Boom vang / strut question

ctva

ctva

Well-Known Member
Joined
8 Apr 2007
Messages
4,800
Visit site
I have finally got around to fitting a boom vang or strut to my SO34.2 and would be grateful of any advice or ideas. I've got the choice down to a spring loaded vang as gas seams too problematic in the long term and I like the simplicity, or a Barton strut with the glass rods. Any experience or opinions on the pros and cons for each would be gratefully received as I've not seen the Barton in real life.
 
Have fitted the Selden gas strut on numerous boats and have one my own boat.
My issue is the standard purchase is usually way too low to be very effective on a reach to a run when the mainsheet no longer exerts a much of a downward loading on the leech.
Fine if you remember to set it before you ease the sheet but a pain if you forget.
With many of the light displacement cruiser racers, actually having decent control of the vang can save a broach by dumping it before the rudder starts to cavitate in gusty conditions and then you'll wish you had a decent purchase to wind it back on again to eliminate the twist and stop the roll.

In my experience the gas strut ones seem to be pretty reliable although it is well worth washing these down with fresh water on a regular basis as all these type of vang tend to suffer from internal corrosion.

Another tip is to change the control line to dyneema as many of these vangs are supplied with stretchy braid on braid.
The larger vangs use a wire lead which is usually too long so we often shorten these to allow a cascade purchase.
You can significantly reduce the diameter of the line with the vangs supplied with Braid on braid as the dyneema swl is much higher and this then allows you to use smaller high load blocks which not only reduces friction but often these smaller high load blocks work out cheaper.
I use a cascade system on mine to give me 16:1 and its a joy to use compared to the original.
The standard line was 8mm but the 4mm dyneema I use has a higher swl.
 
Last edited:
Gas spring in a strut is the way to go. Don't use the rubbish plain steel spings that rust away, get a stainless one from a gas spring maker.
 
Good point.

Javelin said:
Have fitted the Selden gas strut on numerous boats and have one my own boat.
My issue is the standard purchase is usually way too low to be very effective on a reach to a run when the mainsheet no longer exerts a much of a downward loading on the leech.
Fine if you remember to set it before you ease the sheet but a pain if you forget.
With many of the light displacement cruiser racers, actually having decent control of the vang can save a broach by dumping it before the rudder starts to cavitate in gusty conditions and then you'll wish you had a decent purchase to wind it back on again to eliminate the twist and stop the roll.

In my experience the gas strut ones seem to be pretty reliable although it is well worth washing these down with fresh water on a regular basis as all these type of vang tend to suffer from internal corrosion.

Another tip is to change the control line to dyneema as many of these vangs are supplied with stretchy braid on braid.
The larger vangs use a wire lead which is usually too long so we often shorten these to allow a cascade purchase.
You can significantly reduce the diameter of the line with the vangs supplied with Braid on braid as the dyneema swl is much higher and this then allows you to use smaller high load blocks which not only reduces friction but often these smaller high load blocks work out cheaper.
I use a cascade system on mine to give me 16:1 and its a joy to use compared to the original.
The standard line was 8mm but the 4mm dyneema I use has a higher swl.
Click to expand...
Our Selden strut has a 12 to 1 purchase (hopefully see pic) and we could do with greater ratio to enable hand tightening rather than having to winch the last and most important few inches in. Do you arrange your cascade with more wire or Dyneema? I might try it myself. The main is over 30M2 and when club racing we really have to play it like a dinghy.
 
I have the Barton strut - twin fibreglass rods fitted to my 36ft S&S.
Works well - the only slight problem is that it occasionally pops out of the boom fitting - open-end alloy slots.
But other than that it is fine and supports the boom well for reefing etc..
I see no reason to change and I like the simplicity
When at anchor / on mooring I run the main halyard back to the end of the boom to take the load but suspect I don't really need to.
Martin
 
Many thanks for the comments above. Selden appears to be good but pricey, Allspars are quoting over £600 and I'm not sure if that includes the mast and boom tangs! Any thoughtas on the other makes like Sparcraft or Z Spars?

As an aside I phoned quite a few rigging suppliers yesterday and given the enthusiasm to provide information and prices (received a single scant email with an ex works, ex vat and ex delivery price), I'm amazed that they are still trading..... or maybe one small vang is not worth their time!!
 
The Powervang is the best. Some of the other makes are frankly very poorly designed, one common issue there being nowhere to run the required lines or attaching blocks. One of the things to watch out for is that the ends will fit the boom and mast fittings and/or it's possible to have fittings adapted or made, something is obviously always possible but you may be surprised how difficult it can be. When you fit it ensure that the strut can articulate over the full range with the boom both in and fully out.
 
Another vote for Barton Boomstrut, so simple I'm surprised no one has copied it. It works really well, is easy to fit, maintenance free and comparatively cheap. Only problem is very occasionally the top end drops out as mentioned before.
 
johnphilip said:
Our Selden strut has a 12 to 1 purchase (hopefully see pic) and we could do with greater ratio to enable hand tightening rather than having to winch the last and most important few inches in. Do you arrange your cascade with more wire or Dyneema? I might try it myself. The main is over 30M2 and when club racing we really have to play it like a dinghy.
Click to expand...

The cascade is dyneema with high load s/s blocks.
On mine I replaced the wire with dyneema and shortened it so that the first block just came out of the top of the strut when the boom was positioned as high as I would normally want it.
For example that would gain at least 24" based on your photo.
First line I used SK90 7mm which has a break of around 5 tons
Then I used 5mm sk90.
Each cascade part doubles the purchase with only the addition of one block.
Final part I use a covered dyneema so it can be handled and works in clutches.

I modified a Selden vang last month which was fitted to a Heok 52.
It's the biggest model they do and frankly was only good as a boom support as the purchase system was totally naff.
I made a stainless bracket that fitted over the main body of the vang and bolted right through.
I then mounted a spinlock clutch on the bracket and the first cascade line passed through the clutch on its way to a High load Harken turning block at the mast vang intersection and then up to the reefing winch.
So we wind on using the reefing winch, hit the clutch which frees off the winch.
In our sea trial it worked a treat.
Got photos at work, I'll see if I can remember to grab them.

The final
 
Barton boom strut is now my preferred - have tried the selden but love the simplicity of the barton along with the cost. Its the only none harken kit we bought for the boat.
 
Not liking Selden's price, I fitted a Z Spars one to a previous boat (First 29). This unit has a coil spring in it. Wasn't happy at all with it. The spring rate is too high and it's too bouncy, you want the much more constant characteristic and the damping of the gas spring. Could not recommend coil spring type.
Heard good reports of the Barton but not used one.
 
You must log in or register to reply here.

Share this page

Top