Dyneema soft shackles

Boreades

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I've only just heard of dyneema soft shackles, and am much impressed by them, mainly because of the risk to my children of stainless steel shackle & blocks banging them on the head while they try to help. Has anyone used them? Are they good enough? Links to online sources?

Thanks
Keith
 
Soft shackles

I was most impressed a few years back to be in Hobart at the finish of the Sydney to Hobart race to find that the bigger 100 ft maxi boats used attachments which I think are what you are talking about. Indeed on a large boat (Leopard) the only stainless steel to be seen was in the stanchions and life lines. Large pulley blocks were attached by dyneema wrapped around several times and even stays were of a sysnthetic rope.

The connections for halyard consists of an eye splice in the end of the halyard. Dyneema spectra etc. A pin of stainless steel or Ali goes through the eyesplice. This is housed in a fibreglass tube about 50mm long so the pin sticks out both sides of the tube. A piece of dyneema/spectra is spliced into a circle about 80 mm in diameter which is arttached tightly to one leg of the protruding pin. The ring of rope is passed through the eyelet of the sail and slipped back over the other protruding end of the pin.A wrap of cloth with velcro is attached to the tube so that it can wrap around the whole device including the ends of the pin to hold the ring of rope in place.

The advantages are light weight and the velcroed cloth wrap can be removed and refitted easily with gloved fingers in difficult conditions.

So I don't know what is available commercially but it seems to me that you could make something similar. I tend to just use a bowline on the end of my halyards. Lighter weight and the knot goes in a different place each time so halyard wear point is varied. olewill
 
http://www.colligomarine.com/

You can get them there. I see Multihull world magazine just ran an article on how to make them. I have made them and used the Colligo ones. They set the knot with a machine I think, not sure. I love them! I have found places I never thought I would use them. Soft hanks, halyard shackles, tack shackles, to secure all my deck blocks for my sheets, and even replaced my big snatch blocks on the bows of my Trimaran for an anchor bridle. The uses are almost anywhere where you use a shackle.

I also converted my entire rig to synthetic Dynex Dux. Took 20 kgs. of weight off up high and have a much nicer sailing boat. Pics at the URL

http://tinyurl.com/m7orsv
 
Knot

If you do get some, don't rely on a bowline, it is slippery stuff. I believe a tree surgeon died when the knot came loose. There is a fairly simple splice they use with the stuff, I would love to replace my lifelines with it.
 
Not being a slacker, more of a crash test dummy....:-)

I should have mentioned I am trying to destroy this stuff. No really..... give it a go! I did not file any sharp edges just for that reason. I day sail most afternoons, so I get a lot of up and downs on the gear, but no overnight worries. I am not really trying to be un-seaworthy. Same thing on the bow fairleads. After 3 months on the hook in front of the house, the rope had "flat" spots, mostly from being pressed against the deck and non-skid. I had John at Colligo check them out. He massaged them back to new life, no visible wear.
I started out with life lines and running backstays. 5mm Dynex is so strong! I switched all my halyards to it after the life lines. In the last 3 years I have eliminated wire on my boat. And a bunch of steel shackles. And a bunch of weight. Do not mistake Dynex, for Dynex Dux. You cannot use Dynex or any other SK-75 (Amsteel, Spectra) for standing rigging. Needs to be heated and stretched as DUX is. Works great for replacing wire and is 1/3 the cost of exotic stuff and a lot more durable....
The splice is not difficult. Being a hollow core, it is simple to bury after doing the proper tucks. Good illustration here. Below Careful though....this stuff will change your life....sorry if I got excited there...can you tell I like the stuff........:-)http://www.colligomarine.com/docs/misc/splicing_instructions_for_web_rev_1_2.pdf
 
If you do get some, don't rely on a bowline, it is slippery stuff. I believe a tree surgeon died when the knot came loose. There is a fairly simple splice they use with the stuff, I would love to replace my lifelines with it.

