Author Topic: History of knots (discoverers)  (Read 15325 times)

agent_smith

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History of knots (discoverers)
« on: January 27, 2007, 02:46:12 AM »
I am conducting research into who 'discovered' certain climbing/mountaineering knots.

Thus far, i have only confirmed 1 'discoverer':
[ ] Dr Kark Prusik - discoverer of the 'Prusik hitch' in 1931.

EDIT: Werner Munter is NOT the inventor of the Munter hitch! He is merely one of the first people to introduce it to the USA (google searches). The Munter is listed in Ashleys as ABOK #1818 and a variant at ABOK #1195. ABOK was first published in 1944.

I am thinking that the term "discoverer" may be more accurate because certain knots/hitches may have been used in ancient times but then forgotten... Also, a discovery may have been made by a group rather than an individual (or perhaps a society or community).

I realise that there are conflicting names for knots in the world - i am using the conventional names as widely recognised by Australian climbers (I live in Australia).

These knots are:
1. Figure 8 on the bight - discoverer unknown
2. Re-threaded figure 8 (also known as a rewoven figure 8 or figure 8 follow-through) - discoverer unknown
3. Adjustable double figure 8 on the bight (also known as ‘bunny ears’) - discoverer unknown
4. Clove hitch - discoverer unknown
5. Double fishermans knot (sometimes known as a grapevine knot) - discoverer unknown
6. Prusik knot - invented by Dr Karl Prusik in 1931
7. French prusik (a variant on the traditional prusik - also known as an autoblock) - discoverer unknown
8. Tape knot (known in the USA as a ring bend or water knot) - discoverer unknown
9. Alpine butterfly knot - discoverer unknown
10. Munter hitch (also known as an Italian hitch or HMS) - discoverer unkown (Werner Munter is credited with introducing it to the USA)

I dont have the Ashley book of knots at this time - but I am not sure if the history of each knot was indicated.

I have searched high and wide on the net (google) but again no luck - other than for the Prusik hitch.

I would appreciate if someone could help me


Thanks,

agent smith
« Last Edit: February 05, 2007, 12:41:51 PM by agent_smith »

sankwe

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Re: History of knots (inventors)
« Reply #1 on: February 02, 2007, 01:26:52 AM »
Try the book "The history and Sciencs of knots" by Turner and van de Griend. It has a lot useful information and a good list of sources.

But....you may find that some of these knots date to antiquity. The clove hitch, Double fishermans knot and figure eight knot and it's variations most assuredly do.

Bill Molenda
Never be afraid to try something new
The Ark was built buy a single amateur, the Titanic was built by teams of experts

Dan_Lehman

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Re: History of knots (inventors)
« Reply #2 on: February 02, 2007, 05:21:56 AM »
I am conducting research into who invented certain climbing/moutaineering knots.

Thus far, i have only confirmed 2 inventors:
Werner Munter (the inventor of the Munter hitch - also known as the HMS) and Dr Kark Prusik - inventor of the prusik in 1931.
I must question your research:  from where did you conclude that Munter should
be credited with the hitch?  --Frank Ruzo, of Germany, might want a claim in that;
and elsewhere one can read of Italian belay pioneers who developed its use.
Knots have a way of popping up in different places at odd times, without
interconnections between each occurrence.

Quote
1. Figure 8 on the bight - inventor unknown
2. Re-threaded figure 8 (also known as a rewoven figure 8 or figure 8 follow-through) - inventor unknown
Silly names merely denoting different tying methods.  The knot is amply old, and you
are unlikely to find anyone claiming invention of it.

Quote
3. Adjustable double figure 8 on the bight (also known as ‘bunny ears’) - inventor unknown
This is formed by a method that is generally applicable to EVERY loopknot, I'll conjecture
--there, I've invented quite a boatload for you!  (illustration is left as an exercise for the student)
Quote
4. Clove hitch - inventor unknown
--as old as cordage

Quote
9. Alpine butterfly knot - inventor unknown
You can omit the "Alpine" and read about this in Wikipedia's entry, which I think carries
information I added, still.  --at least in 1928, Wright & Magowan's report to the Alpine Club.

