Sealing a de-cored furling line

dunedin said:
Surely the core of a modern rope is the bit that provides most of the strength. ...
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With yachting polyester or nylon double braid rope the core/cover balance is almost exactly 50/50. A stantard eye splice, with the cover going one way the cor the other, depends on this ratio.

High modulous ropes (Dyneema, Tywon etc) carry most of the strength in the core and are spliced differently.

You do not strip the cover of a Dyneema rope for this purpose; the Dyneema core is too slippery and can slide down into the coiled core on the drum, creating terrible jams. And there is simply no need; if the drum won't hold enough Dyneema line, it is probably the wrong sized furler. That said, if the strain is not great, it can work.
 
thinwater said:
No, no, no. It is worth reinforcing that this is dangerous advice for any splice. There will be wear and it will weaken the rope invisibly.

Taper, milk inside, and then as he said, lock stitch over a several inch length using either waxed sail makers twine or a strand of cover.
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I only agree if you seal and end up with the typical rubbish 'mushroom' with sharp edges ....

When I seal - I make sure the end is rolled before it cools - makes it slightly tapered and has no sharp edges / mushroom.
 
Post #21 is long overdue ....

I was wary of posting that if a furling line is too much for the drum then maybe the line is not correct size ... but of course if you have an oversize genny - then ????

My 609 drum gets full with my furling line - but only obvious if I do not furl controlled sheet as well. I like to furl with sheet keeping some tension and then furling line lays better.

Years ago - I never heard of removing core on a furling line ..... not knocking it ... just think its possibly an item of todays fix-its instead of curing the real problem ?
 
On a previous boat i had Hood Seafurl equipment. The rigging instructions included the removal of approximately 1/3 of the core from the furling line at its drum attachment end, leaving the other 2/3 for comfortable handling. This allowed the the furling line to lay flat on the drum, increasing the drum's capacity and also eliminated the risk of the turns capsizing and causing an overlock. There was no instruction to taper the core or tie it to the cover. Only to heat seal the coreless end of the cover. In thirteen years I never had a problem. Interestingly, when i started sailing my current boat (fitted with Profurl gear) last year I suffered an overlock event. Removing 1/3 of the core seems to have been an effective deterent. Much easier to furl too. Again, I did nothing other than remove 1/3 of the core and heat seal the cover at the drum end.
Mike
 
mikegunn said:
On a previous boat i had Hood Seafurl equipment. The rigging instructions included the removal of approximately 1/3 of the core from the furling line at its drum attachment end, leaving the other 2/3 for comfortable handling. This allowed the the furling line to lay flat on the drum, increasing the drum's capacity and also eliminated the risk of the turns capsizing and causing an overlock. There was no instruction to taper the core or tie it to the cover. Only to heat seal the coreless end of the cover. In thirteen years I never had a problem. Interestingly, when i started sailing my current boat (fitted with Profurl gear) last year I suffered an overlock event. Removing 1/3 of the core seems to have been an effective deterent. Much easier to furl too. Again, I did nothing other than remove 1/3 of the core and heat seal the cover at the drum end.
Mike
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That's interesting ...

Braid on Braid ?

My concern with braided line with core - is the core sliding inside ... but this would be a more serious matter with a non braid core - such as twisted laid strand core with braid outer.

With a removed core at drum end - then very good reason to taper the inner core .... to avoid the hard ridge.
 
Refueler said:
My concern with braided line with core - is the core sliding inside ... but this would be a more serious matter with a non braid core - such as twisted laid strand core with braid outer.
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I don't see how this matters, the core is only left in in this case to make the rope easier to handle, you shouldn't have the core-less part as far as the winch or the last block (depending on size) so you'd never have to handle the core-less bit.

The core can't slip much further back toward the cockpit as the rest of the core is in the way and it can't slip very far forward as it's attached to the cover at the cockpit end.

Similarly I'm not sure that stitching it is necessary, once the cover is under tension it'll tighten down onto the core and grip it anyway.

I'm thinking of trying this as my furler does get a bit full, and you're probably right that it's a bit small for the boat, but if this works it's a lot cheaper than a furler.
 
stu9000 said:
No issue with strength then?
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So I guess from what thinwater is saying in post #21 is no issue with strength IF using conventional braid on braid, AND the rope is sized so big that removing half the strength doesn’t matter.
BUT winching in a reefed Genoa with a big winch must make the furler rope one of the highest stressed ropes on board.

