Author Topic: Knot testing - Life support knots - procedures and results  (Read 38494 times)

Dan_Lehman

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Re: Knot testing - Life support knots - procedures and results
« Reply #45 on: August 22, 2009, 08:16:20 PM »
 :)   Here's a "bump" to remind folks of this thread, and Agent_Smith in our
continued interest in its development -- such as photos of tensioned knots,
and, of course, further data to chew on.

--dl*
====

agent_smith

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Re: Knot testing - Life support knots - procedures and results
« Reply #46 on: August 28, 2009, 08:28:32 AM »
Hello...I'm back again.

I have created a 'public downloads' page at www.paci.com.au (hopefully any traffic attracted to the site wont clog my bandwidth and cause me financial pain!).

From the home page, click on 'public downloads' and then the first 2 files you see in the table will be about knots.

I have given kudos to Derek Smith and Dan Lehman for their critical reviews of my work which spurred me on.

I consider the work good enough to open up to the public domain...and no doubt I'll receive some more feedback.

This site is all about giving back to the public and contributing to our collective knowledge on all things knots.

Some files are password protected...the knot study guide is 'thankyou' (without the quotation marks).


Mark

capt larry

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Re: Knot testing - Life support knots - procedures and results
« Reply #47 on: August 28, 2009, 04:05:21 PM »
Mark,

First welcome back.  I have been following this thread - though without posting since for me it has been a learning experience.

Personally, it has been worth the wait.  Your work is a fine contribution to knotting.

Have only had an opportunity for cursory review at this point but am impressed by the detail and clarity of your presentation, the illustrations are very well done.

One critical observation that popped out at me is in respect to the "Butterfly" - a favorite knot of mine.  As I read it, the knot was not referenced as ABoK "lineman's" and it was attributed to W&G.  A recent thread on this forum has shown that it was published  a few years before (1917) in a paper by Burger at Iowa State Univ.  Also, there has been a thread here where Alpiner showed an extremely easy alternative to tying it that seems to give easier control over the sizing of the loop.

Will be awaiting Dan L's reaction.

Larry   

roo

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Re: Knot testing - Life support knots - procedures and results
« Reply #48 on: August 28, 2009, 04:16:34 PM »
Hello...I'm back again.

I have created a 'public downloads' page at www.paci.com.au (hopefully any traffic attracted to the site wont clog my bandwidth and cause me financial pain!).


When clicking on the first file, I get a message that the file is damaged and cannot be repaired.  Maybe I can try again later with a different brand of reader.
If you wish to add a troll to your ignore list, click "Profile" then "Buddies/Ignore List".


Dan_Lehman

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Re: Knot testing - Life support knots - procedures and results
« Reply #49 on: August 28, 2009, 05:31:19 PM »
I have created a 'public downloads' page at www.paci.com.au ... .
When clicking on the first file, I get a message that the file is damaged and cannot be repaired.
Maybe I can try again later with a different brand of reader.

I just clicked on the URLink and after a long (dial-up:  about 6min?) period
in which things appeared to be in fact loading (modem indication, and the
locator-window URL text being gradually highlighted ("filling")), I ended up
with the browser window *done* and ... no sign of a file anywhere!?
-- no nastygrams, either; just no productive result, so far as I can tell.

!?!?

OH, this attempt was for the KNOTS (not Bowlines) file, as I was looking for
updated test data.  (Which it might be helpful to post to this thread in the
format of my previous summary update (i.e., w/o reiterating the tedious
detail of device/rate/attire-of-tester...).   "Just the facts"

--dl*
====

Dan_Lehman

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Re: Knot testing - Life support knots - procedures and results
« Reply #50 on: August 28, 2009, 06:13:49 PM »
One critical observation that popped out at me is in respect to the "Butterfly" - a favorite knot of mine.
As I read it, the knot was not referenced as ABoK "lineman's" and it was attributed to W&G.
A recent thread on this forum has shown that it was published  a few years before (1917)
in a paper by Burger at Iowa State Univ.  Also, there has been a thread here where Alpiner showed
an extremely easy alternative to tying it that seems to give easier control over the sizing of the loop.

Will be awaiting Dan L's reaction.