Quote
I would appreciate if someone could help me
Again, knots have a way of popping up in different places.  Is the first-known presenter
of a knot deserving of special recognition?  You might reflect on this.
"Blake's Hitch"--a good friction hitch, used by arborists--was popularized (and one may
believe, separately discovered) by him in 1994; but it was also presented some years
earlier by Heinz Prohaska,  in Austria (your area!), and in America in a caving journal.

There is another sort of "invention" to be found (and abolished) in knotting; read about
it in Wikipedia's entry for the "Heaving-line Bend"!

--dl*
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Lasse_C

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Re: History of knots (inventors)
« Reply #3 on: February 02, 2007, 08:08:56 AM »
Most of the more basic knots are, as Dan noted, as old as cordage. In other words they date back thousands of years, long before any written history or record existed. (Actually, in some places of the world, knotted cords were the first "written" records!  ;)) I think you will find it hard to dig out a record of the inventor(s) - or that it even exists! In some cases you might find someone who claims to be first and true inventor (they still pop up from time to time) but how do you know that is true?

I must confess that I am a little curious, though: Why is it so important to find out the inventor?

Lasse C
« Last Edit: February 02, 2007, 08:09:30 AM by Lasse_C »

agent_smith

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Re: History of knots (inventors)
« Reply #4 on: February 04, 2007, 03:45:48 AM »
Thanks Dan_Lehman.

You are correct - I had trouble posting earlier as my first attempt was blocked as spam. I tried again and it too was identified as spam and then I grew frustrated and basically threw the towel in...

On my first post - I was too hasty in posting info on Werner Munter... as he is certainly not the discoverer of the munter hitch (even though it bears his name).

The reality (as far as I can ascertain) is that he was the first person to introduce it to the USA and hence that nation popularised the name of the hitch with Mr Werner Munter.

I acknowledge that this hitch appears in Ashleys book of knots (ABOK) as ABOK #1818 (Crossing hitch) and also a variant is illustrated at ABOK #1195 (The Zig Zag knot). Obviously, ABOK predates Werner Munter!

ABOK doesn't indicate the history of knots #1818 or #1195.

As for the Prusik knot (better term is hitch), it appears that Clifford Ashley also illustrates this at ABOK #1763.

My research pointed me to Dr Karl Prusik is its discoverer in 1931.

The ABOK was first published in 1944.

I am willing to accept the conventional view that Dr Karl Prusik is its 'discoverer'.

In fact, I hold the view that the word "Inventor" should be substituted with "discoverer".

I accept your view Dan_Lehman that in reality, the true discoverer may never be known and that really what is taking place is a re-discovery! Perhaps we will never know who discovered/invented the wheel either...

Be that as it may, this will not stop me from trying to piece together a clearer understanding of mankinds (or politically correct humankind's) history of knots.  I like to know that it was Hillary and Tensing who were first to stand on the summit of Everest and that it was a Norwegian Roald Amundsen who first stood at the South pole or the real discoverer of penicillin - I am somewhat driven to uncover facts - and believe in giving credit where credit is due. I guess I am damned for doing so.

In terms of climbing knots, as a passionate climber myself - and a developer of new training technologies for the industry of climbing - I want to keep alive our historical roots.

My specific interest is to try to find the point in Earths history when a particular knot became accepted for climbing applications and who was responsible for advocating its use. There are also some legal and science issues that I trying to address here in Australia (the great land downunder!) - I am called upon to give instructional advice to large companies and professional rope rescue agencies and of course, there needs to be compelling and science based reasoning for each knot that is included on the curriculum (ie why teach knot A to rescuers instead of Knot B etc)...

An example is the linemans loop ABOK #1053 is linked to a fellow named J.M. Drew in Ashleys text - but no other history is given. What really interests me is when the linemans loop entered into climbing usage and when did the name of the knot change to Alpine butterfly knot? Which men/women were advocates of this knot for climbing? It is the crucial transition of a particular knot into mainstream climbing applications that interests me.

The Alpine butterfly knot (AKA linemans loop) is now widely regarded as an essential knot for climbers and is taught in virtually all instructional circles.

I really appreciate your thought provoking response Dan_Lehman and hope to hear more from you!

