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Discussion Starter · #1 · (Edited)
For better and worse my Contessa is basically stock all around - hank on jib, lines at the mast, no traveler.

While sailing upwind yesterday I was eying my main shape and lamenting the amount of twist. Without the traveler I had no real way to adjust it.

So I started messing around and what I ended up doing was rigging a large carabiner style fastener to cinch one half of the mainsheet down to the deck on the opposite side. This changes the geometry of the lines as they lead up to the boom end.

This is a good overview of my mainsheet and hardware:


And this is what I ended up doing:


First, on the left, is roughly the normal geometry when I'm sheeted in.

Second, on the right, is my new line in green with the black oval representing the carabiner style fastener looped around the mainsheet lines and cinched to an eye bolt on the deck.

The orange lines show the pull angle which can be thought of like a virtual traveler position. So the adjustment shown is like moving the traveler leeward, reducing twist.


Any thoughts on this idea? Better alternatices

The advantages are that it's simple, I can make up this line easily and stow it except when I want it. Unlike other things I mulled over (additional lines from the boom to the deck, two mainsheets) it still lets me adjust and dump the main from the usual place.

Of course the downsides are that it's an extra line that needs to be rigged, it needs to be completely swapped on a tack and it would increase friction on the whole system (which is already a problem).

Though I've seen plenty of Contessa's online with ugly homemade traveler contraptions and that's a direction I'm just not interested in going.
 

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Dinghies use a simple bridal arrangement that allows you to centerline the boom without a traveler. It won't allow you to bring the boom beyond center, but allows you to get to the centerline unlike your current system.

The 3rd option here is an example of it:
Mainsheet Systems - Craig's Website at Backfire.ca

I can't find a better image of one in use then this photo from our 505:


The only leg of the bridal that is doing anything is the windward leg, it is like having the mainsheet attached to the windward corner of the transom. As the mainsheet is trimmed the boom eventually gets to the centerline and both legs of the mainsheet bridal are now holding the boom centered.

I've never tried this on a keelboat. It should work, though the boom on a keelboat is usually shorter and the bridal may sweep more of the cockpit and get in the way.
 

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What is the geometry of your transom? Can you simply install a traveler track on it?
 

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Discussion Starter · #4 ·
What is the geometry of your transom? Can you simply install a traveler track on it?
No, the problem is the transom hung rudder. So the tiller swings over the entire transom.

Here is an example of a custom traveler solution. This one is pretty decent, but I'm not willing to do this yet.
 

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If you look at a Niagara 35 you will see that they use two main sheets, one on each side of the companionway. The effect is similar to what you are talking about with the advantage being that it is much further forward so the second main sheet has a greater effect. I quite like this sort of system since it is very simple.
 

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Controlling twist has alot to do with how you use your vang. the vang can control alot of the twist, by pulling down on the boom and using the mainsheet at that point to control the poistion of the boom. You can also have 2 main sheets. one fastened to each quarter, then you can control boom position and the height of the boom ( thereby controlling twist). this also works as a preventer to control crash jibes. All you need is another cam cleat and an eye. you already have the rest of the hardware needed.
 

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I agree with the above regarding the vang. Once the boom is out to the rail a traveler is ineffective - the vang is always effective regardless of boom position.
 

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My Bristol came with no vang or traveller. I added the Garhauer solid vang, which has lots of purchase, I think 12:1. I brought the line back to the cockpit. This is now my primary control over twist, and it works great. I also did away with the topping lift.
 

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Discussion Starter · #10 ·
My Bristol came with no vang or traveller. I added the Garhauer solid vang, which has lots of purchase, I think 12:1. I brought the line back to the cockpit. This is now my primary control over twist, and it works great. I also did away with the topping lift.
Right I had sort of been forgetting about the vang in this context. One reason being that it's at the mast, but the other reason is that it doesn't have a lot of mechanical advantage in terms of holding down the end of the boom. At least mine doesn't.

So I'll give the vang a try next time and see if it can get the sail shape I'm looking for upwind, but I suspect it will have trouble unless I cinch it down beyond the point I'm comfortable with.

Two Mainsheets:
A couple people suggested this but that's more complexity than I'd like. With end of boom sheeting my 4:1 mainsheet is pretty long (~60') and I'd rather not have all that extra line in the cockpit. Plus it's two things that need to be manipulated on tacks and jibes.

