Author Topic: Ring loading is ill-defined (vague)  (Read 1279 times)

agent_smith

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Re: Ring loading is ill-defined (vague)
« Reply #15 on: August 26, 2020, 12:13:37 AM »
Quote
I cannot at this time picture a scenario that uses the circumferential loading profile fully.
Some vertical rescue teams have used the eye of #1053 Butterfly as an improvised 'rigging plate'.

Some complex 3D rigging scenarios use whats known as a "floating rigging plate".

A #1053 derived Butterfly (mobius variant) would be suitable for such an application.
Previously, a regular #1053 Butterfly has been employed.

I think the derived Mobius Butterfly would be a better choice for employment as a 'floating rigging plate'.
Note: I'm using the term 'Mobius Butterfly' on account of Xarax stating that IGKT member 'Mobius' first presented it.

Anyhow, this would be the closest example of a circumferential loading profile.

And thank you for steering this topic back on course.
My original contention is that the term 'ring loading' is not well defined - as it does not specify the direction of force.
It is largely left to the imagination of others to choose a loading direction.
Historically, 'ring loading' was likely 'assumed' to have been longitudinal cross-loading of a fixed eye. All I am trying to do is define the various directions of loading - so it does not have to be 'assumed'.

SS369

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Re: Ring loading is ill-defined (vague)
« Reply #16 on: August 26, 2020, 12:43:42 AM »
Thanks Mark.

I had thought about a multiple clipping in scenario, but that didn't quite fulfill my thoughts.
 

Dan_Lehman

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Re: Ring loading is ill-defined (vague)
« Reply #17 on: August 27, 2020, 01:08:14 AM »
per Keystoner:
Quote
I posit that "ring loading" is exactly as you already *showed* in your tome and what you're now calling "longitudinal cross loading."
...
Bingo.

Quote
per Dan Lehman:
Quote
Only in your mind; others know exactly what is
meant,
Really!
I didn't know that you are in a position to speak for others?
I'll take that on notice.
Not speaking FOR them, but WITH/To them,
and understanding them in return.  We do not
stumble over "ring-loading" in the least; you,
however, are working overtime to try to do so
--take note of that!


Quote
It is possible to place a radial load on a fixed eye.
But the effect upon the knot is to load it
qua end-2-end joint, which IS the point (of the
definition).  We are concerned with the KNOT,
not the eye, per se.

Quote
I think ring loading is ill-defined.
I guess at this juncture, I should challenge you to find exiting engineering literature that defines ring loading? Good luck!
Why would we be looking there?  The term comes not
from the engineering world, but the rockclimbing one;
and we can see there clearly what is meant --meaning
is use.

--dl*
====

agent_smith

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Re: Ring loading is ill-defined (vague)
« Reply #18 on: August 27, 2020, 01:32:59 AM »
per Dan Lehman:

Quote
Bingo
In this case, you missed your call out of 'bingo'!
I will be updating the alleged 'tome' that keystoner referred to.
The term 'ring' loading will take more of an anecdotal role - and be replaced with more specific directions of force.


Quote
We do not
stumble over "ring-loading" in the least; you,
however, are working overtime to try to do so
--take note of that!
I see that you are using "we" again.
Sorry Dan, I'll simply ignore your retort of 'take note of that' (there is nothing to take note of).

Quote
Not speaking FOR them, but WITH/To them,
and understanding them in return.
You are indeed a spokesperson. Very impressive...
While you are speaking WITH "them" - inform 'them' that agent_smith is simply looking at ways to define the direction of loading on a fixed eye.

Quote
We are concerned with the KNOT,
not the eye,
?
Although 'you' may be referring to 'we' and, you now appear to deflect the discussion to a knot...
I on the other hand am referring to direction of loading on a fixed eye.
It seems that 'we' are discussing two different topics.
[ ] I made it clear that I am discussing the direction of loading on the fixed eye of an eye knot
[ ] You (or the 'we') now appear to morph that discussion to a 'knot'?

