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Old 26-05-2009, 18:11   #16
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If it is deck stepped will the base take the load if the blocks are on the mast versus the deck?
From a design standpoint the answer always is yes. The loads on the blocks are set up for more than you could expect. It's why the SWL (safe working load) is much smaller than the breaking strength on everything. You can always have a load failure for unusual situations.
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Old 26-05-2009, 18:14   #17
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What I was wondering Paul is can the butt take the shear load. If the block is bolted to the deck the butt does not see a shear only a compression. If the block is bolted to the mast the butt sees shear. What is holding the butt in place?

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From a design standpoint the answer always is yes. The loads on the blocks are set up for more than you could expect. It's why the SWL (safe working load) is much smaller than the breaking strength on everything. You can always have a load failure for unusual situations.
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Old 26-05-2009, 18:21   #18
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Mine is simple - horn on each side of gooseneck to hook in reef eye at luff and reefing lines to cockpit. I simply let the main luff then lower it enough to put eye on horn which does require going to the mast and then from the cockpit tension halyard and reefing line. Very quick and easy.
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Old 26-05-2009, 18:32   #19
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Porto - just wondering, and trying to learn as well. Why do you have to go to the mast, to hook the reef point on the luff?

Could you not (if you wanted to) run another reef line from the boom, up through the reef point, down to a block (or two) and then back to the cockpit as well. This is how I have it setup on mine, and it works well for me. There were no reef hooks on / near the gooseneck, so I ran the lines as mentioned. I have another that tightens the clew, down and back, and also runs to the cockpit. I like not having to go to the mast.

Unfortunately, I do have to go to the mast to put a second reef in, as the bottom 5 slugs are on a jackline, and the 2nd reef point will not reach the gooseneck, without taking out the bottom slugs, or untying the jackline, to allow enough slack so that the reef point will go low enough. I would like to change that somehow, if possible.
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Old 26-05-2009, 18:46   #20
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What is holding the butt in place?
The SWL of the block says to me it will fail first. The deck and mast should handle far more than those loads. It is possible to have a swiss cheese mast with too many holes or a deck with not enough backing plate. I believe the rule for blocks is 7 times the diameter of the line. If the line was 10mm you want 70 mm blocks and to be that says 2000 lbs SWL. You can buy big blocks with 1000 lbs SWL (Ronstan and Schaefer sell them), but they fail easier. I've has 1000lb blocks fail and the sheave shear. It was in a case where it was old (hey it all gets too old some time) but the line wedged in the cheeks and was not something you could deal with in 30 knot winds. Lucky for me the reef was almost set. It could have used a few more inches on the reef line but I wasn't going to get it set in those conditions with the line wedged in the cheeks. In that case the block failed far sooner. I eventually replaced all the foot blocks on the mast.
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Old 26-05-2009, 19:07   #21
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It's usually true on all boats. When the sail loads are higher the slack in the luff is sucked up in the sail and does not make it drop on it's own weight. It needs something to pull it down.

The reef line (led to the cockpit) pulls it down. Slack the Halyard to the mark for the first reef amd engage the clutch, put the reef line around the cabin top winch and crank er down. pulls the tack and the clew at the same time. Since the halyard is marked I don't even need to retension the halyard after the reef is in.
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Old 26-05-2009, 19:17   #22
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Porto - just wondering, and trying to learn as well. Why do you have to go to the mast, to hook the reef point on the luff?

Could you not (if you wanted to) run another reef line from the boom, up through the reef point, down to a block (or two) and then back to the cockpit as well. This is how I have it setup on mine, and it works well for me. There were no reef hooks on / near the gooseneck, so I ran the lines as mentioned. I have another that tightens the clew, down and back, and also runs to the cockpit. I like not having to go to the mast.

Unfortunately, I do have to go to the mast to put a second reef in, as the bottom 5 slugs are on a jackline, and the 2nd reef point will not reach the gooseneck, without taking out the bottom slugs, or untying the jackline, to allow enough slack so that the reef point will go low enough. I would like to change that somehow, if possible.
Good call - I have many lines running aft now - spare halyards, reefing lines, topping lifts, outhaul I didnt want to add to the list and for me (fit and young haha) it seems easy to just hook it at the mast - same system for the three reefing lines (Though for around here I only usually have the first set up. It is an IOR short boom main so I can carry a full main in quite strong wind. ....The headsail - now that is another issue!!!
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Old 26-05-2009, 20:33   #23
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The reef line (led to the cockpit) pulls it down. Slack the Halyard to the mark for the first reef and engage the clutch, put the reef line around the cabin top winch and crank er down. pulls the tack and the clew at the same time. Since the halyard is marked I don't even need to retension the halyard after the reef is in.
That is the way it is for me as well on a jiffy reefing single line system. I have two reefs set up. The third takes a 100% manual setting. Just one of those times when if it it is really going bad you need it done very early. Nothing really is that reliable in very heavy conditions. There still is a lot of stress until you get the reef in place. I know at 40 knots the conditions even when not stormy are difficult to mess with on the deck. When reefing after the conditions warrant the action it really means you screwed up. Too many things can fail at that point. The process of setting a reef exposes potential problems you avoid if you did it earlier.

