Do I need a vang if I have a traveler?

Don Guillette · Dec 7, 2014

Three things -- first, You can use the boom vang in a pinch as a preventer but obviously only if it's a soft vang. I think a better choice for a vang is a rigid vang and Garhauer is a good choice. It was the second best mod I made to my boat -- the best was an adjustable fairlead system if you have a masthead rig because the jib is the engine.

Second, as Stu J points out, there is not a cruising way and a racing way to adjust your sails -- there's only a right way and a wrong way.

Thirdly, here's why I don't think a mate will ever get to hull speed without a boom vang. As I mentioned, the boom vang is the primary sail trim control to adjust TWIST. You can use the mainsheet but it's a poor substitute and when you start adjusting with the mainsheet you're also messing with the angle of attack and draft position. How many times have you seen boats with the top 1/3 of the main (and the jib) twisted off? 50% of the boats on any given day sail that way -- check it out the next time you're on the water. What is happening is power is spilling off the top of the sail and only the bottom 2/3 are driving. Check out advertising boat pictures in any sail magazine and you'll see the same set up -- it looks photogenic but it not efficient.

This question really belongs on the SAIL TRIM FORUM but I'm glad Jackdaw, Stu J and the sail trim professor emeritus (I hope that's how you spell it) RichH showed up. These forums are generally OK for maintenance issue but some times misleading sail trim info is presented. On the sail trim forum, incorrect info doesn't last 2 seconds -- I know because sometimes over the years my fingers get ahead of my brain and I'm corrected very quickly. There's a whole bunch of guys over there that really know their onions about sail trim.

Umphrey1012: the bottom line is you have a nice boat and what's a few more bucks to sock into it. Buy a rigid vang, you won't be sorry. Tell your wife it only cost 50% of the actual price. That's what I tell my wife -- she knows I'm full of crap but lets me get away with it!!

Meriachee · Dec 7, 2014

But Don, the ability of a person's boat to go hull speed, tied to the dock, while sitting in a lawn chair admiring the ability of the boat to go hull speed is such a common argument, it would appear that there is no need for any appliances whatsoever, and usually comes off in much more of a closing statement manner, "well my boat goes hull speed, so nah nah..
As usual, your argument is a valid one, and I would wholeheartedly agree with one point in particular, the EZGlide cars are without question the single coolest upgrade on the planet. You can see an immediate impact in the sail shape, with a degree of control that would never have been known otherwise. We use it all the time, and the difference is amazing.

(hopefully that commentary won't incite. It's not intended to)

Cheers
Gary

Don Guillette · Dec 7, 2014

Meriachee: Absolutely, on the EZ glide!!

You wouldn't believe how many skippers have invited me on their boats to help them with sail trim. In many cases I see the problem instantly especially on masthead rigs -- the fairleads are frozen in place!! The next thing I check is the outhaul -- it's stuck. So, the settings for both sails are like the broken clock. They are right for one point of sail and wind condition and wrong for all others.

Before we leave the dock we have a discussion, using a small model sailboat, where I explain draft depth, draft position, twist and angle of attack and also explain how each sail trim control for the main and jib interact with each of those elements. Sounds like a lot to discuss but it only takes about 15 minutes because I've done it a million times. Once the skipper has a basic knowledge of what each sail trim control is doing the rest is easy.

Bill Roosa · Dec 7, 2014

Wither you will get your money out of a vang install depends on how much downwind sailing you do. If you don't sail in winds that are over twice your boat hull speed you are not going to be doing much downwind sailing due to that apparent wind coming forward thing. when the boat speed and true wind speed are near equal the odds of them blowing directly at your destination are pretty low. all other wind directions will be some sort of beating (where your vang is of little use)
FWIW

Stu Jackson · Dec 7, 2014

Bill Roosa said:
all other wind directions will be some sort of beating (where your vang is of little use)
FWIW

We use the vang on all points of sail, it is, as Don points out, a sail trim issue. Less use, perhaps, but not little use.

Sprega · Dec 8, 2014

On the wind, traveler adjusts angle of attack, main sheet adjusts twist. Off the wind, main sheet adjusts angle of attack, vang adjusts twist. Yes, a vang is a basic sail trim control. One advantage of having a vang that I haven't seen mentioned on this thread is when you use a vang on a run, it greatly reduces chafe on your main sail. An unvanged main on a run that is all the way out to the shrouds is busy destroying its self. Every time the boom lifts, the sail slides up and down the rigging and wrapping around the spreader tip. Add years to your sail life. Use a vang. Ditto on the threat of a jibe. If you accidentally jib with out a vang and the boom lifts, it could hit the back stay and take the mast down. I've seen it happen.

Sailor_Jeff · Dec 9, 2014

Stu Jackson said:
I agree about not needing a sailboat, but if you have one, why not sail it correctly?

g.

Stu, that's not nice. Why not simply say that you think your 1940's learned out if a book way is better? Instead of accusing us of not doing it correctly. We are not all "Missionary Position Sailors".

However, on the Hunter 27 you are probably correct. My boat is designed differently. So I really probably should not talk about the hunter.

Jackdaw · Dec 9, 2014

Stu Jackson said:
We use the vang on all points of sail, it is, as Don points out, a sail trim issue. Less use, perhaps, but not little use.

Upwind in most breezes we leave our vang off. We want the mainsheet trimmer to have full control over the shape and twist of the main, and when left on, the vang invariably was locked in a mid-range position that limits twist.

The exception is in a big breeze or puffs, when we we might need vang sheeting. The 36.7 has a 7 foot traveler, so we usually don't run out of that.

Sprega · Dec 9, 2014

Good point Jackdaw. When I moved the traveler on my boat from the cockpit to the cabin top, I made it as long as I could get away with. I once saw a large off shore racing catamaran that had a u shaped traveler the width of the boat. No need for a vang in that situation.

thinwater · Dec 9, 2014

Even multihulls, with very long travelers, can occasionally make good use of a vang, when the boom is eased way off... but we sometime do it a little differently.

I use and adjustable preventer. The ONLY time I need a vang is sailing wing-and-wing, or very deep in a blow. Up wind and reaching, the boom is well controlled by a wide traveler, but at some point the sheet is eased to get the boom further out. I clip on a preventer line (needed anyway when going very deep), which is routed through a block a the midships cleats and back to a winch, and add what ever tension is needed to get the boom down where I need it. Two birds with one stone.