Re: Endless rope loops

Scott SV Tengah

Perhaps it's different on a Super Maramu, but the loops on a 54 are definitely not simple spliced loops.

When I opened mine to figure out how it was made, there were, if I recall correctly, at least 4 loops in there. So similar to legs of lashing, the more legs, the more strength. So the loops on my 54 are definitely stronger than 2x line strength. 

To answer Paul's previous question, I decided to replicate the multiple loops of white/gray dyneema with the black dyneema chafe sleeve over it.  My reasoning is that all of the loops I have replaced were due to the dyneema sleeve chafing through rather than the multiple loops inside breaking. That implies to me that the application is subject to some movement/chafing and a black cover on white internals makes it very easy to see when the loop needs to be replaced. If it was unprotected, I would have to more closely inspect for evidence of chafing.

Bill - how do you figure 400% theoretical and 300% tested on the soft shackle that you linked? In the written description that the video's author wrote, he tested it at 230% line strength, which is better than the typical 170% breaking strength of a regular diamond knot soft shackle, but not 400% theoretical/300% tested? The limiting factor is not the legs, but the eye, which you cannot eliminate.

On Fri, Mar 4, 2022 at 6:26 PM Bill Kinney <cruisingconsulting@...> wrote:
A properly made soft shackle will be stronger than a single loop. For reasons that I don't understand, a rigger would call a simple spliced loop of line a "gasket."

For making soft shackles this method is a bit more complex than what you usually see documented on the method to make these, but is proven stronger:  Brion Toss Soft Shackle

A soft shackle carries the load across FOUR legs of line, while the loop only has two. If the loop has a 100% perfect splice, the maximum strength it can have is 2X the strength of the single line.  A well made soft shackle is theoretically 4X the line strength, but realistically tests out to 3X.  

Given the pretty amazing breaking strengths of well made Dyneema line, this is really impressive. A 1/4" (~6mm)  Dyneema line has a breaking strength of 8600lbs (3900kg), which means a well made soft shackle made from that would have a breaking strength of almost 26,000lbs (11,700kg), much stronger than any stainless shackle you might consider using.  Two of those could lift your boat out of the water. More than suitable for pretty much ANY application on your boat.

Bill Kinney
SM160, Harmonie
Hollywood, FL

2007 A54 #69
SV Tengah

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