A slack halyard while pulling in the reef is not a desirable situation. The sail is not under control and pulling out the slack requires extra stress placed on the sail for the whole operation. You are at a disadvantage should anything slow you down. In lighter conditions going forward would not have been risky but would have been more prudent. For the most part, you set the reef well before you have to so led back or not it's the same decision. If not leading lines back made you reef earlier, then it seems it would be the better situation. In those terms, the decision to reef is still the same no matter how the lines are rigged.
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Old 26-05-2009, 21:02   #24
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Any other folk have comments on Single line vs dual line reefing systems led back?
We have a Selden single-line reefing system set up. Used to have conventional jiffy reef with tack hooks at the mast. The single line reefing works great--shortening sail is a piece of cake. There is some friction, but not at all bothersome and easily outweighed by the convenience of pulling on a single line from the cockpit. Perhaps with a bigger mainsail it could be a problem.
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Old 26-05-2009, 21:54   #25
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Although I have not put it into practice, I have always believed that I can reduce the amount of friction in reefing lines led back to the cockpit by using smaller diameter rope.

I note that you can get Aramid fibre 5/16" (8mm) rope that has higher working load than 1/2" (12mm) double braid rope. You can get even thinner Aramid ropes with equivalent working loads.

Now, if you use the thin rope for the majority of the reefing line where it goes through all the high-angle blocks, but splice in a thicker tail for use in the cockpit rope clutch, I expect that you should reduce the overall friction (but maybe not by as much as I think, if anyone wishes to comment?).

It could also be that by choosing a rope with a low-friction cover (compared to the usual braid), or no cover at all, you may reduce the friction appreciably. Not sure you could then splice in a thicker rope tail for the clutch, though.

There could be other disadvantages to this approach that I don't see, but then, in a forum like this, I'm always hopeful that I'd be enlightened.

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Old 26-05-2009, 22:28   #26
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Maybe some kind of mast pulpit is all you need.
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Old 26-05-2009, 22:39   #27
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Unfortunately, I do have to go to the mast to put a second reef in, as the bottom 5 slugs are on a jackline, and the 2nd reef point will not reach the gooseneck, without taking out the bottom slugs, or untying the jackline, to allow enough slack so that the reef point will go low enough. I would like to change that somehow, if possible.
That is very easy to solve, you'll love this post ;-)

What you need is some webbing, waxed hand-sewing thread and needle, and stainless steel rings that do not fit through the grommets of your reef points in the luff. Put a ring on the end of a piece of webbing, wrapping the webbing through it and back on itself an inch and put some quick stitches in to hold it there. Put the other end of the webbing through the grommet, through a 2nd ring, back through the grommet, another loop through the first ring, back through the grommet and through the 2nd ring a 2nd time.

Now, adjust the length of the webbing loops so that when you pull one ring against the grommet, the other one can just reach the reef-hook on the boom without the need for taking sliders out of the track. Cut off excess webbing and hand-sew both ends. Done.

ciao!
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Old 26-05-2009, 22:49   #28
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What I miss in this thread is the cunningham. It seems that you all can tighten the luff enough with the halyard, I can't. I use the cunningham to tighten it by pulling down at the boom end.

My cunningham is very simple: a short piece of 10 mm spectra. I tie it to a reef hook, pull the other end through the cunningham grommet and on the other side directly to a mast winch. Now, for reefing, I do the same but use the reef point instead of the cunningham grommet. Yes, you have to be at the mast but I like that anyway, wouldn't want to reef from the cockpit. I want to check everything when we need to reef.

Also, about the reefing lines: replace double braid polyester with a thin (max. 10 mm) single braid spectra or vectran. A 10 mm single braid vectran has a breaking strength of about 22,000 pounds so you can go thinner if you want. The pro's are:

- this is slippery rope, reefing will be easier than ever.
- it doesn't knot-up/hockle or whatever you call that in English, while hoisting the sail.

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Old 27-05-2009, 01:06   #29
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My previous boat - a 25 footer used the cunningham - that seemed to work a treat. The purchase was about 3 to 1 then back to the cab top and I ran it all through a ring at the gooseneck to keep it controlled.
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Old 27-05-2009, 09:30   #30
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Nick - If I follow your advice, with the two stainless rings and webbing - Will this not leave the reef point 6" - 12" higher than it would be, if I were to take out the bottom slugs (or undo the jackline) so that the reef point is able to come down to the boom / gooseneck?
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