I will post again with an example of the work I am doing.

Thanks,

agent smith
« Last Edit: February 04, 2007, 10:50:21 PM by agent_smith »

agent_smith

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Re: History of knots (inventors)
« Reply #5 on: February 04, 2007, 05:07:28 AM »
To Dan_Lehman (or anyone else who has answers!)...

.......................................
>>You can omit the "Alpine" and read about this in Wikipedia's entry, which I think carries
information I added, still.  --at least in 1928, Wright & Magowan's report to the Alpine Club.>>
........................................

Tried Wikipedia search using "Butterfly knot" but no specific info came up... have also googled "Wright & Magowan's 1928 report to the Alpine Club" but no luck. It turns up hits linked to the AAC but then I have no luck drilling down to find specific info...

I presume you meant "Alpine club" to mean American Alpine Club?

Do you have a www address for this information? And what info should I expect to find on the Apline butterly knot or rather - "Butterfly knot?"

If you could help me find more info on the Apline Butterfly knot / Butterfly knot / Linemans loop I would be gratefull.

I am also conducting some research into the Rosendahl bend (also known as the Zeppelin bend). Could not find an ABOK reference. The closest ABOK is the hunters bend at ABOK #1425A.

I am very interested in strong/secure/stable methods of joining two climbing or abseiling rope togther - the Rosendahl appears well suited to such applications, perhaps superior even to the Double fishermans (AKA Grapevine) ABOK #1415.

Specifically, I have experimented with a variant to the Rosendahl bend by adding and extra wrap to both tails.

I cannot find any reference to this variant which I tentatively call the "Double Rosendahl bend" (ie, its a Rosendahl with an extra wrap on both tails).

I am going to commission some load tests with the single and double Rosendahl bends and compare results with a control (same rope but unknotted) and then a round of field testing with a backup belay safety line.

I will also instruct the testing authority to conduct cyclic load testing to collect data on stability/security.

A further round of testing with an ABOK #1415 to compare and contrast against the Double Rosendahl will also be done as a control.

Dan_Lehman, have you any info of any existing data on the "Double Rosendahl bend?"

I am of course hoping to start a quiet little evolution (but not a revolution) in climbing and rescue circles to finally challenge the conventional wisdom that ABOK #1415 is the emminent joining knot. I am hoping that test data backed up with field testing will demonstrate the "Double Rosendahl bend" to be a superior joining knot.

Why, you may ask? Because ABOK #1415 is difficult to untie after loading. This problem has sparked endless debate and compelled many in rescue and climbing circles to try variations to join 2 ropes. You may have heard of a number of worrying deaths in relation to abseil descents where certain joining knots have mysteriously failed. You may also have heard of the so-called Euro death knot (EDK) or perhaps known as an overhand bend with both tails exiting together on same side. Others have tried to use a figure 8 again with both tails together and exiting on same side (aka abnormal F8, flat F8, etc, ...)...


agent smith

agent smith
« Last Edit: February 04, 2007, 05:15:20 AM by agent_smith »

Dan_Lehman

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Re: History of knots (inventors)
« Reply #6 on: February 04, 2007, 06:09:41 AM »
Firstly, I don't mean to discourage but rather to temper your enthusiasm about learning
of "inventers" of knots:  expect that there might be several, and that sometimes the mere
finding of a knot form doesn't reveal its full use/potential--e.g., the Munter H./MB
is the form of the Crossing knot, but though Ashely presented the latter, he hardly hinted
at the use for belaying a falling rockclimber.

To Dan_Lehman (or anyone else who has answers!)...
.......................................
Quote
You can omit the "Alpine" and read about this in Wikipedia's entry, which I think carries
information I added, still.  --at least in 1928, Wright & Magowan's report to the Alpine Club.
........................................

Tried Wikipedia search using "Butterfly knot" but no specific info came up....

I presume you meant "Alpine club" to mean American Alpine Club?