Alex W:
Alex I'm not sure I followed the description of the bridle arrangement you were talking about. Are there any other pictures? And the link you provided didn't worko for me.
 

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Right I had sort of been forgetting about the vang in this context. One reason being that it's at the mast, but the other reason is that it doesn't have a lot of mechanical advantage in terms of holding down the end of the boom. At least mine doesn't.
A basic vang should be 4:1. You can add a single block to cascade this to 8:1, which should be plenty of purchase on a boat your size. My 4:1 vang leads back to a cabintop clutch and winch, so I can get plenty of purchase on it that way.

One thing to watch out for with a high purchase vang is that it is usually attached to a single point on the boom and can apply a very high load to that point. It isn't unheard of to bend booms by applying too high vang pressure. On a sail with a bolt rope in the boom (instead of loose footed) this may also flatten the sail.

Alex I'm not sure I followed the description of the bridle arrangement you were talking about. Are there any other pictures? And the link you provided didn't worko for me.
Sorry that the link didn't work, it doesn't work for me now either.

This is a clear photo of a poorly executed bridal:


The bridal should join together into a single main sheet when the boom is sheeted in hard. On this one the bridal legs are a little short and it joins early.

When you sheet in the main hard the boom is pulled all the way to center and both legs of the bridal are under load. When you ease it a little bit the windward leg carries all of the load and the leeward leg of the bridal will be slack. You can see this in the photo that I posted from my 505. The boat is on starboard tack and the starboard leg of the bridal is under load, while the port leg is slack. The vang is used for controlling twist, the mainsheet is only used to control lateral position of the boom. Our 505 used to have a traveler, but this vang + mainsheet system works better and is simpler.

This system allows you to bring the boom to center better than your existing bridal system, which requires infinite load on the mainsheet to really center the boom.
 

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I've heard it suggested that you should make the boom vang line long enough to reach the wheel, and have a cam cleat for it. This way you can easily make changes to twist, and also depower the main quickly in a gust.

I've heard the bending the boom argument before, but I have my doubts for the following reason : applying the boom vang takes pressure off the main sheet, so you have spread the load between two points, the main sheet and the vang, reducing, not increasing, the bending moment on the boom.
 

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Discussion Starter · #13 ·
A basic vang should be 4:1. You can add a single block to cascade this to 8:1, which should be plenty of purchase on a boat your size. My 4:1 vang leads back to a cabintop clutch and winch, so I can get plenty of purchase on it that way.

One thing to watch out for with a high purchase vang is that it is usually attached to a single point on the boom and can apply a very high load to that point. It isn't unheard of to bend booms by applying too high vang pressure. On a sail with a bolt rope in the boom (instead of loose footed) this may also flatten the sail.
Right so it was the possibility of bending the boom, or more likely, popping the vang hardware out of the boom/mast (I've done this once) that concerns me. The vang is mounted at roughly the 1/4 point of the boom, meaning that there is 4:1 advantage for any force opposing it at the end of the boom. Plus the vang pulls at an angle, disadvantaging it further.

The vang hardware itself is 4:1, but a taught mainsail in a stiff breeze presents significant force opposing the vang. Tightening the vang is obviously a good suggestion for tensioning the main generally, but I don't think it's going to be the whole answer for me, at least with the geometry and hardware on my boat.

Sorry that the link didn't work, it doesn't work for me now either.

This is a clear photo of a poorly executed bridal:


The bridal should join together into a single main sheet when the boom is sheeted in hard. On this one the bridal legs are a little short and it joins early.

When you sheet in the main hard the boom is pulled all the way to center and both legs of the bridal are under load. When you ease it a little bit the windward leg carries all of the load and the leeward leg of the bridal will be slack. You can see this in the photo that I posted from my 505. The boat is on starboard tack and the starboard leg of the bridal is under load, while the port leg is slack. The vang is used for controlling twist, the mainsheet is only used to control lateral position of the boom. Our 505 used to have a traveler, but this vang + mainsheet system works better and is simpler.

This system allows you to bring the boom to center better than your existing bridal system, which requires infinite load on the mainsheet to really center the boom.
Ah yeah I see where you're going here and had some thoughts along these lines.

Is the bridle line (white in the picture) completely fastened to the purple sheet, or does the purple slide along the bridle? I think from what you're describing it's fastened right?

So this primarily lets you sheet the main in further while using the vang for twist.

