Vang Sheeting

[MainlySteam]

Many modern performance cruising yachts from small to well over 100 foot range, including from the top designers and usually custom built or small production run boats, rely on vang sheeting (the vang maintains mainsail twist rather than the mainsheet working against the traveller even when close hauled) and have no traveller at all. While our own boat is by no means a performance cruiser it is set up with a long traveller plus it also has enough power in the vang and boom to vang sheet - we find that we almost always vang sheet instead of using the traveller. I think many ex dinghy sailors will realise how this works.

In another thread this concept caused some criticism as to its applicability to any keel yachts.

I would be interested in hearing any experiences and views people may have had sailing cruising boats set up for vang sheeting. Or, if you have experiences sailing a race boat where it has been extensively employed (then obviously usually with traveller adjustment as well).

Thanks in advance

John

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[Sunnyseeker]

I see the Kicker, mainsheet and traveller as three different adjustements..
The Kicker pulls the boom down tightening or loosening the leech, and adjusts the twist power, release kicker and the sail de powers from the top, reducing heeling leverage in gusts, when reaching it can prevent a broach if done quick enough, in old IOR boats we had a kicker dump valve (panic valve) on hydraulic kicker systems.
The main sheet allows you to adjust boom position/angle.
The traveller allows you to release the leech tension (kicker has to be eased for this) but to retain the boom on the centre line, in fractional rigs the top bit twisting off doesn't effect the slot of the jib as it is above it. Or to give quick power dumps and fine boom control.
When fully or slightly over powered rather than just easing the main sheet which destroys the slot effect and looses the whole main, the traveller is brought up to windward and then the mainsheet is eased until the boom is centred and kicker eased to allow the boom to lift. You loose the top part of the main, but retain a good slot and shape in the bottom.
I've never heard of vang/kicker sheeting?
Its all about the ammuomt of control you want in the power of the sail, if your not sailing near the limit of being over powered it becomes a bit irrelevant.
However........I could be completely wrong, wait till Ben gets back and ask him?
Neil

<hr width=100% size=1>Oh ye who have your eyeballs vexed and tired feast them upon the wideness of the sea

 

[MainlySteam]

No, I am aware of what all the controls do. What I am interested in is any experiences people may have had sailing cruising boats properly set up for vang sheeting. It is also used on race boats but because every little matter counts they obviously use the traveller as well.

If you do a Google on "vang sheeting" I am sure that you will find quite a lot on it - just tried and got pages of it. If you get to the North Sails site I seem to remember there was a little on that in a manual they produced for one keelboat class - sorry can't remember what. You will at least find plenty on the internet for the J boats, dinghies, etc by the look of what I see on Google.

Thanks

John

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[NigeCh]

A bit of semantics: Kicker & Vang

There is a difference between a 'Kicker' and a 'Vang.' Originally the term Vang applied to the Gaff Vang but sometime in the mid-to-late 19th C the Americans sailing Bermudan Rigs brought it down to the boom and placed it where it is now and called it a Boom Vang.

In the 1930's Uffa Fox [not knowing the above] invented an 'anti-boom-kicking-strap' to stop the boom from lifting when tacking and it was of fixed length. We have called it the 'Kicker' for yonks without realising that it was a fixed length boom vang.


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[extravert]

A different perspective which may be of interest...

Dragonfly trimarans, and a few others tris, have no kicking strap/vang at all. They have a long centre-boom traveller. This and the mainsheet provide all the twist control required. It is not possible to get the mainsail out more than 60 degrees from the centreline anyway, because of the backstays. This might sound limiting, but is not in reality, because tris are rarely sailed deeper than a beam reach.



<hr width=100% size=1>Summer is what you expect - rain is what you get.

 

[Inselaffe]

I have no traveller and so use the mainsheet to change sheeting angle and the vang to keep leech tension when I let off the main.
What do I do to give more twist whilst retaining a small main sheeting angle without a traveller or solid vang? Use the topping lift? (doesn't sound like a good idea if trying to spill off the leech in higher winds).