Capt.Larry, about the Lineman's Loop aka "Butterfly knot" aka "Alpine Butterfly",
what we have is a case where a knot was discovered in two separate places (at
not all so different times).   One can postulate that there must've been many other
like discoveries, but who knows.  (I was remiss in missing CLDay's note, and am
quite glad that Bob Thrun read more attentively, in addition to pursuing that lead
so well (and now having not only e-copy but also --courtesy a link from Nautile--
hardcopy of the earlier work.  (It was Bob also who had gotten W&G and put
it into e-form, which Charles Hamel has kindly put up on-line for access.)  And
we can reflect on the multiple discoveries --over a 2-3 decades-- of SmitHunter's
Bend:  Smith, Hunter, Lehman (and ... ?).  Despite Phil Smith's publication in
a book (limited circulation, but still ...), it was a "new" knot to many, taking
Edward Hunter's revelation via the Times & perhaps also IGKT-informed authors
to become more public.  (resp. circa 1955, 1964, 1973, for S-H-L, I think)
So, I think that W&G deserve both merit for discovery (not exclusive, but
authentic) and publication, and perhaps their efforts were what can be
traced into the acceptance by rockclimbers, and thus into other disciplines;
whereas, despite use & publicity, perhaps --I don't know-- the knot's life
waned in the lineman world (or can we find in then-current & following
years/decades published guidance for such workers to continue it use?) !?

And I concur in your assessment of Alpiner's (initial, at least -- were there two?)
improved tying method.  In fact, that was put out to some rockclimbers and
got a bit of a nod of approval; the other methods are simply not so neat.

And, now, I have found a sort of *brother* to the Butterfly, in which there
is one seeming superfluous wrap of one eye leg around the body of the
knot (whereas in the original the eye legs flow into collars; this extra
wrap is quite helpful if the orientation of eye loading can be foreseen, as
it fairly well prevents the (effective) end's collar from collapsing around
it -- i.e., in a case where one end is loaded (so is "S.Part") and the other
completely slack, the collar on the slack end has no resistance and can
be drawn tight around it, to the point of jamming.  (And I've discovered
a great many similar but "directional" eye knots, using a Slip-knot
base, as well as a #1408 equivalent to the Butterfly (which comes about
also with that eye-leg wrap).)

--dl*
====

postscript:  How Creation Works (one case)

I just conceived a **New & Improved** Directional Fig.8 eye knot,
led to such fancy by mulling over this topic and then the formation
from the Slip-Knot and so on.  Had to keep closing my eyes to "see"
this, to double-check that it wasn't illusory, and then to manifest it
in rope.  Ta-da!  doesn't look bad.

Partly what led me into invention was reflection on the CMC Rope Rescue
Manual
data in which the usual, Fig.8 eye knot tested a few %-pt.s STRONGER
in end-2-end loading than the Directional Fig.8 (!!)  -- quite surprising, as both
the former is deemed bad as a knot, and even too bad to even sustain pulling
by two persons(!), and the latter's raison d'etre is supposed fitness for such
loading (where, however, I've noted that it has the form of a SquaREef knot
w/one slip-tuck) !?  I think that CMC might've gotten lucky on their test,
and would love to know how their Fig.8 was dressed & set (since I believe
that those accounts of its failing to how qua bend --and here the only
difference is whether the eye is cut or not (irrelevant if holding)-- are not
jokes.  TMoyer's testing of the Offset Fig.8 bend (the so-called "EDK"-like form)
show it holding and not holding, variously; though it didn't seem strong.

(Hmmmm, now it occurs to me that this recent invention might be one
I have previously done  -- rather behind on recording, or if done long ago,
forgetful of it (or perhaps the knot form then came about not by tying in
the bight (or even if doing so not considering it for "directional" use),
and not being aware of the potential).)

((double-HmmmMMM:  Moreover, this variation of the Fig.8 is what
I think some rockclimbers tie as a sort of "backed-up" and easier to
untie version (and it might be more vulnerable to ring-loading),
similar to another such version.))

argh:  now it's getting to be work ...   :(

agent_smith

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Re: Knot testing - Life support knots - procedures and results
« Reply #51 on: August 29, 2009, 04:31:51 AM »
Thanks for the comment re Butterfly knot...am aware of the historical significance and am working on the knot study guide to update it asap. Will upload revised pdf file very soon and announce it on this forum.

To Dan: There does seem to be a glitch with the way Mozilla Firefox downloads and reads PDF files in the browser window. I tried clicking on the first 2 knot links in the table and they both 'froze'. I then closed Firefox and re-opened it and cleared the history. On second try it opened normally and asked for a password. I have no rational explanation for this strange behaviour.

However, an alternative way to access all the files is to right click and then choose 'Save link as' (for Firefox) or right click and then choose 'Save target as' (for Internet Explorer). The right click method always works with all browsers.

Make sure you are using the latest version of Adobe Acrobat Reader (we're up to Ver 9). Also make sure you are using the latest version of firefox or internet explorer... (just my suggestions).

Dan/Derek, I am expecting some serious critique from you guys...will take on board any comments and fix/update my work accordingly. I noted that you are silent on my EBSB variant Bowline! I was definitely expecting a few remarks re this alternative tie-in knot for climbers... (I have been using it for some time now with good success - always easy to untie after repeated loading events and is stable and secure). Learning to tie it is more difficult than the F8 eye knot, but nothing like a bit of repetition, repetition, repetition to sort out the long term memory issue!

