I prefer to focus on the knot and describing the loading as offset. If I were to test a loop knot for offset loading, there might not be a loop (let alone a ring) to be found.
I totally agree DDK, the knot is not aware of what the cordage is doing beyond a cm from its entry point, it only knows the force and directional vectors as they enter the knot. Whether the cord is attached to a loop, or an anchor a kilometer away is of no interest to the knot, so we should disregard how the cord obtained its force and directional vectors and concentrate only on how they affect the knot.
Mark, I totally applaud your right to hold a view different from mine ([b]and from the majority of other posters[/b]) - indeed, sometimes [b]the lone voice[/b] can even be right...And here I see (again) the use of language that is completely unnecessary.
the majority of opinions posted are at odds with the opinion you are offering for discussionHmmm - social proof again. Derek, there is a very small audience (in comparison to the entire world). And some of this very small 'audience' have been warned by the moderator to desist from personal attacks. The English language is complex and it is possible that the word 'ring' is understood and conceptualized in different ways. To be clear - I understand the word 'ring' to be a thing of circular or round shape. Eg a ring that is worn on a finger, a circus ring, the symbols of the Olympic games - in my view, are all circular in shape.
I also note that the concept of change can evoke strong feelings in some individuals - and in some cases, trigger outrage. Clinging to terms published by Ashley (published some 75 years ago) may not be as relevant today as is was then. Some concepts were assumed or implied - probably because of deep tradition.
For me, I embrace change and do not fear it.
And for me, if a person says; “Heh, ring load that eye knot”
My response would be - “Can you be more specific please?”
“In which direction would you like me to ‘ring’ load that eye?”
However, as I have previously stated, I find no problem with you holding a [b]lone [/b]opinion, as sometimes the [b]lone [/b]voice is the only one seeing the truth for what it is.I had to chuckle at your use of certain language (again).
Actually, while pondering my assigned ‘lone’ status - I might post a quiz for you - with images of various loading profiles on the eye of a fixed eye knot. You would have the (lone) option of providing answers.
However, it is my hope that you will be able to focus on the issue here as per your original post, of Ring Loading, and can perhaps put to one side what we each personally choose to call a [b]loop[/b]Actually, the concept of an eye is pertinent to the broader understanding of how it (the fixed eye) can be loaded. The eye of a fixed eye knot has no particular chirality. So when I am load testing (a fixed eye) I wont have to repeat the tests for an 'S' chirality eye and then a 'Z' chirality eye (because it doesn't exist). I could load the fixed eye in a [i]transverse [/i]direction - so that the SParts are isolated from load - and the legs of the eye are loaded in opposition (although this is not quite 'offset' loading as would occur with a 'bend'). Or, I could apply a [i]circumferential [/i]load - to expand the eye in multiple directions simultaneously. In this case, the SParts are not completely isolated from load. If I load the eye [i]axially [/i](longitudinally with respect to the SPart) - the SPart is maximally loaded - and both legs of the eye are subjected to 50% of the load in parallel.
I do not believe that we are discussing the purpose of the IGKT. However, as one of the founders who pushed for the creation of this discussion board, I remain fully cognisant of its purpose, which I am certain we will all keep in mind.No - you misunderstood my point - although I could have worded this better. I meant [i]this [/i]IGKT forum - this very section of the forum - where people can engage in technical/theoretical discussion. Although I have found (from past experience) that you sometimes have difficulty in remaining polite and avoiding thinly veiled comments that are intended to devalue or denigrate opposing views.
Part of my underlying reason for wanting to commence discussion (apart from the high probability that the term ‘ring’ loading was originated in this forum or via certain individuals inhabiting the IGKT forum) - was due to the ‘Mobius Butterfly’.
This derivative of #1053 Butterfly has some very interesting properties and is also ‘TIB’.
It appears that this particular fixed eye knot can be loaded in a number of different directions with impunity.
…
One thing I really like about this IGKT forum is that the moderators are quick to call out bad behaviour (unlike in other social forums). There is guardian angel watching over this topic thread..
Typos corrected…
Mark, I refuse to be drawn into a sensless heated argument with you by your use of implied threats.
