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Old 27-05-2013, 15:36   #1
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In defence of the sheet bend

On another thread (entitled "Rolling Hitch on Snubber") it has been pointed out that a sheet bend has a couple of deficiencies which seem to disqualify it from serious consideration.

When used conventionally, it is not particularly secure, and weakens the rope more than other bends.

Other bends, notably the Zeppelin and the Alpine Butterfly (the latter has to be modified from a loop to a bend) do not share either of these problems,
and the latter has a form which is particularly easy to remember –

– but neither is as easy to tie as a sheetbend, which is arguably the easiest of all bends in this respect.

The sheet bend has two other attributes which (as far as I know) are unique, and make it (to my way of thinking) indispensable.

Firstly it can be tied when you have almost no protruding length.

Secondly it can be tied when you have no access to EITHER end of a loop of cordage.

This second attribute makes it a 'Go-to' knot when you have to bend a line onto a sling or loop. I don't know of any other reliable bend which is applicable like this.

This is the context where it came under discussion, and was – I think – unfairly dismissed, in a recent discussion on this forum about attaching snubbers to anchor chains using a sling.

The two deficiencies are neatly sidelined in this application: the security is no longer problematic when BOTH ends of the standing part share the tension on that side of the knot, and likewise the sharing of the load throughout the bend means that localised load concentration, weakening the rope, is no longer a serious issue.

The left thumbnail shows a bowline;

the middle shows a sheetbend used to tie to a sling or loop (showing it is structurally identical to a bowline, although the load distribution is different);

and the right picture shows the conventional sheetbend (whose load distribution is different again, and inferior to both the other knots)
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Old 27-05-2013, 15:52   #2
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Re: In defence of the sheet bend

I know of at least one other cool way to attach to a loop or sling: the lark's head toggle

aka cow hitch toggle

Once again, it has the special advantage of being applicable where you don't have access to either end of the item you're trying to secure.

It's also particularly useful for joining wire hawsers or ultra-large rope hawsers end to end, in cases where they have a spliced eye.
(There is a simpler but less convenient way, same idea but without the toggle, but I don't know what it's called or how to explain it. Might have to wait until I can contrive a diagram - maybe someone else who's a mind reader already has one, or a photo?)
This makes it REALLY useful for moving heavy loads; it's a rigger's favourite. They generally use a crowbar or pinch bar for the toggle.

Another of the dozens of applications is for remotely releasing lashings


(as for example in the case of the notoriously controversial trailing line which trips the self steering or tiller line when you grab it after falling overboard)

In such cases the toggle is best made from a gently tapered item: a seacock plug, a fid, podger or similar. The tripline needs to be led from along the approximate axis of the tapered shaft, using a snatch block or whatever.

If you use a breakable toggle, it can be an excellent tension fuse.

I have used a carrot in this role... which possibly helps explain why rabbits are such bad luck on sailing ships, particularly French ones....
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Old 27-05-2013, 16:05   #3
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Re: In defence of the sheet bend

The way I learned it, the sheet bend is useful when joining two ropes of dissimilar size. Otherwise, the square know would always be superior.
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Old 27-05-2013, 16:11   #4
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Re: In defence of the sheet bend

That's why it is called a sheet bend....traditionally to attach a sheet to a sail. Two different sized lines essentially.
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Old 27-05-2013, 16:37   #5
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Re: In defence of the sheet bend

Hopefully eventually someone will come along and read the post, rather than the title....

Responding to the point raised, I used to think the sheet bend was uniquely suited to varying sized ropes, but there are better bends which are claimed to share or exceed its capabilities in this regard

I'm not familiar with Bash's 'square know' so I can't comment ;-)
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Old 27-05-2013, 16:40   #6
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Re: In defence of the sheet bend

Can you illustrate how you use a sheet bend to attach a snubber line to an anchor chain? As far as I can tell, reading various knot books, it wasn't designed for that type of use, and frankly I can't imagine how you do it.
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Old 27-05-2013, 17:16   #7
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Re: In defence of the sheet bend

Kettlewell

I kleimheist a sling (in my case, a webbing sling) to the chain, then use a sheet bend to the loop of the sling.

