Soft Links Vs Mallions

Tommy

Active member
In paragliding and also kite boarding (I believe), many modern setups eschew metal connectors between the harness and glider in favour of softlinks. Every gram counts and it seems the fabrics used are reaching a practical limit in terms of g/m^2 so manufacturers are looking elsewhere to save weight.

E.g. https://flybubble.com/shop/accessories/hardware/soft-links

Might such a connection be useful for extreme alpine cave rigging, where the benefits would potentially multiply far beyond 2 connection points to tens or hundereds?

Clearly fabric to fabric friction may be a concern, I highlight that such connections are used for reserve parachute bridle connections, though o-rings are used to keep things snug to limit shock loads, but these can be high g scenarios.
 

Bob Mehew

Well-known member
Some work is being done on the concept but nothing as yet to report.  We are however extending the capability of the Bradford's rope test rig kit to cope with the higher shock loads involved, as well as figuring out how to get useful answers.  Like most rope work, the initial 'suck see' gave a spectrum of results, though they did not rule the concept out. 
 

Benfool

Member
Something similar is already being used. AS hangers.....

https://starlessriver.com/shop/rigging_and_bolting/amarrage_souple

B
 

Tommy

Active member
Benfool said:
Something similar is already being used. AS hangers.....

https://starlessriver.com/shop/rigging_and_bolting/amarrage_souple

B

Ah yes, I did think of the AS hangers but I thought they were to be used with metal connectors to the rope, thus only saving the weigh of the rope loops in the rigging.

I didn't realise they were intended to be tied direct. Cool! I've just had a quick flick through the section on their use in Alpine Caving Techniques.
 

AlexR

Active member
Funny you should mention it now, I brought the idea to Bob a couple of months ago. Soft shackles are now fairly widely used in marine (sport) applications, and spreading. As he said, we've been testing samples/ concepts, inc. soft shackles. There are certain issues, especially when it comes to sharp edges.

Before you go and tie one/ buy one to use for caving, I should warn you that the spread of breaking strengths is considerable. There are also a wide variety of tying variations, with breaking strengths varying from 80-230% of single line strength.
 

Pony

Active member
Been used in slack lining for some time, and in the Yosemite situation, as well as playing in the park. Check out How Not To Slackline on YouTube. Everything from construction to destruction, it was these guys who got me going "Hmm, I wonder..."
 

Mike Hopley

New member
Rigging with 5mm dyneema cord and AS is a long-established practice. Plenty of testing has been done if you're prepared to look beyond the end of our collective noses.

See the EFS Technical Guide for an explanation of modern practice. For testing and additional safety considerations, see these EFS tests on dyneema.

I use dyneema all the time, and AS rarely. Obligatory disclaimer: like anything else, dyneema must be understood to be safe. There are some rules of use. Read the books.

Dyneema cord is essentially just a better sling in every way. A good length is about 3 metres of cord. Tie the sling fresh every time (using a figure-8 in expansion with 15cm+ tails), giving you exactly the length you want. Untie it when derigging. For very long slings, make a longer piece of cord by tying the ends together.

AS are very versatile, but obviously not much use on a resin-anchored route! Advantages include light weight, ability to extend straight over a rub point (unless it's a razor blade!), and ability to be used safely with any anchor placement (even in the ceiling). I would describe these anchors as specialist, whereas dyneema cord itself is more generally useful.

When using AS, the general idea is to tie in directly to the rope. However, depending on the method chosen, this can "throttle" the knot loop and make it quite difficult for people to clip their cowstail in. It's good to understand the multiple options for tying, but also consider using a few carabiners to make life less awkward.

I've just had a quick flick through the section on their use in Alpine Caving Techniques.

Note that things have moved on since the days of Alpine Caving Techniques -- there are safer and more efficient rigging options (see the EFS Technical Guide).
 
I've come across a rope rigged down Gavel on soft links (short braided lengths with a "monkey's fist" passed through a loop).  So someone is using them.
 

MarkS

Moderator
I think they are also widely used in sailing.

We have pondered soft links/shackles for unavoidable fixed rigging in Rowter. There are about 30 anchors on pitches that cannot be accessed from above, and long-term choices seem to be stainless maillons ($$!) or some sort of dyneema connectors.
 

Benfool

Member
Matt, that could be a well known dales diver, who was diving at the bottom for a while.