To draw this discussion back to the issue at hand, I will reiterate my previously stated ten points. If you have any arguments or perspectives that might be useful to help me consider an alternative opinion, then I would appreciate reading them, but I do not wish to see any further off topic innuendo, or implied threats of divine retribution.
- Ring loading is a simple and well understood term which has a single variable aspect.
- There are not ‘classes’ of Ring Loading, but there are degrees of Ring Loading.
- Fixed Loop knots are cordage Force Machines which transpose and translate forces between the loop legs and the primary load bearing SP.
- Ring Loading is defined by the angle subtended by the two loop legs.
- When the loop legs are parallel, the subtended angle is zero and there is no, ie. 0% Ring Loading.
- When the loop legs are diametrically opposite, the subtended angle is 180 degrees and the knot is experiencing 100%, i.e. fully Ring Loaded.
- When the loop legs subtend and angle of 120 degrees, both loop legs and the SP are potentially subjected to equal tension loads.
- At subtended angles above 120 degrees, the forces required in the loop legs needed to balance the SP load, rise exponentially to multiples of the applied SP load.
- All knots respond to applied forces, some are capable of resisting change, while some are liable to capsize. By way of example, THE Bowline is reasonably stable to low levels of Ring Loading ( ca 20 degrees and less), but is at high risk of failure at high levels, while other knots such as the Carrick Loop retain their stable structure.
- All loop knots can experience Ring Loading (an angle subtended by the loop legs). To factor this into our knot usage, we need to be cognisant of the impact of divergent force vectors and be familiar with the response our knot structures have to applied loads.
Derek
Gentlemen, we are getting repetitive and basically going nowhere.
Terminology has been a bane of this society for a long time and I?m not sure that a consensus is forthcoming.
I personally feel that more distinct descriptors can help with the describing and defining of a fixed eyeloopring that is loaded.
One can describe how the loading(s) can and will effect the core and what may happen during loads that are not evenly applied either slowly or with sudden jerks.
We must remember that quite a few members that come here are not knot efficienados and can learn what the common parlance means via pleasant discourse.
So, please notch it back a bit and help others to understand better as we travel this path.
SS369
Mark, I refuse to be drawn into a sensless heated argument with you by your use of implied threats.I didn't know that I was engaging in a "senseless" heated argument! I'm simply responding to your posts. And I didn't know about the implied threats?
I have attached an image - which again is simply showing various loading profiles on the eye of a fixed eye knot.
The eye is non slipping (ie it is not a noose).
I have chosen the Mobius Butterfly - but I could have chose an alternative knot - eg #1047 F8.
Origin of the term ‘ring’ loading:
In my view, the term ring loading originated in the IGKT forum.
Going through various knot books - I cannot find specific references to ‘ring’ loading with clear and distinct definitions.
It is not present in Ashleys book and CL Day (Art of knotting and splicing).
Harry Asher also did not mention the term or provide examples.
Cant find any examples of ring loading in Budworths books…
I will keep looking - but my hopes are fading.
So where did the term ‘ring’ loading originate?
Highly probable that it was from the IGKT forum - and likely from one or 2 individuals.
Is ‘ring’ loading commonly understood by every person (or everyone)?
Depends on what you mean by ‘everyone’.
There is a very short list of persons who allegedly understand the term - they represent less than 0.000000000001 % of the Earths population.
What is the definition of a ‘ring’?
The ordinary dictionary meaning is an object that is round or circular.
What happens if you ask an ordinary person to ‘ring’ load the eye of a fixed eye knot?
They will likely be confused for a while - and ponder which direction to pull.
Some are likely to pull outwardly in all directions (or make an attempt to do so).
Some might pull sideways.
Some might pull lengthways.
In the beginning:
It was the Mobius Butterfly that intrigued me.
It seems that the eye can be loaded in multiple directions with relative impunity.
So I began to ponder the different directions of loading - and tried to assign meaningful descriptors for the various directions.
The attached image:
Image A = represents axial (or longitudinal) loading
Image B = represents circumferential loading (and the term ‘ring’ loading might reasonably apply)
Image C = represents transverse (radial or cross-load) loading
In ‘A’ - the SPart(s) is under load (equal and opposite to the tip of the eye)
In ‘B’ - the SPart(s) only experience partial loading or, might have zero loading depending on how the eye is oriented
In ‘C’ - the SPart(s) are isolated from load.
