I am really curious, which of those two systematically ( I would say, relentlessly…) advertised/promoted loops is worse, regarding un-tiability. As they both include “closed” knots ( rope-made self-locking “tension ratchets” ), overhand / fig.8 knots tied on the Standing part before / after the eye, they are perfect examples of why the bowline ( and its derivatives) is the King of knots, while they are only some, let is say that way, would-like-to-become princes ( but, for the time being, “locked” in an altogether different kingdom 
).
Taking into account that they become difficult to untie too early, after they are loaded by a small, only, portion of the MBS of the knot ( perhaps because they were designed to do so in the first place…), as roo correctly points out, their testing is just plain realistic, and the tester would not “put [him]self at risk of serious injury”. Therefore, I wonder why nobody had performed this test till now ! This enables some really bad, malicious guys, who just practice “rubbish keystrokes of derision”, while they live and “work in a space w/o gravity or materials and just knot their minds tight against tangible aspects”, but only prefer to speak out the truth about the knots they had tried, to criticize those loops unfairly !
I will offer a pot with delicious raspberry jam to the need-not-be-so-brave knot tyer who will test those two distant-future princes of knots, and compare how difficult they can be untied even after moderate loading.
This enables some really bad, malicious guys, who just practice "rubbish keystrokes of derision", while they live and "work in a space w/o gravity or materials and just knot their minds tight against tangible aspects", but only prefer to speak out the truth about the knots they had tried, to criticize those loops unfairly !
Not sure about the taunts and vitriol but, I could give this a shot maybe on Sunday.
The problem Xarax is that all of these types of tests cost money and time.
And I have in general terms backed away from simplistic strength testing over the years. However, I do support strength testing if its well thought out and advances our understanding of certain knot geometries.
For example, testing single helix nipping structures against double helix nipping structures with both having the standard 2 rope diameters inside the nipping structures… And then - moving on to the 3 rope diameters inside a single helix nipping structure and then followed by 3 rope diameters inside a double helix nipping structure and so on… I would support this type of progressive testing to identify what effect one change has over another.
The other aspect related to strength testing that I support is zeroing in on what makes a particular knot structure jam resistant. So - while applying force to a knot, perhaps stopping at a certain milestone of force and then determining if the knot can still be untied (relatively easy) by hand - and without resorting to the use of tools.
I think I have some 7mm or 8mm climbing accessory cord lying around… I’ve still got a load cell and also a 2 ton lever hoist.
You see Xarax, a load cell is not cheap ($$$). Breaking larger diameter cord costs money and is not without risks and, it all takes time. Maybe that’s why you don’t see a lot of well documented knot tests??
It would so nice to test all those things, would nt it ?
I had proposed the 1/2. 1/3 and 1/4 of MBS of the unknotted rope as those benchmarks / milestones.
The problem here is that a knot can be untied using many “tricks” : by pulling bights, by rotating parts of the knot relatively to others, by pushing ends inward, etc. How can we tell if such a manoeuvre is “easy” or not ?
Let us be sincere ! It is NOT that ! I know dozens of sports and hobbies which require MUCH more money, for equipment, running expenses, repairs, etc. - and MUCH more time !
Our problem is that we are too few, period ! Knotting is out of fashion, young people just do not see the point of this activity, which seems akin to an era long gone and forgotten… Also, not-so-young knot tyers can not learn new tricks any more, they do not try to tie new knots, they try to convince themselves that they already know anything worth knowing, and they keep parroting the same things over and over again, in an effort to believe they are still alive.
P.S. You don’t need any load cell ! You can just use a hydraulic bottle, and record the pressure.
Well xarax, I was brave enough. However my results will be easily dismissed (by some) I suppose 
Both knots were tied and dressed properly I believe, I spent quite some time making sure I did both knots justice. I loaded both the Zeppelin Loop and the Lehman8 to slightly greater than 50% MBS (~100kg in my stiff 3mm braid). Both knots did not noticeable slip and were easily untied after this high load.
