some additional tension on the main.

THe roller reefing is similar, except the mainsheet must be disconnected from the boom. Pull back on the boom, roll it up, connect the reef clamp and mainsheet, and tension the hailyard.

Both really require a topping lift.
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Postby jcalvinmarks » Wed Jun 10, 2009 10:27 am

That's an intriguing idea, to have an outhaul on a roller reefed sail! I suppose I'd either have to have a single reefing setting on the sail, or put multiple grommets on the leech.

But at any rate, old sails is what I've got. I'll report back on the stresses that the claw puts on a reefed sail next time I go out. Hopefully it shouldn't be too bad. In my mind's eye, the mainsheet pulls the claw at an angle so the opening points to leeward slightly, and it isn't bearing against the taut sail, just on the rolled sail on the boom (depending on which way you roll it and what tack you're on), but we'll see how that pans out.
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Postby seandwyer » Wed Jun 10, 2009 11:56 am

I don't understand what the claw does / how it works. I've even been on the ebay page to see what it looks like and I still don't get it. On further inspection, I think my boom does have that spring loaded roller reefing feature, but conceptualy, things aren't clicking for me.
Sean
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reefing claw

Postby kokko » Wed Jun 10, 2009 11:59 am

With you main rolled up on the boom, you cannot connect the mainseet to the boom as usualy. THe claw clamps around the rolled sail and boom and allows attachment of the mainsheet.
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Postby jcalvinmarks » Wed Jun 10, 2009 12:07 pm

Go down to the very bottom of this page:

http://www.gjenvick.com/BangorPunta/ODa ... ories.html

There's a picture of a reefing claw in action. The open end allows the sail to run up as it normally would, and the hole in the bottom attaches to the mainsheet block (which would be buried if you rolled the sail up without detaching it first. Just detach the shackle from its attachment point on the boom, roll the sail up, slide the claw down, and reattach the block. Or, I suppose, since it has the open end, you could slide the claw on the boom, detach the block from the boom, attach the block to the claw, then roll the sail up.

I would imagine it works best with mid-boom sheeting, but it could work with a stern traveler as well. If you have an additional block to run through on the way to the after end, you'll lose that functionality, as well as your outhaul, since those will be rolled up in the sail. You'll also have to detach your boom vang.

It's a compromise, to be sure. But this seems like the cheapest and easiest solution to get us back to the dock or to shore in case the winds pick up more than we're comfortable with.
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Postby GreenLake » Wed Jun 10, 2009 12:43 pm

jcalvinmarks wrote:That's an intriguing idea, to have an outhaul on a roller reefed sail! I suppose I'd either have to have a single reefing setting on the sail, or put multiple grommets on the leech.


You'd need a grommet and a patch of reinforcement to take the extra stresses on that point. A single point would be enough. The idea that you "continuously" adjust a reef is not realistic (unlike a roller furled jib), so you would pick a point about a foot or 18" up (adjusted to where the sail ends up after the corresponding number of turns on the boom).

If you need to reef further than that you'd rely on the boom alone, but hopefully that's a really rare situation. Unlike a slab reef system, you at least would have the option of reducing sail further.

jcalvinmarks wrote:It's a compromise, to be sure.


That is true in some sense for all reefing arrangements. None has the same ideal sail shape and well-balanced sail plan like the original unreefed sails. But they serve their purpose.
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confused about the roller reefing

Postby JML Avalon » Sun Aug 09, 2009 11:09 pm

Still new to my early ('72?) DSII (sail No. 4854), and was thinking about reefing today. I plan to try the roller reefing, but I can't figure out how to work the boom rotation. The connection between the boom and the gooseneck is a fitting with a pin. I can't find a way to rotate the boom without removing this pin, but then the boom is not attached to anything at all once except the sail once I disconnect the main sheet, and that can't be right, can it? Don't know if the boom is original, but it does have the attachment for the vang that I see pictured in Roger Conrad's book. Any help would be appreciated, and apologies if I'm missed this info elsewhere on the forums.
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Postby GreenLake » Mon Aug 10, 2009 12:02 am

I think it goes something like this:

You remove all fittings from the boom (except at the end).

You pull out the boom (against a spring), which lets it rotate.
The spring is inside the boom and pulls the gooseneck into
a square fitting, which prevents it from rotating unless you
pull the boom back

You use a reef claw to provide a place to which you can
attach the sheet.
(The claw needs to be held in position along the boom by a line.)

Lacking a claw, and feeling a bit dubious about the whole the concept, I decided to go for jiffy reefing instead...
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