…
Now Derek, you may not like what I have typed.
And thats fine - you dont have to ‘like’ my typed words!
You can hold an opposing view - and you could assign different descriptors for the various loading directions.
You may choose to conceptualize A, B and C as all being various degrees of ‘ring’ loading.
In holding your views - and advancing them in opposition to mine - there is no need to use phrases such as:
Ring loading is a simple and well understood term
the lone view
the lone opinion and lone voiceRather, you could simply state that image B (in your view) represent a degree of ring loading just as image C is also a degree of ring loading.
I concur with the moderator in that the layperson likely wouldn’t have a clue about these concepts…
Although some might have a clue - and apply the ordinary dictionary meaning of the term ‘ring’ - which is a circle/round object - and perhaps consider image B as being ‘ring’ loading?
EDIT:
An interesting analog is the various loading profiles on a carabiner (irrespective of its possible attachment to a supporting rope - which could be thought of as the ‘SPart’).
Roping technicians and other roped sports user groups describe the direction of load on a carabiner using specific terminology.
The term ‘ring’ loading is not used to describe any of the loading directions in the below image.
If load is aligned along the spine (or major axis) of the carabiner - this is generally described as ‘major axis’ loading.
Loading in four (4) different directions on a carabiner (per link below) the term ‘quad’ loading was used.
Presumably if 8 or more different directions were configured - the tester might have used the term circumferential loading?
Interesting link where the tester has tried to describe the various loading directions on a carabiner:
https://www.blackdiamondequipment.com/en/qc-lab-off-axis-tri-axial-carabiner-loading.html
Hi Scott, thanks for the intervention and as ever your sage direction. As you will have seen, I had already decided to disengage from dialogue with Mark until such time as he decides to come back to the post with constructive discussion.
However, I picked up from your post an issue that may be at the very heart of this disagreement. The issue is that you suggest we study further the ways in which the loop can be loaded. This made me realise where both yourself and Mark have a misunderstanding of just what ‘Ring Loading’ is.
I will digress slightly in order to explain the point.
If we test rope for its breaking strain, then we put a piece under increasing load until it fails. - it doesn’t matter to the rope under test where that load came from or what created it - the rope only cares about the load it is experiencing. Consider this as I now move back to ‘Ring Loading’.
When we talk about ‘Ring Loading’ we are referring to the impact upon the knot of the forces being applied to it by the loop legs and the direction of those forces. These are vectors of load and direction. As there are only two legs, the direction can either be parallel or at some angle to one another.
But the key issue is that it is the forces and angles at the knot which are relevant. Just like the rope example above, it does not matter how those forces and angles originated, only their magnitude and the impact they will have on the functioning of the knot.
If the legs each enter the knot with (for example) 100lb load and an angle of say 120 degrees, then there are an infinite number of possible ways the loop could have been loaded to achieve those parameters, but how they originated matters nothing to the knot in how it responds to the ring loading of 200lb at 120 degrees.
So you see all this talk of loops loaded by dozens of children or multiple binas and multiple literary designations for forms of loop loading are irrelevant, The only aspect that defines the impact of the final loading on the performance of the knot are the vectors of force and the angle between them. Instead of detailing how those forces arise, perhaps we would be more constructive at considering how ring loading can lead to knot failure.
Derek
My previous post was certainly a contribution to this topic thread - and all the information was posted in good faith.
I feel that I must reply to some of what you have posted - because you are painting me in a negative light.
All of my words are in direct reply to Derek’s allegations.
I am not intending to be belligerent or scathing… I am simply replying to Derek’s words.
disengage from dialogue with Mark until such time as he decides to come back to the post with [i][b]constructive discussion[/b][/i].? I find it very interesting as to how you arrive at these conclusions. You are cleverly painting me as the villain. You should go back and re-read your posts from a non biased viewpoint (which admittedly would be hard to do). Consider your choice of language? (I am alone, I am the lone voice, basically my entire conceptual framework is false...). You are coming into this discussion not from a friendly contributing point of view - but rather as a competitor. Derek, if a person does not agree with your conceptual framework - do you automatically regard them as 'wrong' and that you must devalue their viewpoint?