To put the above result in perspective: I also tied a Figure 8 Loop and loaded that to 100kg as well and now I cannot untie that knot by hand. In the past I have tied numerous bowlines and trialled them for jamming, all the ones I trialled could be untied. I have recently trialled some “constrictor” style (TIB, PET) loops in a recent thread only to find I could not untie those. I have tied the Zeppelin bend and heavily loaded it in the past and successfully untied it, though that was actually quite difficult. The point being is that my trials seem to support previous findings eg. Findings such as: Bowlines can be untied and the Figure 8 loop has the propensity to jam.
To answer xarax’s question, the Lehman8 was slightly the more difficult to untie, though easier than some of the bowlines I have tackled. I am starting to get a good feel for what jams and what does not, and some of the ‘why’.
If Mark does do some trials of the two knots above, in larger diameter rope, then I will be very interested in the result he gets.
Cheers,
mobius
LOL, I knew you would find a way to justify your apparent ignorance about these two knots.
The experience I had was that Zeppelin loop tightens on one side of the nub a lot more than the other, leaving the less loaded side easy to untie first. As for the Zeppelin bend, how would you know what the comparative ease of untying the Zeppelin bend vs Zeppelin loop is, you tell us you never trial knots? You have rubbished two knots for no good reason it seems and do not even have the good graces to acknowledge that you may have made a mistake. You originally were quite adamant that both knots were poorly constructed jamming knots and I have just provided empirical feedback that these two knots are very likely to both be just the opposite of that. Maybe it is time for you to start rethinking things?
As for my saying slightly more difficult vs slightly less easy, Dan can ask me about that if he feels at all affronted.
Cheers,
mobius
Edit: added an image of the version of the Figure 8 loop I trialled (and could not untie). I always had trouble with what the preferred version was supposed to be, I don’t think it is this one though. The collar nearest the eye remains relatively slack, though despite this the rest of the nub remains very solid and is way too tight to loosen by hand. I do not see why other versions of the Figure 8 loop would fair much better than this one under heavy load, in terms of untying them.
( Dan Lehman and roo would be really GLAD with your indisputable, incontestable deep knowledge of knots, in general, and of their superb knot-frog-princesses, in particular. And with the fact that you would had been able to untie / kiss them so easily - ( after you had loaded them with 100 kg ! )
THAT is a great advantage, indeed ! If you had added two more interlocked overhand knots on top of the already interlocked two ones, you would had been able to untie first the last one of them, even more easily !
( For the interested reader : I had pointed out that great disadvantage of the fake, so-called “Zeppelin loop” a number of times. :
tied [b]a [i]Figure 8 Loop[/i][/b] and loaded thatThis is the common text in general, and we are none the wiser about what geometry was involved --for any such knot, there are, as has been noted, [u]twin[/u] parts and which if these plays which role is left unstated.
As for my feelings re this test, I guess I could try
to deflate the higher flying zeppelin with some
missiles … , but it’s much what I might expect of
the two. In the balance, IMO the Lehman8 is the
more slack-secure of the two, and if it can be loosened
and untied in normal usage, that’s fine, no matter its
ranking.
As for any difficulty untying the zeppelin end-2-end knot,
I’d want to see the jammed structure : had it capsized
(as can the bowline)? For it, also #1408, should be
easily loosened in most cases.
–dl*
I notice the careful way you attempt to escape - almost silently !
Of course, if by “normal” usage you mean a light loading, and in the technical meaning of the verb “can”, the Lehman8 knot “can” be untied, indeed ( notice that, just as you do, I do not say : “untied easily” ! ). However, we should always keep in mind that the easiness or not of the untiability of a knot depends also on its shape, regarding the “handles” on the outer surface of the nub it offers to our fingers : Can we grab s bight / riding turn, and pull it out of the nub ? Can we “shake”, in a “fodling” way, or twist one part of the nub in relation to another, and move it back and forth or rotate it, until we loosen it ? Can we PUSH an end inwards, to feed material into the nub ? ( This depends also on the stiffness of the material - with soft, lengthwise compressible materials, we do not have this option ). Moreover, and I have to point it out here again, it depends on the SIZE of the line - simply because, to untie a knot without a marlinespike or another tool, we use out FINGERS !
