Mainsheet traveller?

wragges

wragges

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www.minstercomputers.com
Ok guys, be gentle on me. After 10 years, I have recently crossed-over from the dark-side to the raggies by buying a Westerly Seahawk 34....2 x 385hp to 1 x 29hp in just 3 weeks!

...anyways, I keep finding things on my floating clothes dryer that I don't really understand the point of...for example:-

What is the point of a mainsheet traveller?

I understand what the genoa travellers are for, any why. However, unlike the genoa sheets, the mainsheet is attached to the boom, not the sail...so what's the point exactly?
 
Welcome!

The mainsail has more controls that the headsail.
Not all boats have a mainsheet traveller.
Try this It's more than you asked though /forums/images/graemlins/smile.gif
Mind you, you don't have to be an expert trimmer to set sails and enjoy it.

Good luck and enjoy it /forums/images/graemlins/cool.gif
 
OK, as simply as I can: The purpose of the mainsheet traveller is to change the angle of the boom relative to the centre line of the boat, without allowing the boom to lift. If you eased the mainsheet without the downward pulling effect of the traveller the boom would tend to lift and the leech (the after-edge) of the sail would fall off to leeward. This effect is called twist and in most cases is something to be avoided. If you looked up the sail you would see a nicely set lower part of the sail but a loose upper part of the sail. The traveller allows you to set the boom out to leeward with much less twist. It is sometimes good to have twist, but you probably don't want to go there just yet. As a general rule, try to set up the main so that the topmost batten is parallel with the boom. That means playing the mainsheet tension against traveller position.
Slightly off subject, in my experience the most common sail setting error is overtightening the main - hauling the traveller up beyond the centre line and hauling in the mainsheet as tight as you can. When you are close hauled, let the main out until fully the first third of it is luffing (flapping a bit) and you will pick up speed - guaranteed.
By the way, I have just become a power boater (Grand Banks 32) after a lifetime of sailing.
Go to my website, click on cruising resources, averting your eyes from any products on sale lest I be banned for overt commercialism, and click on Sail Handling on Adriana for a simplistic view of sail handling systems.
 
That's really straightforward, about getting the top batten almost parallel with the boom, now I can't wait to get out and try it. Thanks. And, the bit about luffing the first third of the main when close hauled and then letting the boat settle into a beat sounds intreguing, thanks again, shall try.
 
Dont worry too much. Pin the traveller in the centre of the track until you learn a bit more about how a sailing boat works. Then you can start using it to optimise sail shape in the way outline by others.

Get a decent book if you learn easily from books but consider a sailing course. This aspect will be covered in the Yachtmaster practical course I think you will find.
 
Basically the boom needs to be controlled in 2 directions firstly from swung way out for running and pulled in close for beating. However as stated the boom also needs to be controlled in the up and down direction.
Some non racing or old boats have a single point main sheet attachment or even an uncontrolled horse across the stern to attach the main sheet (boat end.)
Some of these boats then rely on a boom vang (tackle from the mast to deck interface up to a point about 1/4 way out the boom. This tackle will pull the boom down without pulling it toward the centre of the boat. It works really well when the boom is swung right out to stop it rising. Often stopping an unexpected jibe) However this boom vang has limited power as often as much or more power is expended trying to force the boom into the mast crushing the gooseneck than pulling the boom down.
When the main sheet is in the middle then it exerts much more force pulling the boom down than towrd to centre of the boat which can be usefull to flatten the sail.
The traveller enables this main sheet force to be directed more downward than toward the boat centre line even when the boom is required to be partially swung out.
So especially when on a broad reach in strong winds you can pull the main down flat making it all work by letting the traveller off to leeward but with main sheet fairly tight. This means the angle off attack of the wind to the sail is not so much as to knock the boat over yet still provides good foreward drive.
it is a bit hard without diagrams but you can imagine wind arriving from abeam 90 degrees. If the sail is out at 45 degrees you get drive forward with some equal force knocking the boat over. If you ease the sail out you get more force forward but in effect less speed of thrust. (and less heeling)
If you tighten the sail toward no wind you get less power but more speed of thrust and of course more heeling. (and often a stalling of the air flow.
So In this case you ease the sail out until the sail luffs at the front. This indicates the speed of the force is not as much as the speed of the boat or the apparent wind has gone too far forward.( tending to turn the sail inside out) You pull the sail in tighter enough to give it shape which also indicates you are getting best force with sufficient thrust speed to provide additional forward drive to the boat with minimum heeling. (if that is a problem.)
As you can imagine sometimes you can squeeze a little more boat speed by tightening the sail more but it becomes a real compromise and you can overdo it especially in gentle winds.
So as already stated ease the sail out as far as possible but use that traveller to enble you to keep the sail flat and working top to bottom.
Good luck and congratulations on the wisdom to buy a real boat. olewill
 
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