MERLIN ROCKET FORUM

Topic : Alternative Sheeting

The Rigging Guide now contains photos of the mainsheet arrangement favoured by the Leneys on Carbon Footprint. Steve and Gill might like to add a comment about some of the particular advantages/features of the system. Photos are courtesy of Tim Boswijk.

(Note to Self - get a life...I'm doing this at 2335hrs whilst watching Prog Rock documentary!)


Posted: 23/07/2010 23:38:41
By: Alistair
No don't get a life, who would post all these helpful photos for us!! We all apreciate your time Alistair.


Posted: 24/07/2010 09:27:13
By: Jez3645
I liked their sheeting system so much, I changed mine, with a few added modifications to make the boom come more easily to the centre line of the boat with a split tail mainsheet.
The zimmer I took out weighed hardly anything, so the advantage is more ease of movement about the boat.


Posted: 24/07/2010 18:45:11
By: Tim B
Hi Tim, I like the look of it as well, my crews always moan about having a centre mainsheet on their backs in light airs. What mods did you make to the arrangement to get good centrelining? Do you have to adjust it accomodate raking ? Got any pics you could forward ? Thanks in advance ATB Rick


Posted: 27/07/2010 11:07:28
By: Rick3432
Hello can I please ask:
1/ Why the blue bobble where the main splits and does this move?
2/ Is that a gybing strop with the handle?
3/ why the elastic connecting the split mainsheets?
thanks


Posted: 27/07/2010 11:46:35
By: dv
Neat.  The elastic connecting the ends of the split tail is a simple solution to a problem which plagued my experiments with this system, the sheet tail catching on the corner of the transom.


Posted: 27/07/2010 12:28:59
By: Andrew M
Thanks Alistair for doing that, and the other photos you've worked on.


Posted: 27/07/2010 14:15:46
By: Mags
Hi

Its the same system we have opn empty pockets. I can confirm the mainsheet does in fact catch around the transom,we came to the same solution, and less to do on each tack.


Posted: 28/07/2010 09:41:53
By: steve ward
I do like the idea of not having a traveller or hoop to worry about on every tack! It would also save me a fortune in traveller rope.


Posted: 28/07/2010 11:59:07
By: Jez3645
I have a modified version of this.  
My split tails run from the transom up through the aft boom mainsheet block, along the boom in a clear sailcloth tunnel on the boom, and then go into the larger diameter mainsheet via a nifty splice. So my system has the split tails running further along the sheeting system than Steve's (Carbon Footprint) . I have a slightly oversized mainsheet block on the back end of the boom to allow the nifty splice and split tails to run through easily.

The rest of the system is similar to Steve's..ie turning block is set slightly further forward on the boom (to enable the tiller extension to pass through in lighter winds when sitting far forward as possible), and I have a block on an adjustable strop off the boom (so to keep the mainsheet at a sensible length). However my ratchet block is mounted on the boom strop, not behind the jammer as per usual, I have 2 air blocks niftily-laced together to form a large mainsheet block and fid, which provide the degree of flexibility the blocks require from this sheeting system.

The elastic used to span the tails across the transom, run inside the tails up to the boom, so to keep the leeward split tails of the mainsheet (the non working one) taught to stop tangles/twisting and general misbehaviour around the aft quarter.

I used a hollow Maffioli 7mm mainsheet, which has a 5mm taper at the helm end to hang onto in "on the buoyancy bag" conditions. The split tails are made from 4mm spectra, worked up inside the mainsheet using a stainless fid. They turn around some vectran loops mounted on the outside edge of the gunwhales to an adjustable locking splice, so easily adjustable if necessary.

It's early days yet, but i"m loving the easy taking in light winds! I tried the system over the weekend in similar conditions to Shoreham (Progressively increasing wind to 18kts, big seas), with the 2 ratchets in the system, I didn't need to cleat the main at all, and as it got a little lighter I was able to turn a ratchet off.