Do you have a www address for this information?
No, English Alpine Club.
Here is a URLink to printed pages of the full article, which includes these authors'
introduction of the Butterfly (and their stated rationale for choosing that name):
http://tinyurl.com/ybrxop
[2014-04-17 edit to try a working URLink, which offers 2 versions (hi/lower-res):
 http://charles.hamel.free.fr/Alpine_journal/
]
(sorry for the fine print; if need be, I could snailmail a slightly bigger copy)
Now, I'm not sure how far back one can trace lineman use:  IIRC, Charles Warner in his
chapter Life Support Knots in History & Science of Knots concludes that it's unclear
whether there was any actual use of whichever knot--confusion about what was used.

Quote
I am also conducting some research into the Rosendahl bend (also known as the Zeppelin bend).
Could not find an ABOK reference. The closest ABOK is the hunters bend at ABOK #1425A.
--or #1408.  This isn't in ABOK, and if you look on-line I think you can find a (MotherJones?)
reprint of the magazine article that apparently associated "Zeppelin" to this otherwise unnamed knot,
though the quoted advocate there I believe said that users referred to it as "R---'s" knot.
It was later "invented" by Bob Thrun (author, Prusiking[/u]), and piqued his interest in learning
of its history--and this is the first publication of it that he has found.
(As I invented ('73) SmitHunter's bend, and seeing it on the cover of the Morrow Guid to Knots piqued
my interest such that I wrote to this policeman Budworth in England and ... --the rest is history, or currency! :o)

Quote
I am very interested in strong/secure/stable methods of joining two climbing or abseiling rope togther
 - the Rosendahl appears well suited to such applications, perhaps superior even to the Double fishermans
 (AKA Grapevine) ABOK #1415.
And the astute knots person should here quickly ask Why?, meaning that folks have been abseiling
for decades, and it is pretty easy to find debates about the ARJ (Abseil-Ropes Joiner) knots in contention:
the Offset Overhand Bend (OOB, aka "EDK" = "European Death Knot", "Double Overhand", "Thumb Bend")
is recommended by some rope makers and the UIAA.  Back it up with an Overhand in the thinner line around
the end of the thicker, and it's even dandier.  Make a full round turn of the binding rope (one first holding the
opposed lines together where they enter from opposite directions)--which makes a Figure 9 in that rope--
and you have ample security against "rolling"/flyping.  Strength is simply NOT an issue--full stop/PERIOD!

Quote
Specifically, I have experimented with a variant to the Rosendahl bend by adding and extra wrap to both tails.
Which will increase bulk with the only measurable effect IN USE of being more difficult to haul down over rock.
(For another fun time, try making the each tail wrap around the opposite standing part before being tucked out
--giving the SParts a loop forwards vice their u-turn backwards.)  Ashley's #1452 should do whatever you seek
with Rosendahl's, and #1425 will be much more secure when slack, yet still easily untied (takes more work,
but it comes).

Quote
I am going to commission some load tests with the single and double Rosendahl bends
and compare results with a control (same rope but unknotted) and then a round of field testing
with a backup belay safety line.
We'll await your report of results.  It will be good to (1) take photos of the knots as tied, and as
tension on them reaches, say, 40% of the rope's strength.  If you have to make a loop in order
to peform the testing, MAKE A KNOT IN EACH SIDE OF THE LOOP, so to remove the issue
of rope-lengthening from knot compression on one side only!!  (and to have one
unbroken yet heavily loaded specimen surviving the test, and knowledg that TWO knots got
to XXX pounds load okay!).!!!  (I.e., in some testing of the Grapevine the rope breaks AT THE
PIN, and it's speculated that this results from the material feed from a compressing knot
making the rope lengthen on that side and so move around the pin at high load.)

Quote
A further round of testing with an ABOK #1415 to compare and contrast against
the Double Rosendahl will also be done as a control.
Or, you might regard extant data on this knot sufficient to make conclusions, and instead
spend you precious resources on testing something not otherwise tested much, such
as #1425!  (One fellow has done Knot-A vs. Knot-B testing of many knots, and 1425
(NOT "1425a", NOT SmitHunter's bend--the REAL/original "1425", by Ashley) fared well!

Quote
Dan_Lehman, have you any info of any existing data on the "Double Rosendahl bend?"
In the above testing this knot was entered and had mixed results vs. 1425a, 1452, & less well vs. 1425,
though IIRC there was the odd situation of A beating B 3-0, B beating C 3-0, and then A beating C only
3-1 or even 3-2 !?  (I've seen volleyball matches like that.)

