What's with the boom vang?

[Phil M]

Perhaps paying attention to sail shape is why I have absolutely no trouble tacking, regardless of wind conditions?

~Rich

The vang makes a notable difference in your sail shape? Do you also use a boomkicker?

Phil M

[Hamin' X]

Perhaps paying attention to sail shape is why I have absolutely no trouble tacking, regardless of wind conditions?

~Rich

The vang makes a notable difference in your sail shape? Do you also use a boomkicker?

Phil M

Yes.

~Rich

[Phil M]

Perhaps paying attention to sail shape is why I have absolutely no trouble tacking, regardless of wind conditions?

~Rich

The only time I ever have trouble tacking is in very light winds, although I can also backwind the genny on a tack. By NOT using a boom vang, the sail shape would be slightly baggier under light wind conditions, and be of more assistance than if the vang pulled the sail down tight. In which situation is the vang helpful for you?

Phil M

[Hamin' X]

In light air, I ease the boomvang, which allows the boom kicker to lift the boom and provide a fuller shape to the mainsail. This provides more power and actually increases weather helm a bit, which tends to force the bow across the wind. In heavier air, I tighten the vang, which flattens the main and reduces heel. I can tighten the backstay also, which bends the main part of the mast forward and flattens the main further.

There are many trick to shaping sail. On an M, which has a traveler, you could move the traveler to windward in light air. This will reduce the downward pull of the mainsheet for a given angle of the boom, allowing the boom to rise more and provide more shape. The converse is true in heavier air. Move the traveler to the lee to get the mainsheet more under the boom and flatten it. Some move the traveler in the opposite fashion, but on a Mac, I find that this over sheets the main and causes the boat to pinch, slowing it down and increasing heel, which increases weather helm.

On the foresail, you can use the jib/genny cars to the same effect, but it is sort of the reverse. More under the sail (forward), tends to bag the foresail and back is flatter. This is because you are using the angle of the forestay to pull against.

All of this is simplified, because it all involves sail twist, which is a real animal to discuss, but if you follow the simple principles and practice (called sailing and having fun), it will become second nature.

~Rich

[DaveB]

Rich,
I ordered a new 105 jib 2000 and a New Mainsail 2000 with two full battens and all I received was the new 105 jib.(3 years ago) I should have just ordered the standard stock 2000 main from Hansen but didn't relize it was a major job to order anything thru Hansen unless it was in stock.
The 2000 Main for the MacX looks to be a far improvement over the stock sail, the 105 Jib after 3 years is in excellent shape in hot SW Florida.
Hopefully Art will bring good news to our ears as I do need a new Main and Hanson sails can do it if they try.
Dave

In light air, I ease the boomvang, which allows the boom kicker to lift the boom and provide a fuller shape to the mainsail. This provides more power and actually increases weather helm a bit, which tends to force the bow across the wind. In heavier air, I tighten the vang, which flattens the main and reduces heel. I can tighten the backstay also, which bends the main part of the mast forward and flattens the main further.

There are many trick to shaping sail. On an M, which has a traveler, you could move the traveler to windward in light air. This will reduce the downward pull of the mainsheet for a given angle of the boom, allowing the boom to rise more and provide more shape. The converse is true in heavier air. Move the traveler to the lee to get the mainsheet more under the boom and flatten it. Some move the traveler in the opposite fashion, but on a Mac, I find that this over sheets the main and causes the boat to pinch, slowing it down and increasing heel, which increases weather helm.

On the foresail, you can use the jib/genny cars to the same effect, but it is sort of the reverse. More under the sail (forward), tends to bag the foresail and back is flatter. This is because you are using the angle of the forestay to pull against.

All of this is simplified, because it all involves sail twist, which is a real animal to discuss, but if you follow the simple principles and practice (called sailing and having fun), it will become second nature.

~Rich

[Phil M]

The converse is true in heavier air. Move the traveler to the lee to get the mainsheet more under the boom and flatten it. Some move the traveler in the opposite fashion, but on a Mac, I find that this over sheets the main and causes the boat to pinch, slowing it down and increasing heel, which increases weather helm.

~Rich

Perhaps it is pulling the mainsheet tight with the traveller under the main, that when tightening the vang, I noted very little, if any, effect on the shape of the mainsail. If I were racing another it might make a difference, because then I would want to win.

Phil M

[Catigale]

The best part of being a cruiser is you win the minute you untie that last dock line and cast off...

[mastreb]

In light air, I ease the boomvang, which allows the boom kicker to lift the boom and provide a fuller shape to the mainsail. This provides more power and actually increases weather helm a bit, which tends to force the bow across the wind.

~Rich

Aha! I do the same thing, which explains why I was getting unexpected weather helm after tacking in light air after I installed the boom kicker. I have to say that the boom kicker really seemed to help keep the mainsail powered.

Matt

[puggsy]

That boom vang is to prevent the boom kicking upwards, and altering the set of the mainsail...also it takes the strain off the mainsheet control...it should not prevent the swing of the boom from side to side...that is the job of a ' boom brake' if fitted.
hope this helps.

[Phil M]

That boom vang is to prevent the boom kicking upwards, and altering the set of the mainsail...also it takes the strain off the mainsheet control...it should not prevent the swing of the boom from side to side...that is the job of a ' boom brake' if fitted.
hope this helps.

I have heard that before. I just wonder how much strain the boom vang takes off the mainsheet control.

Phil M

[seahouse]

I just wonder how much strain the boom vang takes off the mainsheet control.

Can't be much- it's at a considerable mechanical disadvantage to the sheets. The strain relief function is very much secondary to its raison d'etre; to give control over sail twist and shape.

[Highlander]

Depending on your vang 2-1, 4-1, 6-1 ratio but their is a few on this site who have snapped their booms in half with a vang . I have a garhauer ridgid vang & I can put a bend in my boom very easily 'Beene" has a pernament bend in his boom already I beleive

J

[seahouse]

Hey Highlander!

Of course, I was referring to the mechanical advantage not within the vang itself (by virtue of the tackle arrangement) or the within the mainsheets, but by their attachment locations along the boom.

- B.

[u12fly]

Aha! I do the same thing, which explains why I was getting unexpected weather helm after tacking in light air after I installed the boom kicker. I have to say that the boom kicker really seemed to help keep the mainsail powered.

Matt

Matt and others... I have thought about installing a boom kicker, on my but BWY told me they affect the rotation of the mast. So I opted for the simple topping lift. I know that boom kicker makes a special vserion for the Do you have any issues?

Chris.

[mastreb]

Matt and others... I have thought about installing a boom kicker, on my but BWY told me they affect the rotation of the mast. So I opted for the simple topping lift. I know that boom kicker makes a special vserion for the Do you have any issues?

Chris.

Hi Chris, I installed the boomkicker last week, so I've sailed with it and without it. It certainly helps keep optimal sail shape in light air, but the primary reason I bought it actually had nothing to do with performance and everything to do with keeping the boom off the deck in port.

There is zero effect on mast rotation. BWY must be talking about the generic version or an earlier mounting method that bolted to the deck? The boomkicker (at least the one made for the Mac) bolts to the mast using a slug nut in the bolt rope track, not to the deck or mast foot. So of course it rotates with the mast and boom. My mast is rotating just as much as normal, although my mast has always rotated easily.

In all, the install was simple and I'm quite happy with it. I'm not a skilled enough sailor to provide a real analysis of it's performance merits however.

Matt