And if the braid on braid is so thick that it has enough strength with half removed ...... then perhaps better to start with slightly thinner rope in the first place.
Me I am sticking with the Lyros cruising dyneema of a manageable size which I fitted last year.
 
stu9000 said:
No issue with strength then?
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Good point of course, other people seem to think it's not a problem.
Jimmy Green's has 8mm Liros braid on braid having a Breaking Load of about 1.5 tonnes, half that would be 750KGs.

How strong does a furling line need to be?
 
JBJag27 said:
Good point of course, other people seem to think it's not a problem.
Jimmy Green's has 8mm Liros braid on braid having a Breaking Load of about 1.5 tonnes, half that would be 750KGs.

How strong does a furling line need to be?
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A lot of ropes on boats are sized for comfort during use and not by strength. If by strength a lot of haliards could possibly be 6mm on boats up to 30 foot.
 
Boathook said:
A lot of ropes on boats are sized for comfort during use and not by strength. If by strength a lot of haliards could possibly be 6mm on boats up to 30 foot.
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Well exactly, in this instance you want it thick enough to pull at one end and thin enough to furl at the other...
 
JBJag27 said:
Good point of course, other people seem to think it's not a problem.
Jimmy Green's has 8mm Liros braid on braid having a Breaking Load of about 1.5 tonnes, half that would be 750KGs.

How strong does a furling line need to be?
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Much of the logic (guesswork ;) ) in splicing a length of dyneema was that in a dark wild night if something went wrong up front unnoticed then the strength (3800Kg MBS) of the 5mm dyneema would allow the line to be chafed nearly all the way through but still be plenty strong enough, plus dyneema is pretty chafe resistant to start out with and less dynamic movement with the near zero stretch should help as well. Furling line parting in the middle of a dark wild dark night letting a full headsail out with no way to reef is a very scary thought....
 
GHA said:
Much of the logic (guesswork ;) ) in splicing a length of dyneema was that in a dark wild night if something went wrong up front unnoticed then the strength (3800Kg MBS) of the 5mm dyneema would allow the line to be chafed nearly all the way through but still be plenty strong enough, plus dyneema is pretty chafe resistant to start out with and less dynamic movement with the near zero stretch should help as well. Furling line parting in the middle of a dark wild dark night letting a full headsail out with no way to reef is a very scary thought....
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Leaving Bembridge .. Snapdragon 23 ..... outboard got swamped when stern dipped in a trough and then crest passed through ... wind was getting pretty strong - we were going for a quick dash before a storm front moved in .. to Langstone across the Solent ..

Unfurled part genny to get going ... forestay parted from the deck and genny fully unfurled and perpendicular from mast... we were bouncing on sands near the fort ...
I went forward and used the spinnaker halyard to try save mast as a forestay. My pal Harry used the furling line to heave that genny down to deck so we could get it stowed ... Harry to this day still has the marks across his palms where he heaved that sail down ...
I called CG advised them of our situation and unable to proceed - with the weather getting worse by the minute.
Lifeboat then appeared .. rocket line fired ... towing line made fast and we were dragged back into Bembridge.

Yes - I can quite honestly say that a fully unfurled genny that is flying free is a nightmare .....
 
I can say that a partly jammed furler is also a nightmare if the wind is up, probably the worst failure mode for a furler other than losing the forestay.
I do like the dyneema idea, but it sounds like it might be overkill, and my splicing is rubbish...
 
Refueler said:
I only agree if you seal and end up with the typical rubbish 'mushroom' with sharp edges ....

When I seal - I make sure the end is rolled before it cools - makes it slightly tapered and has no sharp edges / mushroom.
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You will not find a rope manufacturer that agrees with that practice. If I am wrong, please post the manufacturer link.

Removing the core for furling lines is common practice with many professional riggers. It gives you a comfortable tail size and sufficient strength. Hood suggests it. In fact, I have added covers when people used too-skinny line.

If you are winching hard enough to break the cover you are going to damamge the furler. If the force is that high there is a problem with your method or something is jamming. Try furling down wind, with the genoa behind the main. You should be able to hand furl in most conditions up to about 40'.
 
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