Quote
Why would we be looking there?  The term comes not
from the engineering world, but the rockclimbing one;
?
Ring loading (of a fixed eye) does not come from any physics or engineering book because it doesn't exist.
And it doesn't (or rather didn't) come from the rock climbing world either... it came from this forum.
The only reason why a select few rock climbers might use that term (ie ring loading) is because it has filtered down via this forum.

Dan,
Not sure what your ultimate purpose is?
Maybe its as simple as defending your current understanding of ring loading and resisting any notional change of redefining it?
In my mind, ring loading a fixed eye of a knot is not well defined and could be arbitrary.
Assigning a direction to the force makes sense to me...


Keystoner

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Re: Ring loading is ill-defined (vague)
« Reply #19 on: August 27, 2020, 12:10:13 PM »
** Warning:  Thread drift ahead. **

Sorry Dan, I'll simply ignore your retort of 'take note of that' (there is nothing to take note of).

Since you're so concerned about clearly defining terms, let me suggest you study the definition of 'ignore,' since from my perspective, instead of ignoring Dan's retort, you did the exact opposite.  You felt the need to respond and let the entire forum know.  From my perspective you have an insecurity that causes an incessant need to get the last word.  See, you're the common denominator.  Every time there is anything contentious in this forum, you're involved.  It's getting old and boring and makes it no-fun to read threads you participate in.

SS369

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Re: Ring loading is ill-defined (vague)
« Reply #20 on: August 27, 2020, 01:16:50 PM »
Ok, we are definitely veering off course now and if anyone wants to continue diverging, I will lock the thread.

This will be unfortunate because the topic is supposed to lead to a discussion about increasing clarity on knotting terminology concerning the phrase ?ring loading?.

In my own opinion, this term has been a bit muddy and and possibly only recognized by more familiar knot tying enthusiasts. I personally don?t see any reason not to discuss potentially better descriptors or nomenclature for this eye loading profile.

Please, get back on topic and perhaps offer some possibilities.

Thank you, the Management.

SS
« Last Edit: August 27, 2020, 02:21:23 PM by SS369 »

agent_smith

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Re: Ring loading is ill-defined (vague)
« Reply #21 on: August 27, 2020, 11:20:08 PM »
Thanks to the moderator for calling out inappropriate behavior, and I doubt whether any apologies will be forthcoming.

To reinforce; this thread is about attempting to more accurately define the directions of loading on the fixed eye of a knot.
I realized that the term 'ring loading' is actually ill-defined - that is, it does not actually define the direction of loading with a degree of precision - while in the process of drafting a paper about #1053 Butterfly.
I felt that 'ring loading' (as a concept) left too many gaps in the way in which a fixed eye could be loaded.

The 'Mobius' Butterfly is an interesting example - and I have attached an image which attempts to draw out the limitations of the default term ring loading.

I accept and understand that some resist any notion of change - and to challenge long-held beliefs or notions of understanding is to invite ridicule.
Nevertheless, the attached image speaks for itself - and it ought to be reasonably obvious that a fixed eye can be loaded in a variety of different directions.

I have already conducted some field evaluation of the Mobius Butterfly as an improvised floating rigging plate.
Due to the unique geometry of this particular corresponding eye knot (from its parent #1053 Butterfly), it remains stable and secure in circumferential loading, longitudinal cross-loading and also radial cross-loading. Interestingly, it is rock solid in a radial cross-loading because the eye legs now mimic through-loading of the parent #1053 Butterfly.

I have to thank Xarax for drawing my attention to the Mobius Butterfly - and the fact that it is TIB and EEL.

Dan_Lehman

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Re: Ring loading is ill-defined (vague)
« Reply #22 on: September 05, 2020, 12:28:52 AM »
Quote
Why would we be looking there?  The term comes not
from the engineering world, but the rockclimbing one;
?
Ring loading (of a fixed eye) does not come from any physics or engineering book because it doesn't exist.
And it doesn't (or rather didn't) come from the rock climbing world either... it came from this forum.
The only reason why a select few rock climbers might use that term (ie ring loading) is because it has filtered down via this forum.