Its amazing that this topic thread can evoke such a strong emotionally charged response from you Derek.
All I am doing is discussing the term ‘ring’ loading.
I am trying to provide discussion along with supporting images to build a conceptual framework.
Now - you may not like it Derek - and that fine, you are not ‘forced’ to like or agree with anything.
The manner in which you choose to respond reveals much about your underlying intent.
[i][b]yourself and Mark[/b][/i] have a [i][b]misunderstanding [/b][/i]of just what 'Ring Loading' is!! Seriously Derek? There is no 'misunderstanding'. The 'misunderstanding' possibly lies with yourself in that you appear to misunderstand what the intent of this thread topic is. All I have stated is that the term 'ring loading' is vague - and isn't well defined. In stating this - it doesn't mean that I have a knowledge deficit, lack of professionalism, a lone view, or lack the ability to grasp loading profiles on the eye of a fixed eye knot. Also, it is a stretch to also assume that the moderator also lacks understanding! I am simply stating that the term 'ring' loading could be improved - and perhaps more descriptive terminology could be used. There are more descriptive language choices...
an issue that may be at the very [i][b]heart of this disagreement[/b][/i]t? With all due respect, I think you are confused. There is no 'disagreement' in the negative sense of the word. Its just a discussion. And even if there is alleged "disagreement" - is that by itself bad or wrong? Not everyone agrees on all concepts - and that's fine. But thats not a reason for the underlying tone behind of all of your posts. Take for example your preferred use of the term 'loop' - perhaps because you feel strongly bound by tradition and fear going against centuries of that tradition? I choose to use the term 'eye' - which (in my view) actually is a more appropriate fit within the broader scope of knot theory (eg chiral nature of loops). At every opportunity, you attempt to insert and override the term 'eye' with 'loop' - which I find amusing :)
When [b]we [/b]talk about 'Ring Loading' [b]we [/b]are referring to the impact upon the knot of the forces being applied to it by the loop legs and the direction of those forces.? The use of the word "we" is very interesting to me. I thought that it was 'I'' that started this thread topic in good faith. In joining in on the discussion - from what underlying intent and purpose are you coming from? In your mind - do you see me as a 'wrong doer' perhaps? Its just a discussion - and I wanted to elicit informed discussion about the various loading profiles on the eye of a fixed eye knot.
So you see [b]all this talk[/b] of loops loaded by dozens of children or multiple binas and multiple literary designations for forms of loop loading are [b]irrelevant[/b]? Your use of the word "irrelevant" is very interesting to me. It is effectively an attempt to devalue my contributions. Why do you choose to use such language?
[b]Instead [/b]of detailing how those forces arise, perhaps [b]we [/b]would be [b]more constructive[/b] at considering how ring loading can lead to knot failure.? And here is the word "we" again. It appears that you already have all the [correct] answers - and wish to insert your viewpoint at the exclusion of mine? Its just a discussion - its not a competition of who has the greater knowledge. The idea is to elicit informed discussion - and not to devalue another person viewpoint. There is no need for an adversarial approach.
…
Summary:
Wow.
Your choice of language here reveals much about you Derek.
Who would have thought that the term ‘ring loading’ and my attempts to elicit informed discussion about it could evoke such strong reactions?
In my replies to you, I am careful not to describe you as a lone voice, or alone in your conceptualization, or being irrelevant, being threatening, not making constructive contributions, the list goes on!
Is it because I have written many technical papers and other learning documents - that you see me as an adversary?
To the moderators:
I am making a formal request to have this entire topic thread deleted.
It is regrettable but, I don’t think this forum is ready to discuss the term ‘ring loading’ in an informed, non belligerent, and non adversarial manner.
Some contributors see this as an adversarial topic thread - instead of making contributions of a positive character, it has taken on the tone of a competition.
For these reasons, I don’t think anything useful or constructive will ever evolve from this topic thread - and it should be deleted in its entirety (including all associated images).
Plea to the Mods.
I note with some concern that one of the contributors has requested the deletion of this entire thread.
I personally have found the whole discussion most stimulating, driving me to consider more thoroughly what it is that we almost glibly refer to as ‘Ring Loading’. I have found the topic to be of significant value to the our field and therefore respectfully request that this thread not be considered for deletion.