The sheet bend uses the existing loop to make up one half of the bend, so the snubber line essentially comes into the loop, then simply does a 270 deg turn on the way out.

(Except, because I only go to this much trouble if I'm expecting a 'combat situation', I usually make it a double sheetbend, for security

.... but otherwise like the middle photo above)

I don't have a photo of the combo, but here's the sling on the chain:
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Old 27-05-2013, 17:24   #8
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Re: In defence of the sheet bend

OK, I thought you were saying you used the sheet bend to attach the line to the chain. As I have said I have never snapped a snubber, and my rolling hitches don't slip, so I don't see the need to make it more complicated.
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Old 27-05-2013, 17:24   #9
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Re: In defence of the sheet bend

In theory, you could tie a sheet bend directly to the end of a chain link, by treating the link as if it were the end of a sling

(easiest if it's the end link, but not essential, if the chain is a reasonable size in relation to the cordage diameter)

I make no claim that it's a good proposition for strength or durability, but it's quick if you want to, say, secure a loose end temporarily and adjustably.
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Old 27-05-2013, 19:40   #10
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Re: In defence of the sheet bend

Loop made up with a Carrick bend and attached to chain with klemheist knot. 5/8" nylon Snubber of 50 feet attached with double sheet bend.

I am sure that I will receive a proper flogging for saying so, but I just cannot bring myself to use a snubber of less strength than the rest of the rode. To me, the real value of a snubber is in extreme conditions. If I am not around (or able) to change out a wimpy, light weather snubber that vaporizes just as things get interesting, then what was the point?

I most often do not use any snubber at all. In light to moderate conditions, it is not neccessary as I am not bothered by chain noises and Panope does not sail at anchor. Our anchorages in these parts are all deep (lots of tide) and I use lots of heavy chain so perhaps catenary is absorbing snatches that others on shorter rodes would find unacceptable without a snubber.

Anyhow, lets call this my "heavy conditions" snubber. It is so far untested except for some very energetic back-downs at 3 or 4 knots. Very exciting when things come up snug. The sheet bend seems to perform fine.

Steve
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Old 27-05-2013, 19:44   #11
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Re: In defence of the sheet bend

Quote:
Originally Posted by Andrew Troup View Post
I'm not familiar with Bash's 'square know' so I can't comment ;-)
Ah. You probably grew up as one of those kids who called it a "reef knot."

Same thing. Still superior to a sheet bend for similar-sized lines.
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Old 27-05-2013, 19:51   #12
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Re: In defence of the sheet bend

OK, for the specific application I was doing today, what is the best knot? I have a spliced loop in 1/2" dyneema and I want to join a piece of 11mm climbing line to it. It can be 'permanent' . I don't have to untie this. Ideally I think I would put a splice in the climbing line and cow hitch the two splices together . . . but lets say that I can't splice the climbing line. Then what is the best way to join the end of the climbing line to the spectra loop? I used a double sheet bend, but it sounds like perhaps there are better higher strength knots for this.
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Old 27-05-2013, 20:32   #13
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Re: In defence of the sheet bend

How about this? (see attached photo):

Pretend the blue line is your dynema loop (I have looped it using a zeppelin bend, and Kleimheisted it around the hammer). Give the loop a half-twist and then tie a Carrick bend with your climbing line. The Carrick is strong and secure.

Me, I just use nylon 3-strand in a rolling hitch around the chain. But I've never had to endure storm conditions at anchor...
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Old 27-05-2013, 20:49   #14
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Re: In defence of the sheet bend

Quote:
Originally Posted by estarzinger View Post
OK, for the specific application I was doing today, what is the best knot? I have a spliced loop in 1/2" dyneema and I want to join a piece of 11mm climbing line to it.
Oh gosh. Someone, apparently, never read my paper, "Twelve Common Knots Every Sailor Should Know for Joining High-Modulus Line to Climbing Rope."
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Old 27-05-2013, 20:57   #15
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Re: In defence of the sheet bend

Let me take this opportunity to point out what happens when sheet bends and dyneema mix: Dyneema line fails, causes NASCAR damage
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