Dan,
Not sure what your ultimate purpose is?
Maybe its as simple as defending your current understanding of ring loading and resisting any notional change of redefining it?
In my mind, ring loading a fixed eye of a knot is not well defined and could be arbitrary.
Assigning a direction to the force makes sense to me...

This is laughable --THIS forum originating the
term "ring loading".  It is a German term (i.e.,
a German equivalent to it), translated into the
lingua franca of our world, and used among
rockclimbers and then from them outwards
as folks become aware (and in need).

And the point of it all is regarding the stability
of an eye knot to endure such loading qua e2e
knot (which is what obtains in your needless
variety of so applying force to the ring).


--dl*
====

SS369

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Re: Ring loading is ill-defined (vague)
« Reply #23 on: September 05, 2020, 02:25:56 PM »
I, for one, do not think that bettering an understanding of a term is unwanted.
Just because some fairly experienced knot tyers grasp its meaning, it is still vague. IMO

As an experiment, one that I have done since the introduction of this thread, I asked a number of people to give a go to defining the term ?ring loading?.

The subject group included age groups, young, middle and advanced, professors, students, some family members (even some Very closely related to a knot tying enthusiast), an engineer, doctor, construction worker, etc., etc.  About 30 people, some of them almost weirded out strangers.
Not once did any of them mention a loaded rope profile and when I followed this with asking about a ring loaded rope, the answer was ?many rings on a rope?.
Most just said, ?Rings loaded onto something.? Or gave the multi-yard stare. 😳

So, if no one wants to participate, please, lets not laugh at another?s desire for clarity.
Positive input is helpful.
SS

Dan_Lehman

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Re: Ring loading is ill-defined (vague)
« Reply #24 on: September 08, 2020, 01:10:26 AM »

As an experiment, one that I have done since the introduction of this thread, I asked a number of people to give a go to defining the term "ring loading".

The subject group included age groups, young, middle and advanced, professors, students, some family members (even some Very closely related to a knot tying enthusiast), an engineer, doctor, construction worker, etc., etc.  About 30 people, some of them almost weirded out strangers.
Not once did any of them mention a loaded rope profile and when I followed this with asking about a ring loaded rope, the answer was "many rings on a rope".
Most just said, "Rings loaded onto something." Or gave the multi-yard stare. 😳

The term is rockclimbing jargon, for Pete's sake.
Shall we ask your sample group about "flash, redpoint ...,
whipper, bombproof, belay, free-solo, dyno, layback, pitch"
and the rest of the array of climbing-specific terms?!

 ???

SS369

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Re: Ring loading is ill-defined (vague)
« Reply #25 on: September 08, 2020, 03:35:35 AM »
Perhaps Pete had too much Sake.  ;)

The idea was to see if the term had any meaning to Anybody.
And, when mentioned >>  "'I followed this with asking about a ring loaded rope, the answer was "many rings on a rope".
So, I'll conduct another pop quiz when I meet up with some friends who climb and get their input.
You do know that some, maybe most rock climbers don't even know or care about those super cool terms. They just climb and enjoy.
Or they use rope for other purposes, such as rescue, construction, etc.

I personally don't see any reason not to further the knowledge base with term clarifying. I am not saying to get rid of the term.
 :)

Dan_Lehman

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Re: Ring loading is ill-defined (vague)
« Reply #26 on: September 08, 2020, 10:08:55 PM »
> I personally don't see any reason not to further the knowledge base
> with term clarifying.

But that is not what is threatened to happen.
Rather, the term is amply well perspicuous
--it is the loading of the eye knot qua end-2-end
joint--, yet A_S wants to split this case into some
myriad things irrelevant to the use and all still
of same knot loading.

--dl*
====

agent_smith

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Re: Ring loading is ill-defined (vague)
« Reply #27 on: September 08, 2020, 10:46:08 PM »
Quote
yet A_S wants to split this case into some
myriad things irrelevant to the use and all still
of same knot loading.
?
I didn't know that 'agent_smith' wants to do this?
Rather, it appears that Dan Lehman wants to assert his notional understanding of the definition of ring loading?