Quote
I am of course hoping to start a quiet little evolution (but not a revolution) in climbing
 and rescue circles to finally challenge the conventional wisdom that ABOK #1415 is the
emminent joining knot. I am hoping that test data backed up with field testing will demonstrate
the "Double Rosendahl bend" to be a superior joining knot.
Then you are in for a rude awakening that test results have been in some sense obtained
through decades of usage, and NO KNOTS FAIL IN PRACTICE from weakness, in these
kernmantle user communities--safety factors better ensure this, for one thing!
More important considerations are:  familiarity (the new always loses to the established, here),
ease of tying (sadly, familiarity biases this), interchangeability with users (do things like everyone
else and it's easy; go pioneering and it's a continual battle).  And so on.
Not that some better thinking isn't needed (you will be surprised to read Wright & Magowan's
words--this is what THEY tried, in 1928:  you can assess their success by considering how
well you know the Sennit & Reever bends, e.g.!).

Quote
You may have heard of a number of worrying deaths in relation to abseil descents where certain joining
knots have mysteriously failed. You may also have heard of the so-called Euro death knot (EDK) or perhaps known
as an overhand bend with both tails exiting together on same side. Others have tried to use a figure 8 again with
both tails together and exiting on same side (aka abnormal F8, flat F8, etc, ...)...
This I know well:  there are more rumors per rare actual incident than press reporters on a sex
scandal--all throwing wild assertions devoid of thought & research.  I know of ONE mystery with the OOB,
and one death alleged for the Offset Fig.8 (and I disdain the names "flat" & "abnormal"--they are neither).
I've indicated above how to redress concerns for the OOB, and the 2nd works as well for the Fig.8.
FYI, one of the folks who examined the ropes of the British climber's death from the presumed capsizing
of the Offest Fig.8 continued to recommend this knot for canyoneering ropes--he called the climbing
ones of the failure "cables" (stiff).  The OOB is simplest, most compact, and well known (even if misunderstood
by many); getting either the back-up stopper or the full turn prelude seals this knot's fit for the purpose.
--though it hasn't stopped me from fiddling numerous competitors, still !!

motto:  have rope, will fiddle

--dl*
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« Last Edit: April 18, 2014, 08:40:35 PM by Dan_Lehman »

agent_smith

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Re: History of knots (inventors)
« Reply #7 on: February 04, 2007, 12:40:58 PM »
For some reason, Dan_Lehmans most recent post does not appear in this thread - and yet, I could see it through another search in google! Dont understand why...

Anyhow, Dan_Lehman, I want to extend my gratitude to you for your thoughtful and well informed posts...

In relation to the ABOK #1415, it will be necessary to conduct testing on this knot as a control.

I realise that others have already tested this and many other knots but the problem is that most of these tests were not conducted by a ISO 9001 or NATA certified testing facility - they were usually done informally.

I need data that is 3rd party certified - in Australia, NATA is the highest quality assurance you can get and it is recognised in courts of law. I am not going to simply use my own 5 ton load cell (a dynafor model) in my backyard.

I realise that slippage and/or stretching around the pins on the ram may have distorted some test results in the past. Dan_Lehman, your suggestion to form a loop (or an endless sling) is something I had planned to do - with two identical knots as you indicated. This means that two (2) identical lengths of rope will be formed into a sling - there will therefore be two identically tied knots. When the rope sling is placed around the pins on the ram, great care will be taken to ensure symmetry/balance - meaning there will be one knot on each leg of sling (as a mirror image on both sides).

Of course, first we will need to establish the MBL of an unknotted length of rope of the exact same type/model/brand/diameter. The formation of a rope sling will effectively double the MBL of the rope. With the baseline MBL of the unkotted rope, we can then determine a % strength loss attributable to the knot (and the eventual failure load).

As far as I can determine, no body has conducted 3rd party NATA/ISO 9001 certified load testing of the Rosendahl and double Rosendahl bends.

The test data of the Rosendahl bends will be compared to the test data of the ABOK #1415.