Now, about the quality of this “trial”, which has no relation to a scientifically sound test / experiment whatsoever, you are right you keep silent. After all those years, it would be funny ( and unfair …) if you would had to defend the quality of your knot based on such attempts… I am sure you have tried this knot much more carefully than that ( and loads heavier than 100kg ! ), and you, too, like me, have realized that it can NOT be untied easily, and, of course, not as easily as most of the many decent secure bowlines we already have - but you feel some sentimental affiliation to your brain “child” from which you can not distance yourself… I understand that, and I may even say that I respect that ( after all, I suppose we are all humans - although I can not rule out the possibility that there are some robots walking/collecting money among us, too ), and this is one more reason I do not publish the results of the “trials” on the “new” knots I happen to tie ( and which, although they, too, can not be characterized as decent “tests”, they are less superficial ). It is difficult indeed, and perhaps impossible, for a knot tyer to be an objective judge of a “new” knot he had tied, and, with the years, he may even be willing to forgive some shortcomings if it, rather than forget the knot altogether - as I had suggested you should better do, with your infamous Lehman8.
No “escape”, by whatever hearing!
Rather, a putting into proper perspective
–and out of some inane “ideal” state.
This knot was intended for use by rockclimbers,
who have a known range of materials (for climbing
lines --note that when they included HMPE material
into support lines they gained unknowns!)
and forces (human mass in typical falls while (not
quite) climbing).
Of course, if by "[i]normal[/i]" usage you mean a light loading, and in the technical meaning of the verb "[i]can[/i]", the [i]Lehman8[/i] knot "[i]can[/i]" be untied, indeed ( notice that, just as you do, I do not say : "untied [i]easily[/i]" ! ).I don't think that the usage I'm looking to could be well described as "light". And esp. that done by Mobius (est. 50%) is [u]far[/u] from light --100kg being a big bite of available tensile strength. That you (X) should harp on this is really troubling. (And in contrast, when you even braved mentioning your own testing, you did not dare disclose your method and hence you loading %, et cetera!?)
As for “easily”, let’s leave it as "relatively easily,
in comparison to the standard tie-in fig.8 eye knot.
But there will be better/worse-set tokens of this knot,
as I remarked vs. Agent_Smith’s rather loosely set
knot (which he nonetheless was able to untie).
Beyond this, I think that one can take the tail
further into the knot so to inhibit the loaded
collar part from moving into a jamming position
(where it aligns with S.Part between it and a
part on opposite side and can tighten hard & pinch).
–dl*
As I understand, those ropes are not 3mm , and those forces are far lighter than the 50% of the MBS of the ROPES used by rockclimbers. I do not doubt that, on thin cords or under light loadings, even the Lehman8 eyeknot can be untied easily - but I was NOT talking about thin cords or light loadings !
Moreover, as I had mentioned time and again, knots are NOT meant to be used only by climbers ! In construction, transportation and boating, the applied loads are much more unpredictable, and can often reach such high percentages of the MBS of the ROPES on which they are tied.
IMHO, 50% is HEAVY loading, and I had mentioned it more than once - so you had failed to notice it more than once, too.
However, it is really troubling me, that you have not understood AGAIN ( or, that you still insist or pretend you do not understand ) anything about the reason this “trial” is dismissed by itself ! ( Especially when, under the same “experimental” conditions, the conclusion drawn were that the Zeppelin bend was more difficult to untie than the so-called “Zeppelin loop” ! )
We ( humans ), WE UNTIE KNOTS USING OUR FINGERS ! So, when the load by which we tighten a certain knot is so light ( 100kg ! ), we should not allow ourselves to jump into ANY conclusions about the easiness with which we may be able to untie it - simply because we can ALWAYS apply the weak force required to untie a lightly tensioned knot, irrespectively of what percentage of the MBS of the line this light load represents.