I am also going to place more emphasis on the properties of knot security and stability (rather than pure strength). This will feature in my next update.


Mark

Dan_Lehman

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Re: Knot testing - Life support knots - procedures and results
« Reply #52 on: August 29, 2009, 06:16:45 AM »
Thanks for the comment re Butterfly knot...am aware of the historical significance and am
working on the knot study guide to update it asap.

To be clear:  the evidence so far is consistent with W&G originating the knot
for themselves (not sure how this would be disproven; have no reason to
doubt it -- they seem honest), and I surmise that by them it became known
in climbing circles.; beyond that world's horizons, however, it is clear that
the knot was known to others (who happen to have earlier dates of publication).

Quote
To Dan: There does seem to be a glitch with the way Mozilla Firefox

Safari here, so far.  (Though working w/Yahoo Mail is getting very annoying.)

Quote
I noted that you are silent on my EBSB variant Bowline!

I thought I'd lambasted that previously?!  This is the EBSB +Yo finish, yes?
(Fig.s #26-7 of pdf#6)
To my mind, it is gratuitously complex and suboptimal; you did have the Janus
Cowboy Bwl, and that is vastly simpler.  I just gave a token of that a good
load with the pulley, and the Janus C-Bwl looked good in S.Part curvature.

--dl*
====



capt larry

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Re: Knot testing - Life support knots - procedures and results
« Reply #53 on: August 29, 2009, 03:14:59 PM »
Dan,

Thanks for the info on origin of the "Butterfly". Don't want to contribute to further inaccuracies in the knot tying history.

Mark,

I use Firefox and had no problems. Should note that the second time I used your link and don't think I needed the password.

CL

Dan_Lehman

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Re: Knot testing - Life support knots - procedures and results
« Reply #54 on: August 29, 2009, 07:04:38 PM »
Thanks for the info on origin of the "Butterfly". Don't want to contribute to further inaccuracies in the knot tying history.

I should remark that much of the problem is our lack of objectivity in
reporting:  if we say "W&G invented the knot in 1928", or assert that
theirs was the first public presentation of it, we are saying more than
we have a right to -- or using "invent" in an arguably legitimate way but
without care that it can be interpreted otherwise.  So, saying simply and
clearly that, e.g., "The first-known publication of the Butterfly knot, so
far as the authors are aware, was in 1928 ..." is clearer; and, as Joop K.
remarked, is the unassertive way in which W&G themselves introduced
it -- as new to them though conceivably known elsewhere.

Further, note that we can credit W&G with invention (i.e., innovation
regardless of that done by others previously); we cannot credit Burger
with that, only of having published what he alleges to have found or
known about -- and so for the earlier emergence of the "Lineman's Rider",
we have yet to trace beginnings (one can wonder about some old
industrial manuals for linemen).  Similarly, re the Constrictor knot,
although we might believe that "Tom Bowling" presented it in his
old knots book, that he did so as almost an aside -- lacking an image
to correspond with the text, odd for the book (and as did, likewise,
Ohrvall (!! -- what is about this knot?!)) -- , in both cases the authors
seem to be merely conveying information known in some way and
not presenting a novelty originating with themselves.  So, there is
yet further tracing to do.

Btw, verbally:  if you tie the Butterfly by the old "twirly flop" method
--i.e., of twisting the line and then bringing the bight around to tuck
into the twist--, at the point immediately prior to this finishing tuck
if you give the one side that can do it a half twist (doing so for one
side will UNtwist it, for the other ... work), you will orient the two
S.Parts so that they draw into the knot in the same rotation (whereas
the Butterfly usually had one pulling opposite other, rotationally).
You will find that this line w/extra half twist forms a Fig.8 to the
other's Overhand; and it will be less able to jam if being the end
that is not loaded when the eye is loaded.

--dl*
====
« Last Edit: September 18, 2009, 04:35:57 AM by Dan_Lehman »

agent_smith

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Re: Knot testing - Life support knots - procedures and results
« Reply #55 on: August 30, 2009, 02:50:45 AM »
I have uploaded VER 4.0 of my knot study guide. It is now live and ready for download. Password = thankyou

Go here to access files: www.paci.com.au and then click on 'public downloads'

I have made amendments to the following areas:
[ ] Section on knot stability and security - warnings and emphasis that security and stability are of greater important than raw strength in human life support applications
[ ] Section on the Butterfly knot - added historical note re the AA Burger book published April 1917 and the reference to the 'Lineman's Rider'
[ ] Section on the Bowline - added information about alternative name (Right hand Bowline per Ashley)
[ ] Added acknowledgment to those who assisted me in preparing my work (eg Derek Smith and Dan Lehman)
[ ] Added information about copyright laws


I have also added AA Burger's work as a downloadable PDF file...