In the first instance, what is a 'ring'?
Most people would define a 'ring' as being circular.

In other posts about the historical source of ring loading...
I have been professionally involved with climbing, vertical rescue and rope access for all of my adult life.
I have never come across the term ring loading until visiting this forum.

Dan, your posts have a tendency to contain language that is belligerent where you encounter a viewpoint that does not align with your notional understanding or personal paradigms.

The simple truth is that a fixed eye of a knot can be loaded in a number of directions.
Why don't you post an image or drawing explaining how you would prefer to define each of the possible loading profiles?
I have already done this - refer to my Butterfly knot images.

Stagehand

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Ring Loading is a clear expression
« Reply #28 on: October 17, 2020, 04:00:01 AM »
Ring Loading is a clear expression. Thank you, Agent Smith, for providing this topic. Thank you for sharing your difficulty finding definition of this important concept. It is understandable that you would have no good experience with this term as it seems to be an idiom only common in American English.   I have been familiar with this term for decades, as it has been used in the entertainment industry. Others in the forum have caught on to the meaning and you should as well, once you have been shown correct usage.
The paradigm case for this term is that of a fixed loop that is trusted for a load all in line with the standing line, but  then this same fixed loop is seen as capable of slipping or breaking with the addition of a significant transverse load.   
In the event production industry, the use of knots is widespread.  For the most part, there are expectations that commonly shared knots will be used. For example, all sandbags hoisted overhead on hand lines shall be tied with the bowline knot.   If an object taken out overhead cannot use the bowline, such as when taking out a service cable, then the clove hitch is likely used. When neither a fixed loop or a hitch is suitable, such as with a box shape, this is when one might see someone attempt something nonstandard like wrapping the loop of a bowline knot around such an object.  The cordage will ?ring? around the box, perhaps even crossing itself to make a ?box wrap.?  This is a real time problem that invites the succinct warning, ?You are going to ring load that knot.?   The warning is that the knot may slip or break because of the added transverse tension and that there is a risk of a catastrophic failure.  The expression is a fair warning and serves the purpose exactly.
The usage then extends away from cordage ringing an object to other cases, never leaving the primary condition of a fixed loop that can fail with transverse tension.  Consider a heavy object to be hauled out, a breasting line to be attached which will be used to pull the object out of the plumb line. If the heavy object is hauled out on a bowline knot and the breast line is attached through the fixed loop, then there is the possibility of a transverse tension on the loop.   Again, the warning is that the knot may be ring loaded and catastrophic failure could be the consequence.
Agent Smith, your attempts to understand this concept by looking for a knot tied around a circular  object are too narrowly focused in asking for some specific shape to provide the important condition and your objections are not well placed for not seeing the central issue, that of a knot that is otherwise trusted but not when a transverse load is added.   
Consider the many knots that may be cinched around circular objects. These knots are called hitches.  If they may fail, they are not said to be ring loaded as you define the term. They are called unsecure hitches. 
Agent Smith, you are critical of our fellow forum members who find the expression ?ring loading? unproblematic.  They share the use of the expression with purpose but you somehow think they don?t or shouldn?t Perhaps this common use of language that is accepted by an entire industry and several forum members is unacceptable to you because you have a more exacting analysis.   
To this exacting purpose, Agent Smith, you bring vocabulary from hydraulics into the discussion. The terms that you list, longitudinal load, radial load, circumferential load, these are  the mutually orthogonal vectors of cylindrical coordinates. Since each of the three illustrations from you, for the three vector directions, point in just one direction, outward, I am not sure you have the concept. You say that these are further considerations that need to be included to understand ?ring loading? or similar phenomena.   It could be asked, why bring in hydraulics?  Why not analyze knots and rigging for the tensile structures that they are?
It is surprising, as you present yourself as a professional in the use of rigging, that from your opening statement of your thread, you show an inexplicable view of how forces work in knots.  You open this topic by saying that ring loading should not be understood on the model of a bend which is pulled apart by a load because in the model of ring loading, as you say, the load is diminished to one half for each leg of the fixed loop. But your assumption is only suitable for the simple case where the load on the fixed loop is hanging down, in one direction, where there is no deflection, where there is no ring loading!  If there is any deflection, such as in any bridle, then the load in each leg is more than half the load.  Indeed, if the bridle is shallow or if the fixed loop is ring loaded, then the tension in each leg can greatly exceed the weight of the object to be hoisted.  This phenomenon situates both the relevance and the significance of the term, ?ring loading,? in the avoidance of catastrophic failure. This is so fundamental to industrial rigging that it calls into question your experience.  Have you never installed a rigging point across a span?  If you had, you should have felt the transverse component of the load.  You would have known how dramatically this force increases with the shallowness of the bridle.  This would have figured into your calculations of a safe working load. It is the same phenomenon within a ring loaded knot. 
Agent Smith, thank you again for this important topic and thank you for all of your work in and out of this forum.  I am glad to be able to contrast my views on knots with your views.  I welcome a reply to this or any of my remarks.
« Last Edit: October 17, 2020, 04:04:34 AM by Stagehand »