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[Oldhand]

A couple of years ago we changed from a quick cruising boat (I don't use the term "performance" as it has been reduced to meaning "better than very slow" by some production yacht builders) with an excellent traveller system to an average cruising boat with no traveller and vang control in the cockpit. I find little difficulty with the latter for controlling sale shape but perhaps rarely use it to "dump" compared with the traveller. This is probably more due to the traveller in the first boat being easy to get at and the vang on the current boat being a stretch to reach. As a result I now tend to dump with the sheet rather than the vang because of the control positioning relative to the helm. (I don't usually have crew keen enough to play the vang and it is usually quicker for the helmsperson to dump than ask SWMBO to do it). All in all I don't really miss not having a traveller, but for some reason the builders are now fitting a very short one which I doubt if anyone uses.

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[flaming]

Believe it or not I actually have very recent experience of this.

At Cowes this year the boat I was racing (a Sigma 38) had a very poor traveller arangement, actually scraping small metal chips onto the floor of the cockpit when moved, so we avoided moving it too much, and couldn't use it to dump. We had to use the sheet. We were also using the vang to control twist.
From a performance point of view this had a few disadvantages.

Firstly it took two people to trim the main, and as the kicker was lead forwards to the coachroof they had to do a lot of shouting.
Secondly, on the breezy days the main had to be dumped in the gusts, this had to be done with the main sheet. This meant the main trimmer had to occasionally pull in large amounts of sheet as quickly as he could. He ended up very sore!
The other dissadvantage was dumping the sheet, is that the loading on the kicker was really high, and obviously stretched a bit under these loads. So with the best will in the world the boom did rise slightly as the sheet was eased. A couple of cm of stretch at the kicker can translate into some pretty big lifts at the back of the boom, especially as the clutches were struggling to cope with the loading that we wanted on the kicker.

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[MainlySteam]

It would sound as if all your comment is related to a boat not set up for vang sheeting alone. You will see that I actually say that race boats will be properly fitted with travellers and so I would expect things to not be quite as one would like if the traveller was problematic.

However, race boats with travellers do vang sheet
to some extent and some to a great extent depending on the capability and nature of their rig.

In a cruising boat all the people you mention do not exist - and no one pays any constant attention to all the details you describe on a cruising boat unless just sailing around the bay (in which case the boat is not being used as a cruising boat), but certainly not when cruising.

So I do not see your point because you have not related an experience in a boat set up for vang sheeting but rather one where you were forced into it. I assume you are not criticising the concept from that experience.

John

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[Sunnyseeker]

Bending the mast to flatten the main and reduce power (Kicker/vang sheeting) will only be effective on a boat with a bendy mast, on carbon tapered rigs you can do this easily but a Sigma 38 has a very stiff rig, as do nearly all cruising boats. Fun to try maybe, but easier to change the mast?

<hr width=100% size=1>Oh ye who have your eyeballs vexed and tired feast them upon the wideness of the sea

 

[flaming]

I don't get it, you ask if any one has sailed a race boat using vang sheeting. I reply that I have and then you say that it's not relavent!

Plus I'm not totally sure about your comment about "not set up for vang sheeting alone." Pray tell me in what way a vang differs when attatched to a boat that has no traveller?

I'm well aware of what happens on a cruising boat, I've been cruising my entrie life, I only started racing a couple of years back. I know that no one will actually be trimming the main, but does that mean that the optimum traveller position is in the middle?

My point is really a very simple one. The use of a traveller on a boat, be it racing or cruising, will serve to reduce loading on the boat in comparison with the same amount of vang use.



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[flaming]

We weren't trying to bend the mast, we were trying to close the leech.

