Author Topic: Possibly a useful new Bend!  (Read 234 times)

geoff@frz_mtn

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Possibly a useful new Bend!
« on: November 23, 2019, 06:20:28 AM »
Hello everybody!
I would like to share what I think is a new bend. It is so simple that you folks that really know
something about knots must have already thought of it, so please try not to laugh!
I was working on memorizing my knot list when I re-tied the old Reef Knot and was thinking
about how neat and elegant a knot it is and how sad it is that it is an unreliable bend.
Suddenly Ashley's words came to me: "There is unexpected virtue in a round turn..." and so
instead of the loop on each side I tied it with a round turn on each side.
Surprisingly after I had worked it tight it would not capsize and seemed very secure, although I
am sure it will jam pretty hard after loading.
Maybe in slippery rope like dyneema it would be alright.
So take a look at the pictures and see what you think, maybe someone with a test rig can figure
this out.
If it works well just call it "Geoffrey's Bend" if you would!
Geoffrey S Robertson

agent_smith

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Re: Possibly a useful new Bend!
« Reply #1 on: November 23, 2019, 06:28:55 AM »
Thank you Geoffrey,

I tied this in Sterling 8.0mm diameter cord.
It holds well - appears to be secure and stable.
With the reef knot (#1402), the tail positions matter... would be of interest to compare the addition of round turns to #1405 Granny knot and/or #1207 Thief knot.
In any case, the addition of the round turns (540 degrees) provides additional friction to bind the core. Core compression is maintained.

Can't comment about resistance to jamming... would interesting to test this.

Also not sure if your presentation has been tied before...always hard to determine originality - even long standing claims had been shown to have been discovered elsewhere.
Eg the #1425A Riggers bend... and we now think that Bob Thrun discovered the Zeppelin bend (unless new evidence comes to light).
« Last Edit: November 23, 2019, 01:27:33 PM by agent_smith »

agent_smith

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Re: Possibly a useful new Bend!
« Reply #2 on: November 24, 2019, 03:30:03 PM »
I have received notification from Xarax that he had already tied and investigated this particular 'end-to-end-joining knot' several years ago.
Link: https://igkt.net/sm/index.php?topic=4976.0

Xarax confirms that the knot jams.

The knot apparently has the name - 'Summer bend'.


Dan_Lehman

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Re: Possibly a useful new Bend!
« Reply #3 on: November 30, 2019, 06:35:34 PM »
I re-tied the old Reef Knot and was thinking
about how neat and elegant a knot it is
and how sad it is that it is an unreliable bend.
Suddenly Ashley's words came to me:
"There is unexpected virtue in a round turn..."
and so instead of the loop on each side
I tied it with a round turn on each side.

Except that your images belie this claim to being
derived from the squaREef knot --rather, one sees
it as following from the thief!
(Consider the orientation of the turns :
if taken as you say, one side turns away
but the other turns back-to ... .)

There are various versions of this structure,
depending upon the loading profile and the
dressing; I suspect that they will all share
the jamming quality (which can be a good thing
for certain applications).  One arrangement is
much like the grapevine --but tails run in the
opposite direction, going out the opposite SPart's
nip.


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Keystoner

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Re: Possibly a useful new Bend!
« Reply #4 on: December 07, 2019, 06:06:18 PM »
Xarax confirms that the knot jams.
Gosh, as much of a fan of knots as I am, I don't understand what it means for a knot to "jam."

Dan_Lehman

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Re: Possibly a useful new Bend!
« Reply #5 on: December 07, 2019, 07:28:32 PM »
I don't understand what it means for a knot to "jam."
"jam" mostly means "becomes un-untiable, stuck, 'welded'".

In more practical terms, it might not indicate
an all-so-problematic condition; it's esp. true
if the experienced loads are not so great.
Ashley's #1452 end-2-end joint has various
dressings, one of which can make it "jam"
--which can be "welded" under high loads,
but otherwise might be just the thing to tame
e.g. slick-springy polypropylene rope used
say for a dog leach.

Beyond this, one might want a "welded" tight
knot.  Anglers, e.g., aren't in the business of
untying knots.


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