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  #1  
Old 11-12-2013
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Amsteel lifelines--why is a lashing needed?

a. To cut it away to get an MOB on deck.

If there are sufficient gates, this is not applicable.

b. To apply tension, understanding that we only mean to remove all slack; actual tension would bend the stanchions inward.

The pelican hooks remove some slack. The rest can be adjusted out by not using brommel splices at both ends. Instead, finish one end as a whoopee sling, pulling the slack out and whipping down the tail. In this way the lashing is eliminated and the line can be easily adjusted at any time. So long as the tail is whipped down, it cannot self-adjust and is just as strong as a splice (it is simply a bury splice with the tail exposed) so long as the bury is the correct length.

Seems cleaner, easier to fit and easier to service (either to adjust or un-splice, perhaps to re-fit chafing gear).
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Re: Amsteel lifelines--why is a lashing needed?

Lashings aren't required, but a whoopie splice isn't suitable. It is not as strong as a tapered bury splice or a double brummel, and can pull out in the right conditions. They are fine for some things, but not sutable for lifelines.

I favor lashings because they are easy and cheap, savings a lot of money on end fittings for very little trade off. But I know some who insist on gates, and there is a perfectly sutable gate plus eye that Johnson makes for about $100.
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Old 11-12-2013
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Re: Amsteel lifelines--why is a lashing needed?

If the lifelines are well oversized then breaking won't really be an issue. I agree with Stumble, the whoopie sling will break where the bury exits the core.
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Old 11-12-2013
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Re: Amsteel lifelines--why is a lashing needed?

Quote:
Originally Posted by pdqaltair View Post
a. To cut it away to get an MOB on deck.

If there are sufficient gates, this is not applicable.

b. To apply tension, understanding that we only mean to remove all slack; actual tension would bend the stanchions inward.

The pelican hooks remove some slack. The rest can be adjusted out by not using brommel splices at both ends. Instead, finish one end as a whoopee sling, pulling the slack out and whipping down the tail. In this way the lashing is eliminated and the line can be easily adjusted at any time. So long as the tail is whipped down, it cannot self-adjust and is just as strong as a splice (it is simply a bury splice with the tail exposed) so long as the bury is the correct length.

Seems cleaner, easier to fit and easier to service (either to adjust or un-splice, perhaps to re-fit chafing gear).
There are two other reasons not listed in your two:
1) You can use brummel splices everywhere. Without the lashing you can only use a brummel splice on one side, the other can just a stiched tail bury. It's a lot faster for me to do a brummel then a stitched tail bury.

2) Fit only needs to be close, not perfect. The lashing can be used for surplus.

I have 4 lifelines (2 per side) and did one of them without lashings. I did the other 3 with lashings to save time. With semi-accurate measuring I was able to do all of the splicing at home, then just lash and installed them on the boat.

My lashings (and most recommended) were doing with a dyneema core line, so I'm not sure that they are really that much easier to cut in an emergency.

Pelican hooks are expensive, so I don't have multiple sets of hooks.
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Re: Amsteel lifelines--why is a lashing needed?

Lashings removing slack is a good idea, at least for me. In addition to the points above: I'll be the first to admit I am not a splicing pro, but my lifelines (New England Ropes WR2) loosened a bit in the first month. My theory is the cover - although tight when milked on - was providing the initial tension on the line, instead of the core, As the cover eased out a little across the length, I got maybe 1/2" on a 15' span.

Last edited by paul323; 11-12-2013 at 06:40 PM. Reason: typos
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Re: Amsteel lifelines--why is a lashing needed?

Paul,

What you are dealing with is called constructional stretch, and is just the nature of any braided line. When they are put into service it takes a while for all the loose fibers to get pulled into line, and the manufacturing weave to tighten up a little. It has little to do with the nature of double braids, just line in general.

I am curious why you guys went with covered lines tho. There isn't a real need for it, and single braid is much cheaper.
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Re: Amsteel lifelines--why is a lashing needed?

Thanks Stumble.

I went with WR2 for a number of reasons:

1) Abrasion resistance
2) UV protection (I am in CA)
3) Appearance

And to some extend, I am a bit conservative so having a cover seemed like a good idea. I got a sample of the product, and was very impressed by the look and feel of it, and thought the higher cost was worth the perceived benefits. A professional installer would probably have more confidence in amsteel alone.
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Re: Amsteel lifelines--why is a lashing needed?

Good feedback.

a. Brommel splices can be tied without both ends available. The method is probably faster on a long line. Google it. Amsteel is child's play to splice.

b. Breaking. The weakens the line about 40% from the references I found; yup, that's serious. I would use 1/4" Amsteel for protection from UV and in any event line very rarely breaks around knots and splices, they more often break due to chafe, which will not be at the splice. The weakest spot might still be a stanchion pass-through or an attachment. This is something we allow for. But we we would need a special reason.

c. Pull-out. Not if the tail is whipped down and the bury is the same. Slightly longer bury is certainly practical. Any bury-only splice (Amsteel or polyester) can pull out if not lock stitched or whipped; that is the reason for the brommel lock; it does not add strength.

d. Gates are required if not all of the crew is athletic. I commonly take passengers over 80 and disabled. Correct, they are simple to insert where needed. In our case, we have 6 gates: fore and aft and one at each transom (cat).

e. Cover. My understanding is that over sized Amsteel will offer longer service life and better economy than the alternatives and I think I am not alone. Since the stanchion pass throughs are sized to pass 3/8" line, I will also add fiber chafe guards as needed, probably Spectra.

----

Yup, not a good idea. But there may be an application somewhere. That's why we ask around.
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Last edited by pdqaltair; 11-12-2013 at 09:48 PM.
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Re: Amsteel lifelines--why is a lashing needed?

Pdq,

Just a quick FYI. Dyneema and Spectra are the same thing. Spectra is just a trade name for sales in North America while Dyneema is used everywhere else. It's all made by the same company with the same formula.

Since dyneema is both the most abrasion resistant line, and the most UV stable, the best chaff guard for dyneema is actually just more dyneema. You can certainly add chaff guards to dyneema lifelines, but you are better off just using larger dyneema in the first place. It isn't much more expensive and it will be a lot stronger.

The best alternative to adding a brummel splice on either end for lifelines is just to do a tapered bury splice then lockstitch it. I actually use 50lbs test dyneema fishing line for the stitching thread, which makes it pretty much immune to UV, and is pretty easy to work with. It is a little slippery, so I do extra locks, but the principle is the same.
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Old 11-13-2013
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Re: Amsteel lifelines--why is a lashing needed?

Quote:
Originally Posted by pdqaltair View Post
Good feedback.

a. Brommel splices can be tied without both ends available. The method is probably faster on a long line. Google it. Amsteel is child's play to splice.
Not around an object (like the bail on a pulpit) that is being spliced into the line. That is why I said you can only do both ends if you use a lashing. One end goes around the pelican hook, the other end goes around the bail on the pulpit.

I've done both forms of the Brummel splice many times and do the "quick" version when I don't need to capture something in the splice.
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