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  #1  
Old 01-22-2015, 07:49 AM
Essington Essington is offline
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Default Spreaders when Switching to HM Rigging

I am planning to replace most of the standing rigging on a 24' Columbia with line (probably STS-HSR).
Colligo makes fantastic terminators and such, and I am sure that they will point me in the right direction for the ends of my new rigging, however, I'm left with a big question ...

What do I do at the spreaders? Currently the shroud runs through a slot in the end of the round aluminum spreader, and is wired in place. But that technique wouldn't work with Dyneema. What is normally done at the spreader ends when changing a boat from wire to rope rigging? Are shaped delrin end plugs/caps a reasonable solution? Is the spreader end fixed or stoppered to the Dyneema rigging somehow? I'm curious what others have done, because I've not been able to find any info on this topic via google.

thanks.
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  #2  
Old 01-31-2015, 02:12 PM
AnaLog AnaLog is offline
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Hey Essington,

There's nothing like other people's problems, eh? So here's my two cents while I stew on my own problem/s.

A few years ago I had a dock line with a knot that WOULD NOT be undone. I had new dock lines, so for fun (it's all fun I decided to cut the old line while under tension and see if it was *really* like the danger everyone blathered about.

OMG!!!

A T-storm was blowing quite predictably violently, and I had a new dock line in place, and all I did was *touch* the old dock line with a sharp knife and THWACK - it friggin' parted like any bat out of hell fantasizes it could!

It parted so fast and easy with just the TOUCH of a sharp blade after that I decided I would NEVER have synthetic rigging on my boat. It was so impressive I am Still on the negative side of even carrying dynema as a spare shroud.

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.
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  #3  
Old 02-01-2015, 06:56 AM
Don Z. Don Z. is offline
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You haven't said what kind of rope you used to make your dock line. Because a dock line needs to stretch, I'm assuming it was something elastic. Dyneema is known for collapsing rather gently. Not sure this is an apples/apples comparison.
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  #4  
Old 02-02-2015, 10:47 AM
Essington Essington is offline
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Quote:
Originally Posted by AnaLog View Post
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.

Last edited by Essington : 02-02-2015 at 10:51 AM.
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  #5  
Old 02-06-2015, 02:14 AM
Brion Toss Brion Toss is offline
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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
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  #6  
Old 02-08-2015, 04:54 PM
benz benz is offline
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Default delrin

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
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  #7  
Old 02-10-2015, 04:24 PM
Essington Essington is offline
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I was thinking I'd need some custom milled delrin end caps, but the sheave idea is fantastic.
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