For a semi-static ropes used in many professional applications, the 50% of the MBS is 850-1900kg. See, for example :
http://www.beal-pro.com/2014-2/anglais/cordes-semi-statiques.html
Are you telling me that, if you can untie without much difficulty a knot tied on a thin 3mm cord, tensioned by 100kg, you will be able to untie the same knot, tied on a 9-12.5 mm rope, when it will be tensioned by 850 -1900 kg ? ( What else will you try to imagine, to defend a lost case and a better-be-forgotten knot, I wonder… Using a fraction of the time you lose in pointless keyboarding, I believe you could tie a better new knot ! )
P.S.
Noope ! The standard tie-in fig.8 eyeknot, does NOT represent the standard in the easiness of un-tiability of eyeknots ! The fig.8 eyeknot is difficult to untie after heavy loading.
The standard of the un-tiability of such knots is the bowline - when we evaluate an eyeknot regarding its un-tiability, we should compare it to the bowline - the comparison to the fig-8 eyeknot should be limited to security, IMO.
More stuff thrown by one who himself cannot bother
to describe his own trials
I do not publish the results of the “trials” on the “new” knots
I happen to tie ( and which, although they, too, can not be
characterized as decent “tests”, they are less superficial )
No, you don’t --neither results, or more important, method.
Rather, you whine about everyonelse’s (more “superficial” than vapor!)!
Are you telling me that, if you can untie without much difficulty a knot tied on a thin 3mm cord, tensioned by 100kg, you will be able to untie the same knot, tied on a 9-12.5 mm rope, when it will be tensioned by 850 -1900 kg ? ... [some deleted]In fact, yes, sometimes the smaller material is more of a challenge to loosen than the larger, as the larger gives fingers purchase; sometimes, no, it is as you suggest, a scaling problem --rope & forces scale up, but one's fingers are the same fingers.
But untying knots loaded well in excess of recommended
forces just isn’t one’s greatest concern --it would be why
such forces occurred : what has been mistaken!?
[quote="Dan_Lehman post:9, topic:5735"] As for "easily", let's leave it as "relatively easily, in comparison to the standard tie-in [i]fig.8 eye knot[/i] ". [/quote] Noope ! The standard tie-in [i]fig.8 eyeknot[/i], does NOT represent the standard in the easiness of un-tiability of eyeknots ! :) The fig.8 eyeknot is difficult to untie after heavy loading. The standard of the un-tiability of such knots is the [i]bowline[/i] - when we evaluate an eyeknot regarding its un-tiability, we should compare it to the bowline - the comparison to the [i]fig-8 eyeknot[/i] should be limited to [i]security[/i], IMO.Perhaps you should consider the Beal reference URL you sent, and the inclusion in its rope data --which has a remarkable consistency to it per rope diameter(!)-- of two knots : viz., [i]fig.8 & fig.9 (eyeknots)[/i]. Their inclusion is because they are state-of-the-practice, standard knots. And in looking to that, I so devised the [i]"Lehman8"[/i] as being an easier-to-untie like knot. The [i]bowline[/i] is not unknown, but in many such user-areas, unchosen; the knots Beal gives are commonly iused.
–dl*
I do not WANT to describe my own “trials” - because such “trials” ( like the ones performed by mobius, for example ), which are nothing but incompletely and/or wrongly and falsely performed tests, do not tell ( and do not prove, of course ) any-thing about knots ! At most, they only provide incomplete and/or wrong / false indications/hints, which can be “explained” in any way one wishes ! They can easily be misleading, and conceal, unintentionally or intentionally, rather than reveal, the shortcomings of knots. Do I have to “describe” how I know that the Zeppelin bend is a much more easy to untie knot, after even moderate loading, than the so-called “Zeppelin loop” - as mobius, who performed such “trials”, claims ? And even if I “describe” one comparative “trial” of those two knots, on a 3mm line, under a 100kg load, with any result whatsoever, would this tell or prove anything ? Or would it only enhance any erroneous prejudices/beliefs one may have about those two knots, and so feed one more knot myth ? On the other hand, would it be difficult for anybody who would wish to cast doubts or even ridicule and dismiss beforehand those “trials”, to do it ?
Noope - I am afraid I happen to have higher standards about what a scientific experiment, a “test”, is, or should be ! Especially a test which involves complex phenomena, in this demanding field of material science (1).