Even though others around the world may have conducted testing of the ABOK #1415, it will be essential to use the exact same type/brand/model/diameter/age ropes throughout all the tests.

Agent smith obviously has no way of knowing precisely what type/brand/model/age of rope that were previously used. I have noted some US and Australian tests which have been posted on the net but unfortunately, neither test was 3rd party certified.

As I previously indicated, the principle problems with the ABOK #1415 are:
1. It is very difficult to untie after loading; and
2. It can get stuck at the edge of the cliff during rope retrieval attempts (etc where ABOK #1415 was used as a joining bend to unite 2 climbing ropes).

I hold the view that the primary risk of a stuck rope is at the edge as the knot tries to translate through 90 degrees. Once the joining knot has cleared the edge, the risk of subsequent entrapment (or just getting stuck again) is low. Momentum is the key - that is, you apply a constant pulling force to maintain the momentum and gravity does the rest. I have significant experience with rope retrieval and although the risk of a joining knot becoming stuck after it has cleared the edge is possible, it is a very low risk (provided the climbing party have selected a suitable descent point and 1st person down has confirmed with a test pull)...

I have compared the profile of a double Rosendahl against an ABOK #1415 and I can confirm that the double Rosendahl has less width (ie smaller circumference) but greater length. However, the shape of the double Rosendahl is interesting in that it is angular. In my opinion, the shape of the double Rosendahl suggests that it is less likely to snag at the edge of the cliff than an ABOK #1415. Field testing will verify this (I hope).

I am not an advocate of the offset overhand bend (OOB) or the offset figure 8 (OF8). These knots/bends tend to shear the rope apart in 180 opposition and can cause the rope to roll/capsize. I have no data for wet ropes or for ropes tied together of different diameters.

...

I withdrew my earlier (and hasty) indication that I was searching for inventors of knots - I realise that I should have used the word "discoverer" instead.

I also withdrew my incorrect statement that Werner Munter was the inventor of the munter hitch - he was not.

...

Thank you for the info on Wright & Magowan. Have downloaded and am studying the 'fine' print! I love this kind of literature - it is a piece of our world history and its an important document...

I will inform you when I am able to get rolling on the load testing and report back in this forum. I will also report on field testing of rope retrievals using the double Rosendahl bend. Dont worry, I'll take plenty of photos!

Agent smith
« Last Edit: February 05, 2007, 01:46:38 AM by agent_smith »

Dan_Lehman

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Re: History of knots (inventors)
« Reply #8 on: February 05, 2007, 03:12:05 AM »
I am not an advocate of the offset overhand bend (OOB) or the offset figure 8 (OF8). These knots/bends tend to shear the rope apart in 180 opposition and can cause the rope to roll/capsize. I have no data for wet ropes or for ropes tied together of different diameters.
But you should realize that neither the ultimate weakness (relative to the potential of other knots,
NOT to the task for which it's employed--holding approximately one HALF of a climber's weight!)
nor the vulnerability to capsizing at higher loads should be a concern for use as an ARJ knot.
And, since you are interested in putting test results to some of your conjectures, you should do
the better-suited (i.e., offset) bends the fairness of testing them.  There is one Australian (sorry,
I had you in cooler & European climes above) report on the more important characteristic of
ARJ knots:  Bushwalker Rescue ..., by David Drohan; he tested the knots' resistance to being
pulled over an edge.  (Your question of strength is, again, entirely irrelevant to ARJ use.)

Please see how the simple variations to the OOB behave--i.p., at what load, if any, will they capsize?
Quote
Back it up with an Overhand in the thinner line around the end of the thicker, and it's even dandier.
Make a full round turn of the binding rope (one first holding the opposed lines together where they enter
from opposite directions)--which makes a Figure 9 in that rope--and you have ample security against "rolling"/flyping.
Maybe you should put your faith in testing and come to see a way to remove your fears of the OOB
--even if only by these minor amendments.  (As I said, I've oodles of candidates for this, but the OOB is going
to win hands-down on simplicity, ease-of-learning/-tying (for tired, hurried, in-fading-light climbers late to
bail out of a climb).  And, being asymmetric, it can actually perform better (my conjecture, so far)
with typical imbalanced rope types (7mm low-elongation haul rope, 10.x mm main climbing rope
--orient it such that is the thinner rope that would have to be forced around the thicker in capsizing)!
(I'll point out that the OOB can be sort of dialed in exact orientation once tied--so that either of
the ropes might make a backwards loop to the others forward arc, or both equally arc to the side;
try this and see--it's another aspect not well tested, except insofar as one might suppose the years
of usage have given each orientation a fair shake or few.)

