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Old 26-10-2005, 06:05   #1
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Anchoring Technology - Yale Cordage

“Anchoring Technology” ~ A White Paper (20-pages) Produced by Yale Cordage
This is an interesting and informative paper which deals mostly with how chain, 3-strand nylon rope and the new 8-strand "brait" affects your anchoring performance.
Includes:
"The Physics of Rope & Chain"
"The Math bhind the Physics of Rope"
http://www.yalecordage.com/html/pdf/anchoring_tech.pdf
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Old 26-10-2005, 09:55   #2
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Quote:
New 8 strand "brait"
What is new about this rope? - other than perhaps this particular manufacturer having decided to make it! And why a new name - it has been known in Europe for a long time as Octoplait.

The benefits spelt out in the document are correct. I have had 3 strand nylon and octoplait and much prefer the later - and have recommended it on here a number of times. It's advantages:

It is a delight to handle by comparison to 3 strand.
It stows in a much smaller space.
It doesnt kink.
It is easy to splice, and the rope/chain splice is neat and strong
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Old 26-10-2005, 12:13   #3
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Brait

I have found the brait very difficult to splice. The technique is not difficult, but the strands are very difficult to open for the first three back splices and impossible after that. Three strand is much easier because it can be twisted to open the strands. The rope chain splice is rather bulbous and hangs up in my chain gypsy. Other than that, I have used it all summer with excellent results. I have 250' spliced to 100' of 3/8" chain and it has made anchoring a pleasure.
Jim
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Old 26-10-2005, 12:27   #4
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You should not need to open the individual strands

Instructions for an eye splice
Octoplait to chain splicing guide
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Old 26-10-2005, 19:42   #5
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Talbot,

From the looks of the Octoplait it's much courser then the new Yale Cordage. The outer surface is more flush on the Yale.

They just started selling the Yale here (that I could find) last year.

But either one I like better then three strand. The three strand twists while hauling anchor. By the time I get the chain to the windless the chain has a twist in it too. Then I'm fighting the chain onto the gypsy.

.................................................. ..........._/)
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Old 27-10-2005, 02:47   #6
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3 strand twists - this is not just a problem with getting chain to the gypsy. but has two other bad side-effects.

If you put the rope away before the stretch works its way back out, it can cause a real muddle in the locker so that getting the rope back out is a problem without having knots.

if the 3 strand is under extreme load, and this suddenly releases, the rope tries to wind itself up again, but fails, and you end up with kinks in the strands. This not only weakens the rope considerably, but will also prevent it from working through the gypsy.


Personally I have a warping drum on my windlass for the rope and haul in until at least 1 turn of chain is on the drum. I then constrain the chain on deck with a nipper to the central cleat, while transfering the chain over to the gypsy. Never liked running rope through a gypsy as I reckon it wears badly and weakens the rope.
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Old 27-10-2005, 03:17   #7
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Who are the European manufacturers of multiplait (Octoplait) ropes?
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Old 27-10-2005, 03:24   #8
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Gord, I think there are several. Marlow is the big one in the UK.

I'd welcome a comment about the relative strength of 'Brait' et al. I notice Yale's 'white paper' compares their Brait to 3-strand and that they have approximately the same breaking strength (Brait a bit less). But double-braid nylon's breaking strength is 50% more than Brait - see e.g. http://www.samsonrope.com/home/newre...fm?ProdNum=158 I ask because I've considered swapping the short length of nylon line on my #1 rode for either 8-strand or double-braid in order to gain more room for add'l chain in the locker. I picked up some double-braid nylon by Marlow last winter for docklines and have been very pleased with it. Why wouldn't I want more strength as well as easier handling in a more compact form?

"Octoplait" - doesn't that explain why they changed the name? <g>

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Old 27-10-2005, 14:37   #9
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Three major rope manufacturers available in UK:
English Braid, Liros, and Marlow.

Comparison of Breaking Strain of 14mm ropes:

English Braid
3 strand 4900 Kg
Octoplait 3800 Kg

Liros
3 strand 4100 Kg
Octoplait 4100 Kg

Marlow
3 strand 4850 Kg
Octoplait 4670 Kg


BTW Octoplait is from the Latin Octo for 8 (8 strands in the plait)Liros at least has another name for it, but it is known universally in UK as octoplait
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Old 27-10-2005, 17:15   #10
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Euro Cruiser

Euro Cruiser asked why not use double braid nylon which is stronger than the same diameter 3-strand or Plait. There are two good reasons:

#1 Double braid nylon stretch is significantly less than that of 3-strand and it is the stretch that we need to absorb shock loading caused by waves, surge, and wind. Otherwise we would all merely use Dacron and do away with the problematic chafe attendant with nylon caused by stretching under loads around objects. Double braid docklines look and feel good but they are not as good as 3-strand or 8-strand or 12-strand nylon due to lack of good stretching, especially when you consider that most people oversize their nylon docklines which puts significant strain on cleats, etc.

#2. Forming an eye in double braid is difficult at best to run "home" in the final steps. Forming an eye in a used weathered, salty, stretched double braid is all but impossible and, therefore, renders many lines useless once an eye is damaged. Such problems are not as significant in Dacron double braid because the eye can last the life of the line due to Dacron's ability to not stretch much.
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Old 27-10-2005, 17:35   #11
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Jentine and Talbot

I agree with Talbot's comments and, thanks for the link to the nice splicing photos.

