No, on many boats the mainsheet is cleated off on a cam cleat at the traveller block. The main reason it is led forward on your boat is so that it can be routed back to the cockpit more neatly.
Finally REALLY sailed my boat
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What I meant by that is I thought the main sheet had to go to the pivot point of the boom so that it acts like a hinge as the boom swings. If it is not run to this point(and then back to the coclpit or whereever) it acts as a brake holding the boom from moving on the traveller unless you realease the main sheet from the cleat.
Yes, that's correct. Having the main sheet go up to pivot at the mast is sometimes called a 'german' style mainsheet.
You can get the same effect by having the mainsheet com off the ends of the traveller.
Here are way too many options to look at:
http://www.harken.com/rigtips/mainsheet.php
For what its worth, here's yet another option which I first saw on a boat at my marina. Then also on a new Jeanneau (at least I think it was this brand from memory) at a Strictly Sail show. Instead of leading the sheet to a block at the gooseneck, then down to a deck block for routing back to to deck organizer and the cockpit, the mainsheet istead can be lead directly from the forward-most boom bail of the purchase system to a block at the base of the mast. The mainsheet will still hinge at the gooseneck pivot point. I was looking to improve my boat in the mainsheet configuration area which when I bought it had no boom vang and only a 4:1 purchase on the main sheet. The routing of the sheet that I observed on those other boats, I saw would better keep mainsheet clear of rubbing against the boom vang block and tackle. Far as I can tell, the arrangement is working for me. Best to show in pictures. The green line obviously is the mainsheet. My fiddle block at the traveller has been questionably modified by me to make it into a tripple. Not pretty, but its been doing the job.
While on the topic of mainsheet systems, has anybody at some point converted from standard (no bearings) blocks to low friction blocks (like $75 Garhaurer triple block that Joe has pictured in his post)? Is there a noticeable different in the effort needed to pull in the mainsheet by hand?
While on the topic of mainsheet systems, has anybody at some point converted from standard (no bearings) blocks to low friction blocks (like $75 Garhaurer triple block that Joe has pictured in his post)? Is there a noticeable different in the effort needed to pull in the mainsheet by hand?
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Both yours and Rardi's are similar setups. The error in your premise, though, is that you have not moved the pivot point to the boom, you've moved it to the deck(near the mast base). It should go to the gooseneck first, then down to the deck, then back to the winch/cleat.
In your set up, you can still move the traveller without uncleating the mainsheet as long as it is not fully tensioned because there will be enough slack in the system to compensate for the change. The downside is that moving the traveller will alter the mainsheet setting and affect the sail's trim (twist, mostly).
If you look in the Harken examples you'll note that none of them run the mainsheet diagonally from the boom to the mast base. Why?..... There is no "hinge" without a verical plane to turn on... thus you need to run the mainsheet along the boom to where it pivots, THEN vertically down to the deck to create a hinge. NOW you can move the boom from side to side without changing the mainsail trim.
Joe's analysis certainly has certainly got me thinking a bit harder than on most days. I need that to keep me young. I see the point, which I hadn't considered, that in the case where the mainsheet is led to a block at the base of the mast instead of a block at the gooseneck, if the traveler is shifted from dead center to either port or starboard, that will cause the mainsheet to tighten ... and hence will pull the boom tighter. This particularly if the sheet is already at high tension before the traveler is moved. On my boat, I would estimate the distance between the mainsheet forward bail and the block at the mast base is 7'. (I'm not at the boat so can't measure precisely.) The max amount that my traveler can move from dead center is about 2.5'. There are some other angles involved, but for the sake of simplicity, and assuming that the traveler is straight and not curved, using the pythagorean formula, at 2.5 ft off centerline, the length of the sheet between the same two blocks would become about 7' 5". (Square root of 7x7 + 2.5x2.5) Divide the extra 5" by the five up/downs of a 5:1 purchase would suggest that the boom would be pulled down an extra 1". I'll take another look at my setup to see if I can run the sheet through a block at the gooseneck, without the sheet scraping against the boom vang tackle. There must be a way? If not, I usually sail solo, and one needs to tack and/or adjust the mainsheet frequently on SF Bay. So I don't usually use the winch. Instead, when I want to sheet in tight, I luff into the wind then pull the 6:1 purchase by hand as hard as I can. The additional 1" of boom tension probably isn't critical for recreation sailing?
Anyway, please see the below photo of a late model Beneteau 37. It seems to show the mainsheet led from the forward boom bail to the mast base. Maybe they have some other adjustment to compensate that I'm not seeing?
Anyway, please see the below photo of a late model Beneteau 37. It seems to show the mainsheet led from the forward boom bail to the mast base. Maybe they have some other adjustment to compensate that I'm not seeing?
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I think the way I have it ran works fine. I don't see any thing wrong with the theory of it. The boom hinges at the mast and the sheet hinges at the mast and the sail hinges at the mast. They all hinge on the same axis.
Like Hermit says, if the sheet hinges at the mast, it does not matter if at deck level or at the gooseneck.
However, like rardiH36 says, if the traveller is straight then there will be some effect on sheet tension while playing the traveller. It is possible to have a curved traveller to counteract this effect.
However, like rardiH36 says, if the traveller is straight then there will be some effect on sheet tension while playing the traveller. It is possible to have a curved traveller to counteract this effect.
Let's stop the nonsense. Scott, please build a rigid wing sail and install the motors necessary to adjust it. You can make small incremental change to your boat for the rest of your life or you can just go for the gusto and make it into what you really want in one big leap. I'd suggest cutting off the keel, adding a couple of hydrofoils, add the rigid wing sail, a couple cross members and hulls and you will have a nice trimaran with outstanding performance.
That's cool, the important thing is you're out sailing your boat. I was just trying to illustrate the difference between your setup and the factory design.
Hermit:
Its been a good thread you started. Upshot from it is I think we can be satisfied with our mainsheet set-ups. When I was waiting yesterday for my boat to be hauled (past due for a bottom job and trying out a different propeller) I saw in person a 36ft Beneteau with the mainsheet led forward to the mast base from the boom bail. Just like the picture that I posted a couple of days ago. Joe has a point about the changing tension as the traveler is moved, but I'm thinking the effect must be slight for recreational sailing and if good enough for Beneteau, then fine for me and my 1980 Hunter.
I was intrigued with your arrangement of leading the sheet forward from the traveler block. That would be an easy modification on my boat. But I have an opening hatch on the deck just forward of the traveler, so the deck level lead would interfere.
Happy sailing.
Its been a good thread you started. Upshot from it is I think we can be satisfied with our mainsheet set-ups. When I was waiting yesterday for my boat to be hauled (past due for a bottom job and trying out a different propeller) I saw in person a 36ft Beneteau with the mainsheet led forward to the mast base from the boom bail. Just like the picture that I posted a couple of days ago. Joe has a point about the changing tension as the traveler is moved, but I'm thinking the effect must be slight for recreational sailing and if good enough for Beneteau, then fine for me and my 1980 Hunter.
I was intrigued with your arrangement of leading the sheet forward from the traveler block. That would be an easy modification on my boat. But I have an opening hatch on the deck just forward of the traveler, so the deck level lead would interfere.
Happy sailing.
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