Standing rigging DM20 vs SK78?

[odonnellryan]

Well it is a good point: I like my furler even though I only have a Yankee right now!

[Jim Cate]

Originally Posted by odonnellryan

Well it is a good point: I like my furler even though I only have a Yankee right now!

Nothing to stop you from using wire on the forestay and Dyneema everywhere else... lots of folks have done this and I've not heard any negative feedback from it.

Jim

[Benz]

Originally Posted by Jim Cate

Good grief, Ben, give it a rest. This has been an informative thread up till now, please do not sidetrack it with off topic personal opinions.

And, as far as I know, no one is recommending use of furlers on non-wire stays. However, if one used one of the furlers that incorporate a full length plastic bearing tube (or nearly such), perhaps it isn't such an outrageous idea. Dyneema is pretty chafe resistant stuff and it just might work. I'm not volunteering to be the alpha test case, though!

Jim

Sorry to offend: the nature of opinions is that they are personal.

But there is as yet no inexpensive and practical way to do a furler on Dyneema. I have seen very expensive carbon/kevlar forestays with heavy-duty swivels top and bottom, that furled with a zipper-luff jib and lashings top and bottom, but that's astronomically priced Gunboat stuff, very specialized. Anything, even a plastic tube rotating around a fixed Dyneema forestay, will chafe the dyneema---it's awesome, but can't compare to metal for abrasion resistance.
So, back to what I said before, shipping a furling sail with it's own torsion rope luff just aft of the forestay is the easiest way to deal. Some boats keep several of these, of different sizes, and just hoist the one they want while still rolled up, unfurl it, and away they go. It's better in the respect that you can get it down even if it jams mid-furl ( still the biggest danger of old-style furlers), and that your forestay is always visible to inspection and can't get carried away if the sail does (in other words, the forestay is dedicated to one job: supporting the mast).

I think (dear me, another opinion!) that with synthetic rigging, the old-style furlers that attach to a metal forestay are going to join the Dinosaurs in the "where are they now?" file.

[Jim Cate]

Ben, I've only heard of folks doing that for code zero type sails, not for jibs suitable for windward work. Seems pretty hard to get enough luff tension to keep from significant sag. But perhaps there are some developments that I am unaware of...

Jim

[Benz]

Originally Posted by Jim Cate

Ben, I've only heard of folks doing that for code zero type sails, not for jibs suitable for windward work. Seems pretty hard to get enough luff tension to keep from significant sag. But perhaps there are some developments that I am unaware of...

Jim

I've only seen it myself on pretty high-end yachts that can put serious luff tension on a MAX-core halyard with an electric or hydraulic winch, or have a halyard bullet aloft--again, serious $$$ involved. They also replace their halyards and jammer jaws quite frequently, giving us riggers some nice business.

I'm afraid I've seen no good way to put a coventional furler safely on a synthetic rope forestay, though. Best thing is to do as you suggested and keep the forestay metal. Or do as I suggest.....

[Snowpetrel]

Originally Posted by Benz

Sailmaker's thimbles take a lot of load to distort, but when they do, it's your first clue....kind of like a fuse. I doubt you'd put enough strain on 3/8" dyneema to distort one, though. Especially if you terminate with a lashing and the load is thus spread. I bent one with a hydraulic puller and a LOT of force. Alu rings take a far higher load to distort--haven't bent one yet, even at 8,000#

Easy enough to make and add a solid aluminium bushing inside a thimble to stop it distorting significantly under load.

Allmasts in Tasmania are doing some experiments with synthetic rigging underneath their normal reefing furler extrusions. Looks promising but they want to test them for a few years before they recommend it. And structural furlers like the colligo ones work well with synthetic rigging.