Better main halyard arrangement?

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On my boat (42') I have a big fully battened main in 7.5 oz cloth, and it's jolly hard work to hoist. This is exacerbated by a fairly poor lead angle between the jammer and the coach-roof winch which I suspct has high friction. The cars are good Harken ones with ball races so are not the culprit.

I am now sailing quite frequently with a friend who is in his mid 70s and he can't raise the sail, and neither can my most of my children, so I want to do something about it. I had thought of fitting a powered winch, but don't like the idea (nor expense; £1000+).

Last week I had a go on a fast racing catermaran which had a good idea I thought; it had the halyard fixed at the _top_ of the mast, down around a block at the head of the sail, and back up to the mastand, over a sheave, and down inside in the usual manner. This gives a 2:1 advantage just where it's most useful and halves the effective friction in the rest of the system. Clearly it doubles the length of rope one has to pull and coil away, but in principle one can use one with half the cross sectional area so the bulkiness should be unchanged.

So I am seriously considering changing over to this system:

A 40mm block with dymeema loop on the sail
http://www.force4.co.uk/6090/Harken--40mm-Carbo-Ti-Lite-Block.html

and 8mm cruising dyneema halyard
http://www.xwrigging-online.co.uk/acatalog/copy_of_English_Braids_8mm_Dyneemabraid.html

But before I buy 54m (!!) of the dynema what do others do and/or think?
 
If you can rig it in a neat way it sounds like an excellent idea. I have a similar purchase on my boat, and I don't need to use a winch at all (much smaller boat than yours though).

I can't give you any pointers with the rigging details - my mast is wooden with blocks shackled to a mast band :-)

Pete
 
Several thoughts.
It will make the sail easier to hoist, but as you say it will make the halyard longer. You only need a small portion of the halyard (less than one third) to be high-tech / low stretch, but in practice you will have to have the whole halyard in the same material.
You won't be able to hoist the sail as high, without modifications either at the top of the mast or at the headboard.
One advantage is that, in your current setup, every inch of stretch of the halyard corresponds to an inch of drop at the head. Under the proposed setup, each inch of stretch gives you only half an inch of drop.
The most important consideration, from my point of view, is to make sure that you are solving a problem, and not working around one. What I mean is that you should identify the source of friction in the system, and reduce it rather than fitting a more powerful solution that doesn't reduce any friction, but overcomes it.
It can be a pain to identify the source of a problem (might mean a trip up the mast to look at the top sheave), but is almost certainly worthwhile in the long run.
 
In the longer term I'm thinking of doing something similar on a 43' boat.

I've encountered a 2:1 halyard on racing boats and a 50-odd foot cruiser. It seems to work OK. Interestingly none of them had a block on the sail head, the halyard was free to run through the shackle attached to the head of the sail.

I'm not sure if the shackle was designed for this or just an ordinary shackle. Something I still need to look into.
 
dt4134 said:
In the longer term I'm thinking of doing something similar on a 43' boat.

I've encountered a 2:1 halyard on racing boats and a 50-odd foot cruiser. It seems to work OK. Interestingly none of them had a block on the sail head, the halyard was free to run through the shackle attached to the head of the sail.

I'm not sure if the shackle was designed for this or just an ordinary shackle. Something I still need to look into.
Click to expand...
I've seen it on a maxi, where the weight of the sail made it in important feature.
I don't think I would lead it through a plain shackle, but you might consider a low friction ring which has the advantage of having no moving parts, and might also, possibly, be mounted closer to the sail, thereby losing less distance on the hoist.
 
bbg said:
I've seen it on a maxi, where the weight of the sail made it in important feature.
I don't think I would lead it through a plain shackle, but you might consider a low friction ring which has the advantage of having no moving parts, and might also, possibly, be mounted closer to the sail, thereby losing less distance on the hoist.
Click to expand...

That would work. I'm pretty sure it was a special shackle that gave low friction. It certainly allowed the head to be hoisted as high as normal.
 
