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Main sheet traveller

Started by james3007, 03 Jul 2006, 02:29

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james3007

On my boat (3007), I have a mainsheet "horse" which is simply a piece of rope leading to aech side of the transom, with the lower mainsheet block tied to a fixed point in the centre of it. Is there any benefit to be had from leading each side to a cleat where they can be adjusted on the water? I have seen the centre mainsheet systems on the merlins where the traveller slides across the top of the hoop. I was told that it was done so that the main could be sheeted rigth in when sailing upwind without pulling the boom downwards as much, this makes sense but does it have a significant effect? Thanks is advance.

Antony (Guest)

The simple answer is that few people put the Merlin style square hoop in a 12 as there is a view that it seriously hampers the crew moving around the boat.

Most of us now use split end rear-sheeted mainsheets, so that the end that you probably have tied to the becket on the block instead splits and attaches to the transom at each side.  This goes some way to bringing the main into the centre without too much mainsheet tension, but not to the same extent as the Merlin solution.  Nobody has ever proven that being able to adjust the rear strops is worth the extra fiddling around every time you tack.

Antony

Tim L (Guest)

James,

there's a simpler way to get the same effect - get a mainsheet where the end splits into two thinner lines, tie these ends to the same two points on the outside of 3007's transom bar so that when the main is hoisted the apex of the two lines reaches the mainsheet block on the boom.  It has the same effect of reducing the downward pull on the leech in light airs when you centre the boom.  Sorry - not a very clear explanation - best talk to Tony Blackmore at Sailsport (Starcross) and he'll be able to male you one up.

So you back sailing 3007 for the summer holidays?

Tim
N3497

james3007

Hi Tim, yes I'm back for the summer, sailing 3007 and doing some crewing for Ian on his new Merlin. How are you? Thanks for the help, does the sheet then go straight to the helm? You say it helps in light winds, is the effect of the mainsheet tension small compared to the kicker in a blow?

Tim L (Guest)

Nice to hear that 3007s back on the water!

I'm presently creeping around in the fog somewhere off norway for work - looking forward to getting some sailing in when I'm back onshore, sailing a borrowed europe for a couple of events in scotland and then heading down for Burton Week.  Are you going to the championships - it's going to be  a great event and there's a fair bit of extra accomodation available if you're interested.

Split mainsheet goes from transom corners to block on boom (where it joins to the normal mainsheet) then back down to the ratchet block and to the helm - as per usual.

It's an advantage in light winds as with a non-split mainsheet to get the boom near the centreline you end up pulling a lot of tension on the leech of the sail which will then cause it to hook and stall.  With the  split system there's very little downward pressure on the leech.  You should set your leech tension by using the kicker (roughly - the back end of the batten should be parallel with the boom when hiked out sailing upwind - use less when reaching and running) in almost conditions.  Think Ian might have reduced the kicker purchase when he owned the boat so if you struggle to pull the kicker on in strong winds it might be useful to increase that (should be about 16:1).

Cheers

Tim

RogerBrisley

Hi Tim

Did you change the arrangement on your design 8 or did you leave the std SS strop? (I still sail with a Proctor C mast if that makes any diff to your answer.

Roger

3334

Tim L (Guest)

I think I left the top cascade as wire on the D8 but changed the others to string as they were a bit spiky for the crew!