Feedback is always welcome.


Mark

« Last Edit: August 30, 2009, 03:35:42 AM by agent_smith »

dfred

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Re: Knot testing - Life support knots - procedures and results
« Reply #56 on: September 17, 2009, 06:48:39 PM »
I have uploaded VER 4.0 of my knot study guide. It is now live and ready for download. Password = thankyou
[...]
Feedback is always welcome.

I lost track of this thread at some point and was just catching-up.  The Knot Study Guide is looking great, here are a few comments:

Page 23: The strength section of the Zeppelin Bend reads: "...this knot is strong, but quite as strong as the double fishermans..." -- should this read "but not quite as strong"?

Page 29: The comments about Burger look good, however there is actually a slightly earlier publication date, August 1, 1914, for Rope and Its Uses.  Here's a link to that edition on Google books; note that it is embedded in a much larger collection within the single PDF document:  Rope and Its Uses, A.A. Burger, 1914.  (Direct link to page where description of Lineman's Rider begins)

Page 44: The name "Slipped Double Overhand Knot" seems like it could be misleading.  The term slipped often means the final tuck of the knot is a bight, so as to facilitate a quick-release.  In the case of a double overhand knot, this could mean that the slipped portion was the working end rather than the standing part.  It's a minor point and probably unlikely to cause confusion in reality, but have you considered using "Double Overhand Noose" for the primary name instead?  (I see you do mention "noose" in the alternate names.)

Those were the things that jumped out, but I'll keep looking through it.  I also have forwarded it to my cousin (not the one with the hanging tomatoes :) ) who is a climbing guide and instructor in the western US.  I'll let you know if he has any feedback.

Thanks for posting this and all those other interesting documents on the public downloads page!

Dan_Lehman

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Re: Knot testing - Life support knots - procedures and results
« Reply #57 on: September 18, 2009, 04:51:57 AM »
Page 23: The strength section of the Zeppelin Bend reads: "...this knot is strong, but quite as strong as the double fishermans..." -- should this read "but not quite as strong"?

As this document takes software (Apple's Preview doesn't handle it) that won't
be coming down the dial-up line anytime soon (IIRC, Adobe's latest is a load),
I'll be a while taking a gander.
For now, though, I think that the right question to the above text is "Says who?"!
And I made this point previously:  on what basis is Rosendahl's Zeppelin bend
judged to be "strong" (typically interpreted relative to others) ?  Beyond this is
the point to being strong vis-a-vis the intended application(s), which I recall
including abseiling -- where strength is irrelevant in the usual cordage for it.

Quote
Page 44: The name "Slipped Double Overhand Knot" seems like it could be misleading.  The term slipped often means the final tuck of the knot is a bight, so as to facilitate a quick-release.  In the case of a double overhand knot, this could mean that the slipped portion was the working end rather than the standing part.  It's a minor point and probably unlikely to cause confusion in reality, but have you considered using "Double Overhand Noose" for the primary name instead?  (I see you do mention "noose" in the alternate names.)

I believe this comment gives sufficient illumination to the issue:  the name I push
for this is "Strangle (knot) Noose (-hitch)".  (Yeah, a rather variable/optional name.)
The Strangle knot can be found, w/o confusion, I think; "noose-hitch" is a name of
a structure (vs. knot) which naming lends itself to comprehension (of a
structure that employs the named knot tied to its S.Part to effect the attachment);
and "Dbl.Overhand" can have more range, if left as a more topological denotation
(where the Anchor Hitch and Strangle are Dbl.Overhands; I've seen the former form
used qua stopper in Com.Fish.Knotting, btw).  (Chances of "Clove hitch noose"
overtaking "Two Half-hitches" is pretty slim, huh.)

Quote
Thanks for posting this and all those other interesting documents on the public downloads page!

Yes, much!

--dl*
====

agent_smith

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Re: Knot testing - Life support knots - procedures and results
« Reply #58 on: September 25, 2009, 04:12:11 PM »
Thanks for feedback dFred.

I have made amendments as recommended. VER 4.1 is uploaded to the site: www.paci.com.au (then click on 'public downloads').

Was unable to download 1914 ed of AA Burger book (Rope and its uses). Seems locked out to me here in Australia. Was able to obtain the 1917 ed was search through google but not by clicking on the link embedded in this forum. Would be keen to grab a hold of the 1914 edition...

Dan, I have changed the name to Double overhand noose (ABoK #409).

Also improved references to 'strength'. Made specific warning that stability and security are the most important features in life support knots.


Mark

Dan_Lehman

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Re: Knot testing - Life support knots - procedures and results
« Reply #59 on: September 26, 2009, 04:34:16 AM »
Thanks, Agent_Smith.  Do keep in mind what the title of this thread is about
(as we look for further progress on that).

 ::)