Have you tried using a dry lubricant, e.g. Mclube sailkote, on the mast track cars? It's fairly expensive but a lot cheaper than the extra blocks and longer halyard so worth a go before you fork out on the new halyard arrangement. I've used it for the fully battened mainsail on my 35 footer and it makes a significant difference. It also makes dropping the sail a lot easier.
 
I can recommend this kind of arrangement. A boat I used to sail regularly (72' ketch) had her main halyard changed from a single hayard with the gooseneck in a track with uphaul and downhaul to tension the luff, to a double ended halyard with a 3:1 purchase on one end. It meant that instead of needing 2 or preferably 3 fairly heavy bodies to set the main, it could be done single-handedly or easily by a couple of teenagers.

It also means you need fewer winches which is nearly always a good thing in my view.
 
I would reinforce the advice to tackle the friction issue and perhaps check that the halyard winch is adequately specified. In particular, replace the sheave at the mast top as soon as you can, as the bore is probably oval by now and use the lubricant on the track. 20m of rope is hard enough to stow and handle without doubling it. If the solution you propose was really necessary it would be much more commonplace.
 
I recall some problems on a boat with a fully battened main I delivered.

The issue was resolved by releasing the leech line before hoisting and dropping, so that the battens were relaxed and not forcing into the cars and turning them against the slot, thus increasing the friction.

Easing the topping lift might also help.
 
Don't think it's friction that's the fundamental problem

Thanks for the helpful replies, and the link to the Antal site.

I have lubricated the mast-head sheave just in case, but don't think I have particularly high friction in the system since the cars run sweetly and the main drops and reefs really easily, and raises without any discernable friction (provided I pull at the mast base - see later). It's just that the main is heavy: I can bearly lift it when dry and in its bag, and probably couldn't when wet and/or c/w battens and roller cars; when it's nearly fully hoisted I can suspend my weight fom the halyard! Nonetheless I will have to go aloft anyway so will re-lubricate and check for ovality of the main sheave bearing.

But it's not an old boat or rig, and it's no harder now than it was from new, so left just to me I can carry on as is without problem. However a 75 year old lacks the physical strength and bulk required, which is what's prompting a change: even were I to eliminate all friction I think I'd still need a power winch or a mechanical advantage of some sort.

Back to friction, the one ill-designed aspect that I can see is that there is an array of some half-dozen jammers, all parallel, in a block set fairly close to the winch on the coach roof. Thus only one jammer can have an ideal lead angle to the winch - and it's not the main halyard unfortunately. Repositioning the jammers would possibly be a good idea, but that's quite a business given how strongly they are (and have to be) bolted to the deck.

I think a new block will fit between the top sheave and the head of the sail: in a conventional set up this distance has to accomodate the shackle and a length of splice where the thickened rope wouldn't pass easily over the sheave, so there is about 20cm gap.

Suplementary questions: does anyone have experience of using a thinner, high tec, rope? If so, is 8mm about right to replace my current 12mm - how does one calculate? it's not a strength issue - and what should the sheave dia be? 40 and 57mm seem standard.diameters.
 
Warning of a slight hic-cup I have experienced, the 2:1 idea works well but make sure the block on the sail head cannot swivel and is put on straight. A 60'er had a 2:1 hallyard but the block was not attached to the sail straight as we were setting out, so the two legs of the hallyard had a half twist in, not a problem with the sail down but once the block was at the mast head and winched tight it jammed. We pulled in the cunningham and knew no better untill it came to drop the main which would not move. Guess who got the short straw in the middle of Dublin bay!

Stuart
 
"Back to friction, the one ill-designed aspect that I can see is that there is an array of some half-dozen jammers, all parallel, in a block set fairly close to the winch on the coach roof. Thus only one jammer can have an ideal lead angle to the winch - and it's not the main halyard unfortunately. Repositioning the jammers would possibly be a good idea, but that's quite a business given how strongly they are (and have to be) bolted to the deck."


you could set up a tweaker block, just to check that the lead angle is not a problem.
or temporarily feed the main halyard through the most central jammer just to see how that would work ?
 
Sounds like a possibility. Make sure that that block can't get fouled on anything up there. I have a dayboat with wire/block/rope halyards and the blocks are very fond of getting caught up on rigging items.
 
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