It's interesting because allowing it to slide, by fastening the main to the bridle with a block for example, offers a different behavior where the block should slide leeward which would be equivalent to moving the traveler leeward (and should reduce twist).

I think this behavior could be increased or decreased by pulling in or letting out the bridle, offering something of the control of a traveler.

A theoretical next step would be to control the position of this block on the bridle directly with some additional lines which would effectively implement traveler functionality, except with the bridle line serving like the track.
 

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Look at the race boats at your marina, it won't take long to find one that has a permanent bend in the boom at the vang. There are at least 3 or 4 examples on my dock. The permanent bend usually takes place during a jibe where the vang was on tight and there is temporarily no load on the main sheet.

I know that I can apply enough vang pressure on my boat to temporarily bend the boom at the vang mounting point. It's easy to demonstrate, but I don't have any photos.
 

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Is the bridle line (white in the picture) completely fastened to the purple sheet, or does the purple slide along the bridle? I think from what you're describing it's fastened right?
Yes, it is tightly fastened. Some dinghies would allow it to move along the bridle, but then you can't bring the boom to the centerline. That would also not allow the leeward leg to go slack.

I made the bridal on our 505 basically by making a big eyesplice in the end of the mainsheet, then cutting it at the far end of the eye to get two legs.

So this primarily lets you sheet the main in further while using the vang for twist.
Exactly. Modern race dinghies are equipped with very high purchase vangs (16:1 is common, 32:1 is not unheard of).

It's interesting because allowing it to slide, by fastening the main to the bridle with a block for example, offers a different behavior where the block should slide leeward which would be equivalent to moving the traveler leeward (and should reduce twist).
Yes, but that only lets the main "travel down", and doesn't give you good control over that. The fixed bridal allows you to bring the boom to center, which can be necessary for good pointing (especially if there is a lot of main twist because you are spilling wind higher on the sail).

A theoretical next step would be to control the position of this block on the bridle directly with some additional lines which would effectively implement traveler functionality, except with the bridle line serving like the track.
Then you might as well build a traveler, you aren't gaining anything except for slop by having a soft traveler.
 

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The Capri 14.2 has a bridle and a barney post configuration... however, one of the "upgrades" was tie a bowline into the bridle dead center, so that sheeting from the barney post brought the boom to centerline. The downside of this of course was the boom was also pulled down.
Barney post and Bridle:
 

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I would try a rope bridle on the transom, with a free floating block, before making any bigger changes or purchases. This is what I have been using on some dinghies. May not be the best solution but it is simple, cheap, and works well most of the time. Just make it plenty strong so there are no surprises when wind pipes up.
 

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The Capri 14.2 has a bridle and a barney post configuration... however, one of the "upgrades" was tie a bowline into the bridle dead center, so that sheeting from the barney post brought the boom to centerline. The downside of this of course was the boom was also pulled down.
With the right bridal length the boom isn't pulled down so hard to center. On the 505s the legs of the bridal are often dyneema that is spliced in a whoopie-sling way so that the leg length can be precisely adjusted.

If you make the legs too long then you pull both legs into the aft boom block, which will pull it apart. If you make them too short then you have to pull the boom down very hard to center the boom.

A sliding bridal (as shown on that Capri or described by krisskross) is a very different setup with limited lateral control on the boom.
 

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A sliding bridal (as shown on that Capri or described by krisskross) is a very different setup with limited lateral control on the boom.
...and it is essentially what the OP already has. The sliding bridle just lets you sheet to the leeward corner. The system that the OP has is what I have, too. Recently while motorsailing all day into a headwind, I tied the boom directly to the windward sheet block to help center the boom. Not a good solution, unless you are going to leave it that way for a while.
 

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Discussion Starter · #20 ·
...and it is essentially what the OP already has. The sliding bridle just lets you sheet to the leeward corner. The system that the OP has is what I have, too. Recently while motorsailing all day into a headwind, I tied the boom directly to the windward sheet block to help center the boom. Not a good solution, unless you are going to leave it that way for a while.
Well not quite. Our current setups are essentially always pulling to the exact center. It's equivalent to a traveler that's dead center. The sliding bridle slides...so it's pulling to different places depending on where it ends up. Typically it will slide leeward which is the equivalent to moving the traveler leeward.

It's similar in that it's uncontrolled (though I do think adjusting the bridle length would provide some control), but it would have a different result.
 
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