agent_smith

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Re: Ring loading is ill-defined (vague)
« Reply #29 on: October 19, 2020, 10:12:02 AM »
In reply to Stagehand:

I have read your post and some of the language is taking on the character of a personal nature.
I cannot understand why comments of a personal nature are warranted.

All I am doing is presenting information in an attempt to draw well considered discussion without resorting to personal attacks.
A forum moderator has already issued some warnings to keep the discussion polite and non belligerent.

I have extracted passages from your narrative that I believe are unnecessary and might attract the attention of a forum moderator.

I have formed a view that the following comments are of a personal nature and/or taking on a character that is borderline offensive:

Quote
Thank you for sharing your difficulty finding definition of this important concept. It is understandable that you would have no good experience with this term as it seems to be an idiom only common in American English.
I have no such 'difficulty'.
I am simply interested in discussing various loading profiles on the eye of a fixed eye knot.
Anything beyond that basic framework is extrapolation.

Quote
Others in the forum have caught on to the meaning and you should as well, once you have been shown correct usage.
Have they? Okay - this suggests I am deficient, or not grasping commonly understood concepts? This is borderline offensive.

Quote
It is surprising, as you present yourself as a professional in the use of rigging, that from your opening statement of your thread, you show an inexplicable view of how forces work in knots.
This comment is completely unnecessary and borderline offensive.

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Agent Smith, you are critical of our fellow forum members who find the expression ?ring loading? unproblematic.
No - I'm not.
I am simply discussing loading profiles on the eye of a fixed eye knot.
If you re-read all of the previous posts, you will see that I am not the protagonist - you have misunderstood my intent.

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This is so fundamental to industrial rigging that it calls into question your experience.
This comment is unnecessary and borderline offensive.

Quote
Have you never installed a rigging point across a span?  If you had, you should have felt the transverse component of the load.  You would have known how dramatically this force increases with the shallowness of the bridle.  This would have figured into your calculations of a safe working load.
This comment is unnecessary and borderline offensive.
It suggests that I am lacking or deficient in some way - and/or don't measure up to industry standards.

...

Where do we go from here?
Is it possible to enter into a discussion in a way that avoids comments of a personal nature?
Why engage in such behavior?
What motivates you to engage in such behavior?

EDIT NOTE:

On a positive note, I had been in various discussions about terminology to describe the possible directions of loading on the eye of a fixed eye knot:
For example:
[ ] Axial loading (the eye is loaded along the direction of the SPart)
[ ] Transverse loading (the eye is loaded perpendicular to the SPart)
[ ] Circumferential loading (hoop stress - the eye is expanded in multiple outward directions
« Last Edit: October 19, 2020, 10:23:48 AM by agent_smith »