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[snowleopard]

a vang/kicker can be set up to provide all the required downforce on the boom so that the mainsheet controls only the horizontal movement of the boom. the loads on the vang become very high but it makes mainsheet loads very light and the sail is kept flat even when the sheet is eased.

i have a boom which is engineered to rotate in the horizontal plane so i can set up the main to keep the same shape regardless of how far it is let out (even beyond 90 degrees). the sail twist is controlled by the outhaul and the 2 part centre mainsheet easily controls a sail area of 500 sq ft. see photos of the rig <A target="_blank" HREF=http://www.freewingmasts.co.uk/>here</A>

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[extravert]

> a vang/kicker can be set up to provide all the required downforce on the boom
> so that the mainsheet controls only the horizontal movement of the boom

I don't agree with that, and neither do North Sails. That's a quick way to break your vang or bend your boom in a racing boat in fresh conditions.

The X99 tuning guide from North Sails explicitly says that the vang should always be left slack when beating. It is not up to the job of controlling mainsail twist upwind, because that's not what it is designed for.



<hr width=100% size=1>Summer is what you expect - rain is what you get.

 

[MainlySteam]

It certainly can on cruising vessels, especially performance ones. Out of interest I have been looking back through the designs of a number of superyachts and I have to say that I am surprised how many of them are travellerless and again, many have single part mainsheets (ie no purchase on them, are taken straight to the winch).

There is no quick way to break the vang or bend the boom if it is designed to operate this way. They will certainly fail if they are not designed for the loads in the first place. One cannot say that just because the load is high the method is no good - no load is too high as long as the components are designed for it. Just because it is not recommended for the X99 does not mean that it cannot be done with other boats or that the concept is faulty. From what you say the X99 is clearly just not set up for it in so far as its rig design is concerned for strength and/or configuration.

In the end there are many performance cruising boats and super yachts boats appearing, including by de Frers, Dubois, Elliot, etc, etc that do not have travellers at all. I suspect that they know what they are doing.

John


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[extravert]

> In the end there are many performance cruising boats and super yachts boats
> appearing, including by de Frers, Dubois, Elliot, etc, etc that do not have
> travellers at all. I suspect that they know what they are doing.

I suspect they do, but they are outside of the experience of the boats most of us here own and sail.


<hr width=100% size=1>Summer is what you expect - rain is what you get.

 

[flaming]

"In the end there are many performance cruising boats and super yachts boats appearing, including by de Frers, Dubois, Elliot, etc, etc that do not have travellers at all. I suspect that they know what they are doing."

They will also have very large fixed vangs. Not adjustable ones as fitted to most smaller boats. In this case the sheet is purely for altering the angle of attack of the sail, so unless you had a burning desire to centreline the boom then I would agree that a traveller was not necessary. However, when you adjust the vang to contol sail shape the mainsheet and traveller combination is simply better at that job upwind.


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[MainlySteam]

Then perhaps it is the few with the experience which should be sharing that without those with no experience of it claiming that it is not a good idea because their own boat cannot be sailed well or safely that way.

So far it seems that myself and one or two others have boats capable of being sailed this way, I would certainly be interested in the experiences of any others, few as they may indeed be.

John

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[MainlySteam]

Re: Vang Sheeting Asked Again

For the sake of clarity I repeat my question, are there any views from people who have sailed the boats that I describe in the first post. I would certainly value your experiences.

Those who are only interested in hypothesizing from a position of no experience at all with such vessels perhaps should go and start another thread.

Thanks in advance

John

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[flaming]

I don't understand. I gave you a perfectly good account of sailing a boat in this way. The boat was clearly capable of being sailed in this way, as we didn't break anything upwind in 30 knots.
I believe I stated the advantages and disadvantages quite clearly above.

I would humbly suggest that if you attempted to flatten your sail with the mainsheet and trim with the traveller you will get a better upwind shape.

We are currently switching boats, the boat we have just put up for sale had a small and not that useful track. So we had to sail the boat in the way you describe. We broke the vang twice trying to flatten the sail.

Our new boat has a very good track, the whole width of the cockpit. Even when cruising (which is mostly what we do) the traveller will be used to control the main upwind.

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