If I were able to perform scientifically sound tests, I would first had tested some knots tied by myself, which, IMHO, are interesting, or even good - and not the worst knots tied by Dan Lehman, which, IMHO, are mediocre, at best ! Myself, I do not expect anybody else to test the knots I happen to tie - especially if this “else” does not bother to say a f.. word on 99% of them ( and, for the remaining 1%, he only boasts that he, too, had tied them, long before me ).
So, yes, I would nt “bother” to describe “trials” on mediocre knots, which are not tried even by the knot tyers who had tied them in the first place !
So, you are telling that the fact that the Lehman8 eyeknot can be untied easily after it is tied on 3mm cord, and it is tensioned by 100kg, proves that it can also be untied easily after it will be tied on a 9-12.5 mm rope, and it will be tensioned by, say, 1400 kg… ( because that ( 9-12.5 mm) is the size used in climbing and rescue, which are the applications the Lehman8 was supposed to be designed for…)
OK. Tell it to Beal, to include your suggestion in its brochures .
The state-of-practice, standard knots are NOT meant to also represent the standards regarding the easiness of their untiability ! “I” know that the fig.8 and the fig.9 knots are commonly used ( although “you” do not know that I know it… ) - but that DOES NOT mean that they are used because they are easy to untie ! This DOES NOT mean that they set the standards of easily untied knots ! The fact that the bowline is un-chosen, DOES NOT mean that it is un-chosen because it is difficult to untie !
Rather than engage gratuitous derision,
one should have better sensed the clue
to a problem/mistake, and made a query
more on the tone of my …
As for any difficulty untying the zeppelin end-2-end knot, I'd want to see the jammed structure : had it capsized (as can the bowline)? For it, also #1408, should be easily loosened in most cases...., as I am now apprised of the surprising (IMO for Mobius) but otherwise seen in various places mistaken knot masquerading at the [i]zeppelin[/i] --that more-like-[i]SmitHunter's[/i]-structure.
Mobius, you should examine your Slide#3 in which
you show both zeppelins --eye & end-2-end-- and quickly
see the difference! (I recall going some several rounds
w/someonElse over the supposed jamming of Ashley’s
bend #1452 until realizing that he’d mis-dressed it
into a jamming version.
–dl*
Thank you for this feedback Dan. Indeed, I have made a mistake tying the Zeppelin Bend in the Slide#3 you refer to and I show again below. I think what happened was that I swapped the ends of the ‘q’ around and the tail was the horizontal rather than the vertical crossing. I thought the ‘b’ ‘q’ method of tying the Zeppelin was easy… not so for me it seems, when I have not practiced it enough. Perhaps I am not totally alone in this.
Whatever the case, the trials that I conducted with the ‘False’ Zeppelin Bend did not indicate it as a particularly good bend. I have recently upgraded my test rig and will redo the Zeppelin Bend in both 3mm Poly Braid and now 6mm PE/PP material and see what transpires. I will share the results with you all, probably in a new thread.
I am glad I usually go to the trouble of photographing the knots I trial (for verification). I commend Dan for seeing my mistake, I had looked at the image below a number of times and just not seen the discrepancy. I have fallen victim to an “evil impostor”, my apologies to all.
Cheers.
mobius.
Your b&d bend seems secure, so it’s more of a benign impostor. Its jamming is inconvenient, but not much of a hazard. With more use of the Zeppelin Bend, I’m sure you’ll get used to verifying the correct outcome with a quick check of both sides.
Only people that had never understood what the genuine Zeppelin knot, the Zeppelin bend, is, and how it works, make “a quick check of both sides”(sic) :).
The Zeppelin bend is nothing but a rope-made hinge - and there are no hinges where the leafs themselves are hooked to each other !
Only someone still unclear on the subject of discussion
(how to discuss, i.e.) will continue to harp on this old
sorry tune so much as to miss the fact that insofar as
the z. has any “hinge” so too has this “imposter”
–there is no "hook"ing of any “leafs” to each other
(though that too might be hinge-worthy,
and in better knots, is what is done 
).
