Spreaders when Switching to HM Rigging

[Essington]

Originally Posted by AnaLog

Hey Essington,
You don't give enough info about your boat or its intended use to go into any detail, but given its size and make one would guess you *really* don't need to bother with the danger, expense, or nuisance of dynema.

This is a small boat used primarily for day excursions. And it is true that I could just replace the gang with stainless just like it already has, but I am a rather long way away from the equipment used to make new rigging. This is a primary driver for converting to rigging that I can construct myself.

I'm not sure where you sail. But on my little lake, there is not a single documented knife fight amongst yachts, so I'll be lumping that danger right along with someone taking a cable cutter or hacksaw to the gang. Also since Dyneema does not stretch, it does not exhibit the violent behavior you encountered with your heavily loaded dock line.

Dyneema is stronger, lighter, stretches less, and does not work harden. I can construct the stays on site, and the asthetics match the boat. Nuisance and danger are not terms that describe Dyneema at all, and once the terminators are purchased, expense is pretty similar.

I am just left with how to best deal with the shrouds passing over the ends of the spreaders.

[Brion Toss]

Hello,
First, do not make your shrouds out of nylon.
Second, if you do, try to avoid touching them with a knife when they are heavily loaded.
Third, have you ever seen how steel wire behaves when it parts under load?
Fourth, Spectra stores less energy than either steel or nylon, and is in any event very hard to cut.
Fifth, don't touch it, or any other rigging with a knife, either. Loaded or unloaded, unless you want to cut it.
Sixth, correctly sized Spectra is several times stronger than steel for the same standing rig application, so even if you ignore the no-knife edict, you will be sawing a while.
Seventh, was there some other question? Oh yeah, spreaders. John Franta will be able to make specific recommendations, but I can tell you that it is much less of a problem than we had at first thought, precisely because the stuff is so very tough; a little radius is all you need. You might also try serving in the way of the spreader, or sliding a short piece of cover into place. This also works on lifeline stanchions.
Eighth and last, two caterpillars watch a butterfly going by. One says to the other, "You'll never get me up in one of those things."
Fair leads,
Brion Toss

[benz]

When I built my synthetic-rigged cutter, I used Delrin for the spreader ends. You can take a delrin sheave, saw it into four pie-pieces, them modify the pointy end to fit the spreader with a little imagination. I bored two small holes in the spreader end and lashed the spreader to the shroud with some HM line. It's worked perfectly for 5 years and 12,000 sea miles, and though I have spare spreader ends, I haven't had to use them--the first set is still good. I expect it won't be too long before people think of wire shrouds the way they did of Hemp shrouds 80 years ago--like a dinosaur well-laid to rest.
BTW, the Colligo fittings are top-notch.
Ben

[Essington]

I was thinking I'd need some custom milled delrin end caps, but the sheave idea is fantastic.