Derek
In the hope that we are allowed to continue with this post, may I suggest that we continue the exploration into why some knots are definitely not ring stable and why some are.
Could we start by building up two lists - 1. those known to be exceptionally ring stable and 2. those known to be disastrously unstable. If I might kick this up the road with:-
List 1. Experienced to be stable - The Carrick Loop
List 2. Known to be unstable - The Bowline #1010
Derek
Edit: Typo correction
Hi Derek
I am curious as to which form of the carrick eyeknot, you refer to as being ring stable?
Link : https://igkt.net/sm/index.php?topic=6257.msg42156#msg42156
I am asking this, because if you mean the previous profile tested and depicted by agent_smith, then my impression is that if subjected to ring loading, it will capsize to a crossing knot based final energy state, (stable but different), therefore, i wouldn’t consider it as the best choice for ring loading stabillity.
In my view, a rock solid ring loading profile would constrain the original knot from capsized forms, or from nub deforming issues. I’d certainly add all the tugboat-like knots, in the second list like Anglers or flying bowline eyeknots.
Ring or cross loading concept, IMO, is crucial and directly related with the midline concept. The development of a TIB end of line eyeknot with a solid ring loading profile, most likely is associated with a decent midline profile, like alpine butterfly or EHL.
Hi tsik,
I view #1033 as a hybrid between the Carrick and the Myrtle. The Myrtle is two enmeshed nipping loop components while the Carrick is two enmeshed carrick components. As the hybrid, #1033 enjoys one component from each parent. Personally, I do not like #1033 at all because the nipping loop component interferes with what for me is the most important characteristic of the Carrick, that being, its self dressing ability. Tie it, load it, and it dresses itself into two perfectly interlocked carrick components. So, no, I am not offering up #1033, but the loop knot derived from #1439 (of course, neither of the images Mark Gommers presents in the post you referenced are Carrick’s, rather, they are a form of tying mnemonic to remember their crossings, the working knots themselves do not form until working load is applied).
But you bring up an aspect of Ring Load stability that I had not considered :-
In my view, a rock solid ring loading profile would constrain the original knot from capsized forms, or from nub deforming issues. I'd certainly add all the tugboat-like knots, in the second list like Angler's or flying bowline.By contrast, I see all knots as flexible constructions capable of and liable to transformation under load, and this for me is one of the joys of the Carrick - subject it to load and it dresses itself to optimally handle that load. This is true even when the loading changes after the initial dressing. So if you load the Carrick loop knot with zero ring load, it will take up one form of twin interlocked carrick components, but change the loading to 100% ring loading and the knot transforms int two different carrick components, now ideally structured to process the load.
Clearly both perspectives are valid, so any consideration of Ring Loading must allow for both the ‘Rock Solid’ response as well as the ‘Safe Reactive’ response.
‘Rock Solid’ speaks for itself - it retains its structure irrespective of the degree of Ring Loading, while ‘Reactive’ will also include all those knots which react disastrously to high Ring Loading, so I understand your reticence to consider any reactive knots as being stable under Ring Load, but I hope that you are able to accommodate the Carrick loopknot into the category of knots being Ring Load stable.
Or perhaps, for clarity we might need two categories - Ring Load Stable and Ring Load Safe. Plus of course, the category that is neither stable nor safe - step forward #1010
Derek
How so?
What CAN be suggested are ways in which an
EYE KNOT’s ends (parts leaving the nub) are loaded
–i.e., a matter of angles of eye legs, for the common
notion of “eye knot” ; whereas for my mused notion
in which we see only the knot “nub” and all ends
leave our view giving only an ANGLE and not any
particular connection to each other (so, maybe no
actual “eye” in this “eye knot”!),
it would be conceivable for the eye legs to have
different loads (such an “eye knot” as tying into
an arborists lowered-for-getting-some-gear line
with a lanyard attached to this gear, and the knot
looking just like a BWL (even though the two
would-be “eye” legs are of different ropes, say).
In the case of the use of the translated-from-German-to-English
term “ring-loading”, it is simpler : the knot is loaded qua ends joint
of eye leg to eye leg, aligned & opposed on a single axis.