To put this in other terms, re your testing:  as the Grapevine has been tested to be from 55% (just saw
this for nylon & polyester double-braids, in SAIL mag., Feb-07 pp.82-4-6 (and seems too LOW)) to 80%
or so, I don't see ANY result you might get from a break test that will matter to anyone much.  (And I'd
be skeptical of a strength as great as for the G., also--and it remains an issue as to how to dress & set it.)
So what do you gain?
If you test the OOB variations above, you might be able to show improved stability, which then can
easily be seen to attach to a knot already renown for ease of movement over rough surfaces.

--dl*
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agent_smith

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Re: History of knots (discoverers)
« Reply #9 on: February 05, 2007, 01:15:14 PM »
Once again, thanks for your considered posts in this forum Dan_Lehman.

In a nutshell, I have been unable to source 3rd party certified test data on any knots/bends/hitches. I develop various learning resources for climbing groups and other professional rope rescue teams. The rope rescue teams are professional people who are at times under resourced in terms of tracking down & implementing scientifically reproducible test data on ropes, knots and equipment.

In all the research I have done, I must confess that there is very little NATA/ISO certified test data out there in the public domain.

There is an over-supply of non-certified data and in particular data from well meaning people who might do a pull test with their vehicle and a tree anchor etc.. and then post their results on the net.

Even for those people that have access to a load cell (like I do), it still isn't enough to do simply carry out your own backyard tests and then publish data. The community I live, play and work in is growing smarter and demanding more reliable 3rd party backed data. If it isn't 3rd party certified by an external test laboratory with NATA or ISO 9001 credentials then it isn't taken seriously by professional people - its simply regarded as 'anecdotal evidence'.

Dan_Lehman, do you have any NATA, ISO or other quality certified test information on knots/bends that is recent? If so, would you be willing to share it with me?

If not, would you be willing to contribute to drafting up a set of test guidelines/parameters that I can supply to the testing authority. Keep in mind that the majority of the lab rats that run these NATA/ISO facilities are not climbers/abseilers and therefore dont have our depth and breadth of knowledge. They need to be led by the hand.

I will need to use controls in the tests to compare the results against. I am willing to spend a bit extra and include the OOB and OF8.

But, I will also need to include the ABOK #1415 to compare data against.

I also have more than a passing interest in the Rosendahl bend and more specifically, the double Rosendahl bend. In Australia, the jury is out on the OOB and OF8 as rope joining bends for abseil descents - regardless of ultimate strengths and % strength loss in the rope. As I have stated before, with regard to the ABOK #1415, it really comes down to 2 key criticisms:
1. It is very difficult to untie after loading; and
2. It can get stuck at the edge of the cliff during rope retrieval attempts (etc where ABOK #1415 was used as a joining bend to unite 2 climbing ropes).

It is these two criticisms that have compelled climbers to seek other alternatives to overcome the above limitations.

In some rescue groups, the OOB and OF8 will never be accepted (in my lifetime).

I think the double Rosendahl bend could be a contender to once and for all, offer a compelling reason to make a switch. We'll have to wait for the lab test results and then the field test results.

I realise that nylon ropes become 'plasticized' when wet and this has a similar effect to heating the rope to 80 degrees C. Iced ropes are even worse. My budget wont stretch far enough to include wet and icy rope tests on the OOB and OF8 + the Rosendahls.

Have you noticed the angular shape of the Rosendahl in comparison to the ABOK #1415? (I'm sure you have...). It will be interesting to do field testing of rope retrievals over a 90 degree edge.

