Re: Something interesting about splicing BeeLine...
...The question: When you're doing the standard double braid splice in the 8mm stuff, how long are the cover and core tails? Are you sticking with the same measurements as polyester would call for, or are you lengthening things a bit.
I can't wait to hear what the break test reveals.
I did the polyester measurements - here's my rationale: First, for the purpose of a split tail, it is not necessary to maximize the strength of the splice. Bee Line is rated at 8000 lbs - I certainly don't need 8000 lbs for a split tail. Even if the splice provided 5000 lbs, or 63% of Bee line's strength, that's way more than most 8mm cordage. The earlier pull tests I did on 8mm locked brumel splices indicated an initial failure at about 5000 lbs. These were the 'standard' brumel splices with a 6 - 7 inch tucked tail. Plus in the common closed split tail, there are two strands and hence two splices sharing the climber's weight.
I also found that a tucked tail using the cover only, was about as strong and secure as the locked brumel in the core. Hence the cover can provide surprisingly high strength. However, as you know, in a locked brumel splice, the core carries 100% of the load and the cover contributes nothing. But, in a double braid splice, again as you well know, the cover is tucked into the core, and the core is tucked into the cover and both then tucked into the cover. This means that both the cover and core are sharing the load.
It is extremely interesting that in my pull tests, the locked brumel core held near 5000 lbs; the tucked tail cover only held right at 5000 lbs. This suggests that the cover plus the core in a balanced condition should support nearly 10,000 lbs which is 2,000 lbs more than 8mm Bee Line is rated for.
I said all that to say this: with all the tucking in a double braid splice, IF THE CORE AND COVER REMAIN ESSENTIALLY BALANCED, the double braid should be much stronger than a locked brumel, but only a pull test will reveal if this is true or not. Further, in the double braid splice the cover protects the core completely.
Since I don't have a way to attach the non-spliced end of a rope except with a knot on our tensile machine, I'll likely pull a double braid I2I and see where it fails.