Brion Toss (a well known rigger Briontoss.com) just reported they ran a series of knot tying tests with our Coast Guard guys on the SK-75 line. He said every knot slipped out at 10% or less of the working load....Only one held beyond the 10% mark. He did this to show the coasties how this stuff looks like rope, and kind of feels like rope. But it is not to be treated like rope. It is twice as stong as wire, but you CANNOT tie knots in it. A good stopper knot is below.

http://www.colligomarine.com/docs/misc/CMRStopperKnot.pdf
 
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I've only just heard of dyneema soft shackles, and am much impressed by them, mainly because of the risk to my children of stainless steel shackle & blocks banging them on the head while they try to help. Has anyone used them? Are they good enough? Links to online sources?

Thanks
Keith

I have made some just to try them out.

I did no use the style of dynema that the commerial sellers use.

I used the sheath from larger rope and replaced it's inner with another dynema rope.

They are quite easy to make - No turks head or anything time consuming. I used odd pieces of rope I had around.

I have no jigs to check the actual fail strength so I have been quite careful in their use.

For the first one I spliced soft eyes at the end of each genoa sheet then use one of the soft shackles to attach the sheets to the clew. This has been in use from when I first launched this season. This is quite a good test as the genoa is 450 square feet. No troubles whatsoever with it.
The others have been used just to lash spare standing rigging to the guardrail.

I have also used one to attach the crusing spinny to it's hailyard.

As I get more confidence I will try them for more demanding tasks and will make more when I can find the time. I have had some requests from club members to make some for them.

The one disadvantage of them is that they tend to be longer than the compatable strength stainless shackles. Thus they sometimes are not directly replaceable.

The next time I make some I will post a series of photo's on the forum. That will not be for at least a month as I just don't have the time just now.

Compass do sell three sizes of soft shackles.

Iain
 
do them yourself

They are easy to make, have a look at the pictures here


http://sybrancaleone.blogspot.com/2009/02/un-grillo-in-tessile.html


you may change the final knot with another one if you want, but not one of those I finished with the simple knot has slipped.


Have a look at the variation at the end (the last three pictures), it can be useful if you need the "shackle" more securely attached to one of the fittings you are joining together.
 
As I was having my first cup of coffee this morning here in Oregon USA I could not help but think what an amazing thing this all is. Here we have guys from England, Italy, South Africa, Western Australia, and USA (Did I miss any?) Having a discussion.
We can fire photos back and forth, add our experience to the subject, pick apart or cheer for what ever is on the table. Amazing really.....
The trail for me went something like this. I talk to the Icelandic net company in Alaska to learn about Dynex Dux.(this is another story) They build the Rope in Lithuania, I receive it in Seattle, drive it to Mexico, Rig my boat while a number of folks from all over the world are watching and checking in with me.
Then we discuss it here all over the world.
Sorry for the philosophical prose today. Fact is I believe what a well know yacht designer told me recently when we were discussing my Dux Rig. He said "In a few years I will probably not design a boat with wire anymore"
 
They are easy to make, have a look at the pictures here


http://sybrancaleone.blogspot.com/2009/02/un-grillo-in-tessile.html


you may change the final knot with another one if you want, but not one of those I finished with the simple knot has slipped.


Have a look at the variation at the end (the last three pictures), it can be useful if you need the "shackle" more securely attached to one of the fittings you are joining together.



Roberto sono bellissimi, i tuoi nodi.

Absolutely brilliant. Winter project to self: prepare a bunch of Dyneema shackles to try out next season
 
Roberto,

I'm not overly keen on that approach.... its the knot in the end that bothers me.... its well recognised that Dyneema doesn't tie well, and that knot looks vulnerable to me.... I think it needs something more robust than that.... but don't know how to do it!
 
Some shots of where I am using "soft solutions" or where Dynex is replacing metal fittings.
The dark grey ones are soft shackles from colligomarine.com
I got the bright idea to try to make a similar fitting myself at the end of my Dynex halyard. It needs some work, it has slipped out twice. Probably have to build up the knot..... The Collligo fittings have never failed....:-)
 
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That looks better... so if spliced the two loose tails together, and then tied a 'Stevedores' knot, it would look a whole load more robust....

Yes....better in that it would not roll or slip out as well as adding bulk to the stopper. You get a better stop from you stopper.......:-)

I wish I had a book refrence to the "old way" of doing things. So many of the same functions were dealt with when all the had was hemp rope. Now we have this new supper light, super strong rope that we can find new/old ways to do the same things....:-)
 
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