Dyneema as Furling Line ?

[PamlicoTraveler]

Is there any reason not use a Dyneema line for a furling line. The current 3/8 sta-set has chafed and I am thinking a strong fiber line would make sense. Any reason not to?

[casual]

Money for one,in 20 years I,replaced one furling line just for age.

[Jim Cate]

G'Day PT,

If you are talking about uncovered Dyneema, then consider that it is really slippery. This means that cleating or gripping in clutches is difficult, and if your boat is of a size where winching the furling line is required, then getting the line to grip on the winch can be an issue.

Otherwise, I can't see a problem. In fact, being to downsize the line a bit means less friction in fairleads and less buildup on the drum... both good things IMO. I know that on Insatiable II (with a fairly old Furlex as a genoa furler) even 10 mm line jams the drum too full at times, and being able to downsize to 8mm would be good.

Cheers,

Jim

[PamlicoTraveler]

Yeah, it would have to be a covered line so it could be winched if needed. Thanks

[S/V Alchemy]

I like (covered) Dyneema quite a bit in certain applications, even for cruising. Halyards come to mind. But furling isn't one of them, and given you need about a boat-length and a half, depending on your set-up, it's an expensive use of an unnecessary line, I feel.

Dyneema or Spectra line is great, for instance, as windvane control lines, specifically because of the low stretch. But to splice it appears to need executive-level patience as it's like braiding sardines.

[Nicholson58]

I seriously consider it. The non-stretch part would motivate me. I've not had to deal with it in a self-tailing winch so I'd have to ask the riggers at the yard. The line I use now, 7/16, is too small to work well in the self tailers for the running backs so I am probably sizing up. The mast is 80 ft and the 135% #1 jib requires power to furl and tack. We need to throw the line in the winch and add the Milwaukee power driver to bring the boat around. With just two of us, it has to work.

Let us know what you figure out.

[s/v Jedi]

The only problem with clutches and winches/selftailers is the smaller diameter of the line. You might need an extra wrap or two around the winch.

For a jib furler line, the standard "high tech" method is to remove the outer braid over the length where it doesn't get to the winch. Just cut the outer braid off and put a stitched whipping over the cut.

A second advantage is that the single braid core part will flatten on the furler drum, making for better operation.

On splicing double braid with dyneema core: you can just splice the core with a Brummel splice and then pull the cover over the splice and lock it with a whipping. The idea is that the outer cover isn't needed for the strength of the line.

ciao!
Nick.

[S/V Alchemy]

Originally Posted by Nicholson58

I seriously consider it. The non-stretch part would motivate me. I've not had to deal with it in a self-tailing winch so I'd have to ask the riggers at the yard. The line I use now, 7/16, is too small to work well in the self tailers for the running backs so I am probably sizing up. The mast is 80 ft and the 135% #1 jib requires power to furl and tack. We need to throw the line in the winch and add the Milwaukee power driver to bring the boat around. With just two of us, it has to work.

Let us know what you figure out.

A pair of Lewmar 65s and 1/2 inch will sort you out...if 1/2 inch will fit your drum.

[Weyalan]

Originally Posted by s/v Jedi

<snip>On splicing double braid with dyneema core: you can just splice the core with a Brummel splice and then pull the cover over the splice and lock it with a whipping. The idea is that the outer cover isn't needed for the strength of the line.<snip>

Splicing the core only, as described above is great in theory, but just bear in mind that the cover might not just be there for looks and handling, but might also be providing UV resistance. Sure some Dyneema based ropes claim UV resistance, but not all, and if they are double braid with a polyester cover, you might be better to go for the proper class 2 type splice (I used to find it devilishly hard, but having done quite few now, it isn't all that bad).

[kaimusailing]

I have 500 ft genoa on roller furler and I had a spool of 1/8" dyneema, so I used that for the furling line and it has worked better than I expected. It is slippery, so I don't have to use blocks to fairlead it. I use a 1 speed halyard winch on the mast to furl it and probably 10 wraps on that. It's no problem. I've got only one fairlead point at the staysail tack, so when I roll it up, I tie it off at the drum and make up the excess line there. It has held up well in the sun and will probably never have to be replaced (by me).

[s/v Jedi]

Originally Posted by Weyalan

Splicing the core only, as described above is great in theory, but just bear in mind that the cover might not just be there for looks and handling, but might also be providing UV resistance. Sure some Dyneema based ropes claim UV resistance, but not all, and if they are double braid with a polyester cover, you might be better to go for the proper class 2 type splice (I used to find it devilishly hard, but having done quite few now, it isn't all that bad).

I must have expressed myself poorly: UV protection is exactly the reason why core-to-core splices have to be buried inside the outer cover. The splice I described is fully protected by the cover, it's just that the cover itself isn't spliced because that doesn't add much strength.

cheers,
Nick.

[svTOTEM]

Single braid, 12 strand polyester line such as New England Ropes – Regatta Braid: no hackles, easy on the hands, easy on the wallet.

[tamicatana]

Maybe you might consider finding what the line has chafed upon, because Dyneema will chafe too, albeit it will take a longer time

[Doodles]

Originally Posted by tamif27

Maybe you might consider finding what the line has chafed upon, because Dyneema will chafe too, albeit it will take a longer time

Right, if its going to be covered Dyneema you need to figure out the source of the chafing. Since the Dyneema is the core its not going to solve the chafe problem ... at least not until the chafing gets that far.

[Valkyrie654]

I went to some 1/4" amsteel for our furling line seeing as how the furling drum did not have the room for the amount of line needed to furl the 155 genoa that is on it. There is no cover on the first 35 feet or so. The rest I covered with some 7/16" sta set cover. The hands, winches, and clutch never see the bare Amsteel. Now after 10 years it is still very servisable, with no need to replace any time soon.

If you are going to be using your furler to reef the sail, then low stretch is very important. When reefed, the furling line has a lot of load on it so it needs to be quite strong.

If your furling line is being chafed, find out what is causing it. The only long term solution is to treat the cause rather than the symptom.