Spare halyard--what's the best line?

[Stumble]

I would point out that the use of the line as an external halyard doesn't really change the calculus much when dealing with dyneema. It is almost impervious to uv degradation, and chaff.

Personally I won't use Dacron for much of anything, since it stretches a ton, and has a poor lifespan due to uv damage, and age weakening. Plus it looses strength when wet... It just seems a poor material for use in marine environments. I would go with at least sta-set since it holds up better.

The other thing I didn't mention is expected lifespan. It has been years since I bought sta-set, but as I remember it gets really stiff and hard to manipulate after just a couple of seasons. My amsteel halyards are still supple and soft after 4 years in the sun (new Orleans area). I keep checking them for replacement, but I haven't seen any degradation that indicates replacement is imminent.

[JohnV]

It's very tempting, and undoubtedly would be a very satisfactory system. But to stay with your earlier points about cost/benefit, I'd be springing for 90-odd freet of Dyneema, in a size thick enough to grip, as a seldom-used spare, but using sta-set x with its relative stretch for the main halyard. I'd want to swap, and then I'd be back to having a fat, heavy dacron line as a spare, which I'm trying to avoid in the first place.
And 2 times 90 feet is costly and hard to justify on a heavy cruising boat. Especially when Mr. genoa halyard starts to get jealous.
And as I think about it, I'll still have the 3/8" spinnaker and staysail halyards, so maybe just a thin, cheap messenger is really the way to go.
Thanks for your ideas.
John

[allene]

Originally Posted by JohnV

It's very tempting, and undoubtedly would be a very satisfactory system. But to stay with your earlier points about cost/benefit, I'd be springing for 90-odd freet of Dyneema, in a size thick enough to grip, as a seldom-used spare, but using sta-set x with its relative stretch for the main halyard. I'd want to swap, and then I'd be back to having a fat, heavy dacron line as a spare, which I'm trying to avoid in the first place.
And 2 times 90 feet is costly and hard to justify on a heavy cruising boat. Especially when Mr. genoa halyard starts to get jealous.
And as I think about it, I'll still have the 3/8" spinnaker and staysail halyards, so maybe just a thin, cheap messenger is really the way to go.
Thanks for your ideas.
John

90 feet of 3/8 XLS = $77 => 4,400 pound strength, 3.2 inches stretch
50 feet of 3/16 Amsteel = $28
50 feet of 3/8 Tenex (use white) $20
Total $48 => 5,400 pounds strength, .82 inches stretch.

Splice http://L-36.com/halyard.php
Stretch calculator http://L-36.com/line_stretch.php

Enjoy.

Notes:
Size it so that you have a couple of turns of Amsteel on the winch with the splice below.

If you are concerned about the splice, do 90 feet of Amsteel and 50 feet of Tenex for less cost (slightly) than the XLS but much less stretch and much less weight aloft.

I did not figure out the splice before building my halyard using method 2. It works great. My next halyard will be method 1. The advantage of method 2 is that the line is about 7/16 but I find it a bit more than I need so next time I will just let the tenex be 3/8 without the Amsteel core.

But be sure to use white tenex because, like Amsteel, the colors come off on your hands.

Allen
L-36.com

[JohnV]

More good choices. This was supposed to be an easy decision...
Thanks for the ideas, Allen. I'll check out the references you gave me.
John

[Dan Lehman]

Originally Posted by Stumble

Personally I won't use Dacron for much of anything, since it stretches a ton, and has a poor lifespan due to uv damage, and age weakening. Plus it looses strength when wet... It just seems a poor material for use in marine environments. I would go with at least sta-set since it holds up better.

You must have mis-typed, and mean "nylon" vice "Dacron"
--for what you cite is true only of the former, not the latter.

As for the imperviousness of HMPE to UV degradation, I've read
conflicting accounts of that, including tests of quick-draws used
by rockclimbers left on climbs showing more strength loss than
similarly exposed nylon ones (!).

--dl*
====

[Stumble]

Originally Posted by Dan Lehman

You must have mis-typed, and mean "nylon" vice "Dacron"
--for what you cite is true only of the former, not the latter.

As for the imperviousness of HMPE to UV degradation, I've read
conflicting accounts of that, including tests of quick-draws used
by rockclimbers left on climbs showing more strength loss than
similarly exposed nylon ones (!).

--dl*
====

Dan,

Thanks for the correction.

You are right that some HMPE lines can't take any uv at all, but the new crop of dyneema lines can. It is a different material, and has different characteristics than some others. Vectran for instance has limited uv stability, PBO and Zylon as well have limited uv stability.

However dyneema, specifically amsteel and it's family of lines is highly uv stable, and suitable for uncovered use outdoors. Long term uv studies are still continuing, but the current recommended replacement interval for standing rigging made from dyneema is 6-8 year, as compared to 8 years for stainless steel rigging. My lifelines are going on four years, and still look new, I haven't destruction tested them, but they are still strong enough to break the welds on my bow and sterm pulpit before the line broke.

My halyards are also four years old, and I have yet to see any noticeable degradation on them, though I am thinking of switching out one of them and doing a destruction test just to see. Sadly I don't have a load cell or testing rig strong enough to really stress the line.