Mark has come and grabbed someone’s expression
and decided that HE must set the world right by
redefining the expression, which 'til now
(and w/o bothering in this discussion, beyond now)
they have used with adequate understanding.
Should the term get revised, to accommodate some
better matching of some language’s notion of a “ring”? (no)
–or upon some revelation of actual physical variations
worthy of individual naming & articulation?! (maybe?!)
I can see a concern with a loading that is a hybrid
of the understood “ring-loading” and normal loading
in which the SPart and one eye leg are generally
opposed to the other eye leg (so, ring-loading and
then as the belayer using the eye qua belay loop/“ring”
is jerked away from the anchor until the eye knot’s
SPart then is also loaded.
But all this is still a matter of angles of loaded parts
into the knot --in the just-above case it is mused
that one eye has been drawn back beyond a right-angle
difference to normal while the other is roughly normal,
and the SPart makes this possible by holding the knot
generally in the original orientation.
So you see all this talk of loops loaded by dozens of children or multiple binas and multiple literary designations for forms of loop loading are irrelevant : the only aspect that defines the impact of the final loading on the performance of the knot are the vectors of force and the angle(s) between them.Yes, but to a different discussion, as I note above (where e.g. ring-loading might be mixed with some contribution to the forces at the knot from the SPart --a hybrid of ring- & canonical-loading for the eye knot). Or, unless, what might evolve to be (called) a hybrid of "cross-loading" & "normal-loading".
As “offset” has a now growingly accepted (we should hope)
sense of the knot being entirely to one side of the axis of
tension/loading, it is not accurate to describe the loading(s)
of concern in this discussion, except for such eye knots as
the (common to this topic’s source!) fig.8 & overhand
eye knots. But that is a coincidence of the form of
the knot, not a given consequence in general on the
aspect of loading an eye knot’s eye. E.g., ring-loading
a #1010 BWL is dangereoius as it might spill the knot,
as it converts it to the inferior-form Lapp bend; but for
a Fig.8 eye knot. it’s bad because it’s an offset loading
which might cause the knot to capsize.
–dl*
[b]of course[/b], [i]neither [/i]of the images Mark Gommers presents in the post you referenced [i]are Carrick's,[/i]? What an odd comment to post in this forum. Of course - it actually goes without saying that the images are what I refer to as 'dressing states'. Clearly and obviously load has not been applied and so the photographed structures have not undergone transformation into the final energy stable state. I photographed them in their pre-transformation dressing state so it would be easier for viewers/readers to see the geometric differences between #1003 Carrick loop and #1439 derived Carrick eye knot.
…
To re-emphasize (again) that I had originally started this topic thread to find better terminology to describe the various loading profiles that could be applied to the eye of a fixed (non slipping) eye knot. Sort of like settling on the term ‘eye’ to describe the round connective interface of knots such as #1047 F8 and #1010 simple Bowline (leaving ‘loop’ to a more stricter character which has a chiral form).
Background
I started thinking about the IGKT forum originated term ‘ring loading’ and how a layperson might interpret it.
I even thought about a more experienced knot tyer - and how such a person would react if asked to demonstrate ‘ring’ loading on the eye of a knot.
It occurred to me that a person might pause and consider exactly which direction to load the eye.
I thought perhaps some might take the literal meaning of the word ‘ring’ - and attempt to expand the eye outwards in multiple directions (ie circumferential loading).
The Mobius Butterfly
The Mobius Butterfly intrigued me - because it appears to be stable in a number of different loading profiles.
I though of trying to add a modifier to the term ‘ring’ loading - eg ring load that eye in the axial direction or ring load that eye in a transverse direction.
But the term ‘ring’ troubled me - because of its ordinary dictionary meaning - which is a circular or round object.
In a literal sense, ring loading is ‘circumferential’ loading.
By applying my descriptive terms - I thought perhaps the term ‘ring’ could be deleted - and instead, axial/transverse/circumferential inserted - which would provide a definite directional reference frame (with respect to the SParts).
Refer photos below - comparison between #1047 F8 and the Mobius Butterfly.
I had earlier thought to use the term 'cross-loading (in the radial direction) to describe transverse loading.
Cross-loading is a well understood term for side-ways loading across the gate of a carabiner.
Why not?