Posted: 28/07/2010 14:55:30
By: TimB
I have tried 12 different systems of main sheet including split mains over the past 10 or 12 years and have com to the conclusion that if you set the strop height at the rear to a point with the masy upright ie maximum power conditions, the rest takes care oif itself. ie as you rake, you sail with the boom further to the quarter anyway and this works perfectly for me,  The ball on the top of the strop helps reduce yhe twist generated by the main sheet affecting the centering, Lengths of tiller extension, tiller and take off point on boom are all critical other wise you get in a right mess. Gybing handle is also very necessary.  
I love it, no over sheeting, no bits of string to break, no zimmer frame, simple and effective.


Posted: 08/08/2010 20:52:56
By: Steve
Looking at converting Business as Usual to split bridle (sorry Alex, just can't stop myself fiddling with the old girl!) - anyone know how much mainsheet to buy? Marlow gemini is £5.45 a metre, so it is an expensive thing to get wrong!!


Posted: 21/02/2012 20:45:18
By: Andy Hay
sheeting with a rear (split tailed) bridle would be made considerable easier if we were allowed to sheet directly from the boom similar to skiff sailors via a ratchet block (on the boom)- not allowed under the current class rules.  

Can anyone tell me why the rules are worded in this way? Maybe some scope for development?


Posted: 22/02/2012 11:50:42
By: Andrew Harris
I don't see anything in the rules about how the main (or any other sail) is sheeted?


Posted: 22/02/2012 15:03:43
By: Andrew M
I have just read the class rules following the link on this site and can find no mention of any sheeting arrangement regulations or restrictions which would prevent "off the boom sheeting". Am I missing something please?


Posted: 22/02/2012 15:06:03
By: Richard Saunderson
So have I and neither can I!
Andrew, which rule are you referring to?


Posted: 22/02/2012 17:45:55
By: Barry Dunning
Andy - will measure the old one in the boot of the car for you.

Mods I had to make included cutting a section of back of boom so that sheeting point stayed on centre line, (without the blocks "flopping over" if you see what I mean). This meant another hole in the middle of the boom as the mainsheet had to be fed inside.

Still have the modified boom and a very expensive mainsheet - offers?

n.b. did go back to a hoop but not because the system did not work


Posted: 22/02/2012 18:27:28
By: John
Save yourself some cash and use some 3mm dyneema for the bridle and stuff it up the inside of one of the hollow cored dyneema/poly mix mainsheets for a couple of feet, stitch at the ends, and in a couple of other spots, and whip the end of the mainsheet.


Posted: 22/02/2012 18:38:37
By: Dave
Hmmm I was lead to believe it was a rule, I'll have a look and get back to you...


Posted: 23/02/2012 09:55:20
By: Andrew Harris
You're right.... there is no mention of it.


Posted: 23/02/2012 10:11:06
By: Andrew Harris
where are the photos in the rigging guide?


Posted: 23/02/2012 11:43:50
By: Miles
I always though it was illegal to spray your hull / foils with the "super slippery" teflon/ptfe type sprays but have seen several people doing this. 
Anyone know ?


Posted: 23/02/2012 14:20:26
By: WP
IYRU - Rule 53

SKIN FRICTION
A boat shall not eject or release a substance, such as a polymer, or
have specially textured surfaces that could improve the character of
the flow of water inside the boundary layer.

This would imply that sprays that slowly wash away would be illegal ?

Any thoughts ?


Posted: 23/02/2012 14:28:02
By: WP
I do believe After Hours had a teflon coat on it's first sail at Salc.


Posted: 23/02/2012 19:26:13
By: broz
All very interesting, but how much mainsheet should I get?


Posted: 24/02/2012 09:44:14
By: Andy Hay - 3626 Business as Usual
Now builders have mended garage door, will measure in morning and get back to you


Posted: 24/02/2012 22:46:53
By: John
overall lengh including the strops 9m, strops 1.5m, so 7.5 plus 1.5m

That was an early version which was a copy of a fireball mainsheet, with longer strops, so you could get away with a bit less. Cannot find the final version.

There are two types of the Marlow Gemini. One has the 2 cores running side by side, the other has one core inside the other, cannot remember who makes it, I eventually used this one because it stays round better. Also it is easier to tapper the outer casing into the core, then do the split. This removes as far as possible any hard spots where the mainsheet turns the greatest angle on the end of the boom.


Posted: 25/02/2012 10:04:27
By: John
John, have emailed you - not sure if received?


Posted: 25/02/2012 16:39:58
By: Chris B (3062)

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