More hyperbole. While the old test results I cited suggest
that the point of interlinking eyes was the break point
–at least, there were differences between differently
joined (mere reeving vs. square-knot-like joint) eyes–,
we’re not seeing that point as a break point here.
And what I’m saying above is in response to something
I thought you’d insisted re “bight” legs in always being
of equal load : no, if an imbalance is introduced by how
the knot compresses and feeds material into each leg,
the friction at the joint of eyes will inhibit equalization
of forces on the legs.
On the other hand, we’re still talking about roughly half
of the force that is borne by the SParts, so the eyes should
not be critical points. (But it sure would be nice to under-
stand how that old test data came to be different --maybe
it just was of few cases and not so much difference to be
explained as normal variance? Rope was relatively thick.)
The results of the average strengths of each "summed" eyeknot will be lowered quite a bid, when this weak link/point/area will be taken into account in theory, or when it will be included into the compound bend in practice. This was one of my arguments against the validity of the general statement of J.P., right from the start ! I even predicted an as high as 50% reduction of the system of two linked eyes, in relation to a system of two unknotted lines - just because of those sharp U turns at this point/area, that are completely "naked", unprotected by any deflexion (in their vicinity) that could possibly absorb/dissipate the loading .
And here I completely reject this opinion : again, the tension
in the eye legs is half (roughly) of that in the SParts
–it should not be a weak point unless the knot is strong.
J.P., I think, is not finding it so in his material & knots.
So, my gut feeling told me to bet at a 50%,That's a good feeling, but, again, it's 50% OF 50% ! --i.e., the force delivered here is half that to the SParts.
[quote="Dan_Lehman post:94, topic:4623"] The essence is the proposition that, given the seen-here test results for several eye knots and some end-2-end knots, eye knots [b]are sufficiently stronger[/b] that [u]it would be stronger to join lines with a pair of them than a single end-2-ender[/u]. [/quote] That proposition is wrong because of many reasons, so it is of no use whatsoever to [u]conceal[/u] it as if it is "deduced" from / forced by the experimental data -- because [i]unperformed experiments have no results[/i]. The "given" ( performed) experimental data were only for the one-member links ( the [end-2-end] knots /bends and the eyeknots/loops ), not for the two-member links ( the linked eyeknots).The phrase “given the…” - " it would be…" connects performed to un-performed experiments
–and I had already lost many of the few remaining segments of my life line arguing that this is WRONG !
Yes, there are unperformed experiments; but there had been
unanalyzed-fully results of the data at hand --which I have now
laid bare with statistical analysis. (And I should say that the
volume of experiments etc. certainly is limited; but we do have
at least some analysis to make from what has been done,
beyond merely looking at the averages.) The implications
of the particular values of mean and standard deviation
support the proposition, at this stage of data --nothing more,
but nothing less, either.
[quote="Dan_Lehman post:94, topic:4623"] I have remarked that this also can be done with the [i]"twin"[/i] eye knots end-2-end joining, as well as with the direct interlocked eyes : that the loading profile is the same [/quote] Yes, indeed, the loading profile is the same... BUT THE KNOT IS NOT ! In comparison to "twin" "eyeknots" ... , [u]ex-eyeknots where each of the two legs of each former eye has now been [b]"cut and pasted"[/b], in order to be connected to its twin )[/u], the genune linked eyeknots have ONE MORE WEAK LINK --and this link is very weak, indeed : [u]the point/area the eyes are linked together I was talking about above[/u].
Whoa, you’re well off the track, here. Please confer ABOK #1454
–which seems to be the sole instantiation of the “twin” concept–
for what is meant; there is no “cut and pasted” part (whatever
that could mean), and in fact the inter-reeved-eyes point is gone
–just pure knots loaded the same as “eyeknots” are (we should
think).
..., sorry, I am knot going to calculate the reduction of strength we should expect due to the "weakest-link" situation in the case of three links !No one's sorry about skipping this gratuitous exercise, although it could be edifying for one who has so far so eschewed applying statistical methods to the data --except that, here, so far, the data for the inter-eye points has been a clean 100% non-failing.