Want to Add Boom Vang to PY26

Scott T-Bird · Apr 15, 2012

That assembly won't work in my opinion.

Keep in mind that a soft vang isn't a very efficient way to apply downward force to the boom. First of all the downward force is applied to the inward section of the boom where you don't have the advantage of a lever arm that your mainsheet has, and besides, most of that force is applied inward towards the mast and not down as you want.

If you have a traveler, you can control twist far more effectively with the combined use of traveler and mainsheet, at least for the width of the traveler. I barely pay attention to the vang going upwind when the boom is inboard from the end of the traveler. But when you are sailing on a beam reach or further downwind, the vang is necessary to control twist.

Those pad eyes with two small screws are not going to do you any good. Those screws will easily pull out of your boom and your mast when you apply the forces necessary to affect twist of your main sail. My boat is very similar to yours, with only a slightly larger main sail. The standard set-up for my boat has saddle attachments at both the mast and the boom and there are at least 6 or 8 SS rivets that attach the saddles.

A 3:1 purchase won't do any good either. I have 4:1 on mine ... the lower set of blocks is a fiddle with becket and a cam cleat. The upper set is a fiddle block. I found that mine was also not useful when the control line is set with the cam cleat. The only thing it was good for was to guess at a twist setting and cleat it down BEFORE letting the mainsheet out for downwind sailing. Once the main was out, it was too late to try to affect any kind of adjustment. The control line would be bar tight and if it was uncleated, I couldn't gain any more and probably would lose what I had. Keep in mind that the friction losses are significant with the size blocks you are thinking about.

The only way I could really use the vang properly was to lead the control line back to the cockpit so that I could use the cabin-top winch. I recommend that if you want to utilize a vang, you should plan on using it with a winch (and get a 4:1 purchase minimum). You will also have to beef-up the attachments to boom and mast. You can use a thru-bolt (what's that called?

) on the boom, but I don't like to see those on a mast, except for the shroud tangs. I prefer the saddle attachments for this use.

Scott T-Bird · Apr 15, 2012

I'm like you in that I want to have all sail controls at my disposal. If I didn't already have a soft vang, I would consider adding a rigid vang. I think others have done that ... Joe on his Catalina 27, for instance? I've been critisized in the past for my arguments against placing so much reliance on a traveler, but a rigid vang that works effectively makes a traveler redundant, in my opinion. Read Rich's explanations regarding vang sheeting to understand my point. I caused quite a ruckas on this topic about a year ago. It seems that I don't have the credentials to discuss these points with authority so I was roundly criticized for my blasphemy. The irony is that with a soft vang, I have to utilize my traveler. But with a rigid vang, I think you can more effectively control twist at all points of sail and simply use the mainsheet to adjust angle of attack because the mainsheet would no longer be necessary for twist control. That makes the traveler redundant to some degree.

It sounds like you have a preference for using a vang to it's full advantage so why not consider a rigid vang? It's a budgetary matter, for sure, but it may be worthwhile.

Dave Groshong · Apr 15, 2012

3:1 is what I ran on my Catalina 22, worked fine. 4:1 is that much better. I like to use big boom bails to hang the blocks from, self tapping machine screws:

http://shop.sailboatowners.com/prod.php?14806

I've never had one pull out on my vang or mainsheet.

The mast hound works well too:

http://shop.sailboatowners.com/prod.php?14154

tomgrigsby · Apr 15, 2012

I'd say you will want a vang downwind regardless of soft or hard. The vang is the only way to keep the boom from lifting on a broad reach or run. No point in dumping air unless you're overcanvassed. I through-bolted my vang attachment point on the boom and at the mast. It won't pull out, and really isn't expensive. You can get some pretty good forces on the vang attachment points if you don't have it tight and the boom rises suddenly, so those are my recommendations - definitely add a vang, and throughbolt the attachment points. JMHO.

Joe · Apr 15, 2012

Squid.... no matter what you decide on, I encourage you to install the vang... you'll find many great uses for it. Many of the guys will recommend a bale type connection to the boom, mainly because it's hard to get backing plates behind the fasteners in the middle of the boom.... otherwise an eystrap would be fine. My rigind vang has a fitted boom bracket attached with threaded 1/4 hex bolts.

Like Scott.... I use the traveller more in upwind situations, but once the boom is outside the traveller track... the vang is almost mandatory. I have a garhaurer rigid vang... the purchase is like 16 or 20 to one... can't remember.... but I replaced a 4:1 soft vang. And if that wasn't enough I could use the cabin top winch to help. So... I recommend at least 4 to one for your 26 footer.... or you can take the 3:1 you already have and "cascade" it to double the purchase to 6:1. Take a look at some of the systems pictured in this link to get an idea. http://www.harken.com/rigtips/BoomVang.php

Finally..... 7/16 line is overkill..... If you're going 4:1... limit the line size to 5/16 or even 1/4 if you get a little stronger line. The reason is that the smaller diameter line will run more easily through the blocks... and the multiple purchase will reduce the line's load requirements.

Oops, forgot....... on the soft vang, 45deg is as far as I'd go.... any more will lose too much downforce.

Ron20324 · Apr 16, 2012

Squidd said:
Interesting that Harken shows pad eyes as attachment point even with the 8-16:1 advantage...I have Bails coming, I'm sure they'll be fine...

My B323 has eye-straps-type fittings with heavy-duty pop-rivets to the bottom track on the boom. I took off my rigid vang and went to 3/8 line. With a shackle on both ends of the vang, I can take the end off the mast and put it on the toe rail for downwind- or haul someone out of the water or raise the dingy or....

Scott T-Bird · Apr 16, 2012

Here are a couple of photos of my set-up ...

Our boats appear to be similar in hull form, displacement and sail plan except that mine has a slightly larger main than yours while head sail dimensions are very similar. Anyway, saddle attachments are original to the boat and as you can see, very beefy. I'd say that the angle of my vang is less than the 45d that Joe recommends. You gain leverage as the attachment point slides out towards the end of the boom but it takes greater tension on the control line (and greater pulling force against the attachments) to create the downward force since most of the force is pulling the boom against the mast. I couldn't tell you where the optimum point is as it is probably a calculus that I'm not very good at.

That force against the mast at the gooseneck may be a concern if you create that shallow angle and apply a lot of tension on the vang so I would take the mast cross-section into consideration. My mast and boom is pretty beefy for a boat this size, so perhaps the designer took that into consideration when positioning the saddle as far out as it is.

My control line is 3/8" but I should probably heed Joe's advise and change to a smaller diameter but high-tech line with very low stretch. Of all the control lines, I would hazard to guess that the vang may require the most tension, due to the inefficiency of the control angles.

Want to Add Boom Vang to PY26

Squidd

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Scott T-Bird

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Squidd

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Scott T-Bird

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Dave Groshong

SBO Staff

tomgrigsby

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Squidd

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Joe

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Squidd

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Ron20324

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Scott T-Bird

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Squidd

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