When he leaves caves rigged, he often does it "Russian Style" where you leave the rope in, but remove all the metalwork - replacing it with short loops of rope which you use to tie the rigging into the bolts. When you return, you replace each loop with a krab, meaning you dont need to rerig the cave. Means that people dont rob your krabs and avoids galvanic corrosion.

He did the same in Brownhill for a long period.

B
 

Mark Wright

Active member
AlexR said:
There are certain issues, especially when it comes to sharp edges.

I work in the Superyacht industry and soft shackles are common for many applications. I witnessed a load test of a ?1M tender last year and the soft shackle snapped over a sharp edge inside the tender. It only dropped 2m but the tender had to be replaced at ?1M.

Liros is probably the most common make in the yachting industry but they aren?t certified for man-riding and usually carry no EN certification or even have a CE mark so you can never be sure of the QA systems in operation at the factories where they are manufactured.

I use the paragliding ones in the original post on my paraglider.

Mark
 

Pony

Active member
Another consideration is what are you wanting to gain?
For instance this year I've changed over from steel mallions to alloy krabs, because (a) less weight and (b) I can afford them. With soft shackles the cost will probably be just under a mallion, weight deffinately so, though that said I wouldn't want to rig Juniper Gulf traverse with them.
 

Mark Wright

Active member
I?m not sure about the weight benefit of a typical alloy carabiner over a 7mm long M/R. I would have thought the carabiner was heavier? M/Rs are a lot less bulky than carabiners.
As for the price benefit of a soft shackle, I don?t think there is one. The soft shackles on the paragliding site that Topimo mentions are ?10.00. The Liros soft shackles are 
nearly twice the price, though they are primarily used for yachting which generally significantly increases the prices of things.

Mark
 

langcliffe

Well-known member
Mark Wright said:
I?m not sure about the weight benefit of a typical alloy carabiner over a 7mm long M/R. I would have thought the carabiner was heavier? M/Rs are a lot less bulky than carabiners.

The main advantage of carabiners is that when one gets to a certain age, they are easier to handle with arthritic fingers! I don't have the finger strength for stiff maillons any more.
 

Tommy

Active member
Mark Wright said:
As for the price benefit of a soft shackle, I don?t think there is one. The soft shackles on the paragliding site that Topimo mentions are ?10.00. The Liros soft shackles are 
nearly twice the price, though they are primarily used for yachting which generally significantly increases the prices of things.

Mark

Paragliding gear is another victim of poor economies of scale and some willingness to spend. The cheapest helmets are 3 times the price of a ski helmet despite being basically the same...
 

Tommy

Active member
langcliffe said:
The main advantage of carabiners is that when one gets to a certain age, they are easier to handle with arthritic fingers! I don't have the finger strength for stiff maillons any more.

Another is the idiot and abuse proofness. Bloody rusty bent gritty mallions... Much better to have a nice screwgate imo.
 

Fulk

Well-known member
I?m not sure about the weight benefit of a typical alloy carabiner over a 7mm long M/R. I would have thought the carabiner was heavier?

I just weighed 2 dozen maillon rapides and 2 dozen assorted alloy screw-gate krabs ? the former weighed 3 lb 2.75 oz (1439 g), the latter
2 lb 14.75 oz (1325 g), so the karabiners are ~8% lighter. (Well, someone had to  :))
 

Mike Hopley

New member
Mark Wright said:
I?m not sure about the weight benefit of a typical alloy carabiner over a 7mm long M/R. I would have thought the carabiner was heavier?

Steel 7mm maillons are 60 grams. Some screwgate carabiners are heavier, some lighter. I use Edelrid Pure Screws, which are 43 grams. The main reason for using them is better handling than a maillon.

For the bold/rational/demented (delete according to preference), snapgates are even lighter and nicer to use. Camp Nano 22 is my favourite ultra-light carabiner (22 grams).

Aluminium maillons are also available, such as the Petzl Speedy (23 grams). These are less strong, though still strong enough for caving if used appropriately.
 

topcat

Active member
langcliffe said:
Mark Wright said:
I?m not sure about the weight benefit of a typical alloy carabiner over a 7mm long M/R. I would have thought the carabiner was heavier? M/Rs are a lot less bulky than carabiners.

Going from memory ...7mms long maillon 72g and my rigging screwgates 38g.  And so much faster and easier.

I keep a few maillons for surface rigging.  And use soft rigging where possible.
 
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