Jentine, you might consider eliminating the nylon rope-to-chain splice altogether. I've never liked letting nylon fibers stretch against chain. A stronger method is to make up a Dacron pendant by forming an eye splice into the last link of the chain using the largest diameter double-braid Dacron possible. Form an eye in the other end of the Dacron to accept an eye formed in your nylon rode (3-strand, 8-strand, or whatever). Such a "join" looks like a square knot in appearance and, in both the case of the Dacron and nylon, the resultant strength is quite high due to the fact that there are two diameters of material carrying the load at the eye splices, including at the chain.

The only caveat is to make sure to use a length of Dacron sufficient to work and run home both of the eye splices, around two meters for 5/8 inch Dacron. Of course you can use more to make it even easier.
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Old 27-10-2005, 18:29   #12
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Plait splice

The splice I used, with some variation is the Direct Eye Splice. The only variation I used was to wrap the chain with leather thong(for chafe protection) prior to wrapping the line in alternating directions. I employed the following instructions:

"Rope to Chain Connections ?
ROPE to CHAIN CONNECTIONS:

There are a variety of ways to connect a Nylon Rope Rode to an Anchor Chain:

1. THIMBLED EYE-SPLICE
In most cases, this is accomplished using an eye splice around a thimble on the line, and a galvanized anchor shackle. This arrangement is strong and protects the line from chafe where it joins the anchor chain.
Unfortunately, it is difficult to pull using an anchor windlass, since the thimble/shackle cannot be pulled using the capstan or gypsy of the windlass. In most cases, the anchor rode will have to be temporarily made fast while the anchor rode is moved from the capstan to the gypsy. This can be hazardous, and overrides are common.
The other problem is that it is difficult to pass an eye and thimble below decks, unless a large chain pipe is used. It is virtually impossible to construct a self-tailing/self-stowing windlass system when using a thimble and shackle.

2. DIRECT EYE-SPLICE
Instructions @ http://www.yalecordage.com/html/pdf/...ain_splice.pdf

Many Windlass and Rope Manufacturers recommend a rope to chain eye-splice, consisting of a relatively common eye splice through the last link of chain. The line is seized about 12" from the end, the strands are parted, and two strands are passed in one direction through the link, while one strand is passed in the other direction. The strands are then spliced using normal technique. Various tapering methods can be used, but Simpson Lawrence recommends three full tucks, then two additional tucks made with half-diameter strands. This makes a compact, rapidly tapered splice, that retains about 75 - 85% of the rope’s original stength.

3. PLAITED EYE-SPLICE
Instructions @ http://www.bluemoment.com/warpchainsplice.html

1. From the end of the rope count twelve turns down the lay and mark the twelfth.
2. Make a constrictor knot with the waxed sail twine just after the mark and separate the stands up to the constrictor knot
3. Insert the first strand (blue) into the first chain link
4. Insert the second strand (red) into the first chain link from the opposite side of the first strand. Draw up the two strands tightly to keep the constrictor knot snugly against the first chain link.
5. Insert the third strand (white) into the second chain link
6. Insert the first strand (blue) into the second chain link from the opposite side of the third strand.
7. Insert the second strand (red) into the third chain link.
8. Insert the third strand (white) into the third chain link, from the opposite side of the second strand. Draw each strand up tightly at each pass and continue on the same way until you reach the end of all the strands and finish whith a small constrictor knot on the sixth link). Seal the end of each strand with the hot knife.

I've never used this "plaited" eye-splice, and wonder about it's efficacy.

Does anyone have any significant experience using , or know of any tests or reports, about the “Plaited” Rope-Chain Splice ?

Any other advice, recommendations, experiences, references, or comments etc...?

Thanks & Regards,
Gord "
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Old 27-10-2005, 18:55   #13
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Rope

I believe the US Navy stopped using nylon for anchor lines after a fourth seaman was killed after the splice snapped and the line recoiled and hit him, as it had the three previous.
They then switched to polyester, and the splice was changed so the the last exit piece exits further down the line and not at the eye or joining part of the splice.
This story was told to me by a rope guy at the Chicago boat show about 1981. He also showed me the new splice.
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Old 27-10-2005, 20:05   #14
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Hi Jentine,
Using the aformentioned Dacron "interface" the entire strength is essentially the same strength as the line.

BTW regarding the instructions from bluemoment.com I've been told repeatedly by riggers that it is considered bad quality to use a hot knife. The melted fibers can cause chafe to other fibers, are obnoxious at the least, and eventually cause breakage of the fibers just like soldering can cause wire strand breakage.

BC Mike C: It would be interesting to know what is the splice method used by the US Navy. Do you have a source for the illustration?
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Old 27-10-2005, 22:17   #15
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Splice

I asked the rope guy to show me the splice as I wrote notes. I still have the notes and that is how I splice the stuff. It is essentially the same splice as shown in the Sampson book but the last tail does not exit at the joint, it exits further down, about two inches.
I may be dated a bit on this as I have not looked at a Sampson guide recently, I just keep splicing using my old hand written instructions. I would be pleased to post them but they will not make any sense to someone who has not spliced this double braid line, and who has not used fids.
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