Is there a real problem with diving into more apt or better descriptors?
Perhaps there are people out there that would care to read a bit more, maybe want technical descriptions.
There is validity in including the effect on the core of the sample, sure, but just to say ?ring? loaded is insufficient, imo.
Yes, I would agree that some of the knottyers out there do recognize the term, but that shouldn?t inhibit further conversation.
So, instead of just basically dismissing Mark?s desire to discuss this, maybe add to the discussion.
SS
The belay loop in an alpine harness is a happily performing ring-loadable loop. A layman can trust that clipping into the belay loop with any number of biners will not cross load it. The belay loop is trusted for it?s un-breakability in a wide range of uses (catching a lead fall, rapelling, hanging backpack while rapelling). Beyond these, I doubt the layman has any other sense of what ring-loadability should be. Why should he/she expect more? The belay loop is a great soft textile ring.
It is clear and well understood that under the frame of ring loading, we refer to knot structures that have reached some final energy stable state, after load has been applied to their initial dressing states.
It is also good to know, which knot corresponds to your favourite Carrick structure #1439 derived (questionigly, from our very first interactions, but the mystery is finally solved). Having enmeshed carrick components before (aka crossing knots), i’ve come to prize the quality of such knots.
By contrast, I see all knots as flexible constructions capable of and liable to transformation under load,
We might have a clue to where they’re going, but can we really predict their response beyond a certain degree of loading?
but change the loading to 100% ring loading
How is this 100% ring loading defined? Has anything to do with knot failure? Is there anyone who has seriously ring loaded a knot and share his/her findings?
but I hope that you are able to accommodate the Carrick loopknot into the category of knots being Ring Load stable.
I am not really sure about the rock solid ring loading stability. Alan Lee has reported serious deformation, induced by the carrick components, after heavy axial loading. It superficially appears that it can process normal transverse loading but if that exceeds some critical levels, i estimate that ring loading distortion might not be avoided.
I do not like #1033 at all
I wouldn’t be so negative about #1033 (the hybrid :)). It features all of the aforementioned properties, like self dressing ability, stable final energy states or jam resistance, plus one more. It is conceptually simpler.
Hi tsic, in my opening post I offered my personal definition of RL for consideration and critique.
I felt that parallel loop legs offered no RL to the knot, i.e 0 degrees between them gives zero RL. But at the other end of the RL spectrum, if the loaded loop legs are in opposition, i.e. 180 degrees apart, then the RL is at its maximum (or 100%).
Of course, to achieve 100% RL, there must be no loading present on the SP (see parallelogram of forces), and indeed, if the loop legs are already heavily loaded and at 100% RL, then even small forces applied by the SP are amplified massively and are capable of driving the loop leg load into the knot well above rupture forces.
Re work already published on the consequence of RL: I think the prime value of Mark Gommers’ creation of this post is that it highlights two facts - 1. that we all take RL as an issue to aware be of, and 2. That there is clearly a lot we need to study about this important aspect of our knots and their usage. For that I owe Mark a Thank You.
It promises to be a rich field.
Derek
Edit spelling.
But, we should note, not for taking a lead fall
–i.e., harness makers always (?) state that one
should reeve the climbing rope through the harness,
not to tie to the belay loop, beefy though it is.
(Sadly, famous climber Todd Skinner apparently
had so worn out his harness’s loop that it broke
under body weight while he was rappelling.)
Hmmm, & wow, here’s some rather disturbing information
about belay loops --the bit of not looking bad:
Belay Loops. Every harness that had a belay loop was tested. Belay-loop strength ranged from 2,160 pounds to well over 8,818 pounds. Eight belay loops failed below 3,306 pounds. Six of these had been listed as useable in a pinch or by friends. [b]Only one harness showed [u]any visible signs of damage[/u] to the belay loop[/b].Curiously, 23 belay loops of the same make and age from one source
showed a range of strength values, with the highest breaking strength
being 41 percent greater than the weakest. Another belay loop used
on a variety of harness models returned from a variety of sources had
a range from 3,527 pounds to 7,054 pounds. Clearly, quality control for
some harnesses is lacking, but whether this is rampant throughout the
industry is unknown.
The average strength of all of the tested belay loops was 6,040 pounds.
Source: