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Making cowstails.. Rope age question

If the exact details of forces on cowstails with tight knots/loose knots/rope diameter etc. were that critical, then rather than arguing about small differences we should just be using shock-absorbing lanyards.

But we don't, because we don't need to, and it's a faff.
 
Bob's chart on previous page shows that for factor 1 & 1.25 falls on both short or long cowstails, the third drop hits about 1.5 times the peak force of the first drop, so it is significant, but we don't know how much of that is due to tightening of the knots & how much to damage of the internal structure of the rope. Fortunately it's very rare to actually subject a cowstail to a "clean" drop in use.
 
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