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Topic Date User

Ripped daisy bartack 17-Apr-2012 At 2:42:25 PM Hendo

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On 17/04/2012 mikllaw wrote:
>If you are always clipped into the same loop it could be simple wear. The
>stitching isn't in shear like a normal sling, but is being ripped open
>so most of the load is on the first line of stitching. I wonder if the
>stitching was able to be worn by the biner?

This comment is probably more along the lines of the reason for the failure. I haven't bothered to read through everyone's posts in detail, but it seems there have been various calculations of net forces, neglecting the fact that other (different) internal stresses (forces) are important and may be significantly high enough to cause failure. As Mikl said there would be come kind of stress concentration on the first line of stitching (continually applied to new stitches as the stitching progressively fails).

The rating of 3kN is a net force on the daisy (I would assume), but the internal stresses (forces) will vary with setup (biner radius, sharp edges, twisting etc). How much variation, I'm not sure (forces are often hard to calculate and work with) but loads closeish to 3kN could have different outcomes dependent on how it is applied. It is possible the 3kN rating may be a bit deceiving.