–dl*
I am really sorry to notice that more and more you understand less and less than I suppose you can and you will …
My remark was, obviously ( for me, at least ), about the difference between the Zeppelin and the Hunter s bend, the difference regarding the “b&q ness” Mobious was talking about and roo commented on.
( I have also to inform you that I happen to “see” some, at least, “old” knots ( including the Zeppelin bend ), more clear than you can even imagine you will ever do - and that is why I manage to tie some “new” ones - while you are occupied with more important things : the noble duty to always defend roo and go after me when you think you can, like in this silly case - because you would nt dare to say anything about my knots, of course ! No, continue roo s strategy, “do not feed the troll”(me), keep silent : eventually they may be forgotten ! ) )
Rather, “presuming to notice …”.
... you understand less and less than I suppose you can and you will ... My remark was, obviously ( for me, at least ),Moi, aussi.
about the difference between the [i]Zeppelin[/i] and the [i]Hunter's bend[/i], the difference regarding the "b&q ness" Mobious was talking about and roo commented on.No, the difference that they remarked at --to the point of comparing "side"s to see that they look the same-- is that between the [i]zeppelin[/i] & the knot M. presented (which only *resembles* [i]SmitHunter's bend[/i] --i.p., it does NOT interlock [i]overhands[/i] by "hook"ing "leafs"; but it does do everything [i]else[/i] of the [i]z.[/i]!)
( I have also to inform you that I happen to "see" some, at least, "old" knots ( including the [i]Zeppelin bend[/i] ), more clear than you can even imagine you will ever do --and that is why I manage to tie some "new" ones--I say that your premise is hardly certain, and your conclusion ("... which is why ...") a partial non sequitur : by not seeing ... clearly, one might well find oneself tying "new" ("unintended", but ...) knots a-plenty! (One of my jokes re How To ... : "just come up with a complicated knot, and in trying to re-tie it no doubt you'll go astray and end up with a *new knot* !") ;D
the noble duty to always defend roo and go after me when you think you can, like in this silly caseI think that we can see who's "going after" whom all too clearly. The silly case of repeatedly telling the world who sees what how and why not and !
(Now, we’ll pause to see if you can find a “hinge” just
like that infamous one lurking in the z. in the case
where the hinged elements simply have a different
relation to each other --one, in fact, much more like
the hardware hinges I see (i.e., b & p, not q) !
–or, if you only see that Roo made a post that you
haven’t attacked)
- because you would nt dare to say anything about my knots, ... : eventually they may be forgotten ! :) :) :) ) )And I'll have to remind you that **I** have PILES of "play ropes" tied up (literally) with my *own* (new) knots, to which I've given scant time & attention (i.e., I've not put ink to paper; I've not "publish"ed, as you exhort me to do); your knots sit in good company, in this sense. And it is all a bit overwhelming to get control of. (So often, an effort to record [u]this[/u] knot results not in that, but in then producing --in tied-up, hard-now-to-find play rope-- yet another *new* knot in need ... ! >:( )
BUT, I think that I will get time to do a chunk of some
such recording. (The benefit to delay is the chance, then,
to group knots per structure --older & newer.) ((Another
benefit is that, given the delay and press of work to do,
one is more willing to discard knots, so maybe some more
chaff is tossed out.))
At last, something on which we agree !
AHA ! THIS is why you do not tie ANY knot ! You see crystal-clearly ! And I was wandering…
This STUPID theory, that an ape can write what Shakespeare did, and a knot-troll ( like me ) may happen to tie some good knots, was, coincidentally, promoted in this Forum in the past, by guess whom ! ( However, I am not surprized by THIS coincidence…)
So, I had tied all the “new” knots I did, because I tie “random knots”, and, every some Xillion years, one of them happens to be good. OK. Now, tell me, Is THAT the best explanation you had managed to pull out of your sheave ? Perhaps it is time to start ( tying and ) trying more, again…
However, yes, indeed, it may happen : Mobius - who admits he could nt see the difference between a Zeppelin and a Hunter s bend ( and THAT was where I was referring to, your brightness ) - had tied the most beautiful Mobius loop, which generations of knot tyers had missed !
I can only hope that you will, because I know something you do not : that you, too, you are not immortal.