Another issue is that i want to limit the total number of 'need to know' knots to 10 or 11 at most. Every conceivable climbing and rope rescue scenario must be covered by the 10/11 knots. Obviously, a head full of too many knots can be confusing and  might hinder rather than aid in a real rescue situation.

So Dan_Lehman, would you be willing to assist with writing a test procedures for some knots that even a non-climbing lab technician could understand? - (the instructions must allow for reproducibility). I would of course be willing to post the data in this forum and even in a private email to you.

agent smith
« Last Edit: February 06, 2007, 12:47:56 AM by agent_smith »

Fairlead

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Re: History of knots (discoverers)
« Reply #10 on: February 05, 2007, 11:03:35 PM »
I am surprised not to see the name Robert Chisnall mentioned in this thread yet - have you read any of his work or contacted him to see what data he has?
His solution to your problem with the Fisherman's Knot (or whatever name you know it by) is the 'Adjustable Bend' which he is said to have devised sometime before 1982.  Added to that he almost certainly should be on your List of possible Knot "Inventors".


Gordon

agent_smith

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Re: History of knots (discoverers)
« Reply #11 on: February 07, 2007, 12:25:20 PM »
Fairlead, I have heard about Robert Chisnall but I do not have any of his books/work.

I have searched via google but there is no contact info that I can find... can you assist? My interest is chiefly in relation to knots used in climbing & rope rescue applications.

Dan_Lehman, do you have any leads regarding access to 3rd party certified test data on knots? If not, would you be interested to assist in drafting robust test instructions for climbing illiterate lab technicians?

I am certainly willing to share the test data with members of this forum...

agent smith

Dan_Lehman

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Re: History of knots (discoverers)
« Reply #12 on: February 10, 2007, 05:26:36 AM »
delayed response, but I've been a bit under the weather, alas (cough-cough, sniffle)

re writing rules for testing:

Hmmm, ISO I believe has a Technical Committee / SubCommittee / Working Group
related to this; cf:  www.uni-tex.it/commissioni-gruppi.html .
For general information about ISO (I like the way the name was chosen:  to be as
close to the Greek isos (meaning "equal") possible--sounds like an English-speaker's
recommendation), cf www.iso.org/iso/en/stdsdevelopment/whowhenhow/how.html
and around.

As for knowing of any 3rd-party testing, hmmm:  the UK's HSE (Health & Safety Executive)
has commissioned a couple of studiies for industrial rope access, but I'm not sure if they
qualify as "3rd party" testing (of which I see they apparently have chapter 9 of one also
available separately (Prusik knots).  Cf
209.85.165.104/search?q=cache:WeXzPTw49NcJ:www.hse.gov.uk/RESEARCH/crr_pdf/2001/crr01364.pdf+HSE+knots+figure+of+ten&hl=en&ct=clnk&cd=3&gl=us
(html of a pdf file).  I can't say that I'm so favorably impressed with Lyon's testing over
what I've seen elsewhere (i.p., few samples and some odd test cases:  1@ of knot-A vs. knot-A,
knot-B vs. knot-B, & knot-A vs. knot-B for loopknots, e.g.!?)

Quote
Another issue is that i want to limit the total number of 'need to know' knots to 10 or 11 at most.
One might take a diffferent perspective here, as way to get more variety/flexibility:
teach people knotting, not knots per se, so that on encountering various rope problems,
it's not purely a look-up-the-index function.  But there are slippery slope aspects to this.

Quote
I'm willing to spend a bit extra and include the OOB and OF8.
Thanks, but, please, not the OF8 but one of the modifications of the OOB I described
above (I'm partial to the Offset 9-Oh, where the full turn is made at the throat of the knot;
the stoppered variation of course is easier to understand and tie).  There is enough
of a case made against the OF8, and it's a knot with some various orientations to
consider, which only complicates the testing (if done for all) or renders it mute (if it's
silent about them).  For that matter, realize that the dialiing aspect will also likely
have influence, so even for the OOB which has but one obvious dressing,
how the ends are set has 3 rough points, roughly determinable by which way the
ends point.  And, for just-in-case's sake, testing variations with the thinner/thicker
ropes in both throat-choking & twin positions should be done--one would want to
issue cautions about this, if necessary.

--dl*
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