"Ashley Bowled Over" & Re-tucked (#1452)!

[xarax]

  Regarding the 5 easy to remember ways to enhance the security of a simple bend :

1. Re-tuck its Tail Ends once more through the same openings they were tucked in the first place.
2. Retuck its Tail Ends through the central opening of the bend.
3. Un-tuck the Tail Ends once, drive them turn around the Standing ends ( so they make a 180+ degrees turn, a collar, around the Standing ends ), and re-tuck them through the same openings they were tucked in the first place.
4. Use the Tail ends to tie half hitches around the Standing ends.
5. Add 180 degrees at the turns the Standing parts make around each other.

The 3 can lead to the same knot as the 5, or not - and vice versa. The 5 in the case of the oSE C - oSE C, shown in previous posts, has not produced the "collared" uSE C - uSE C, The "Ashley s bowled over" bend.

[Dan_Lehman]

  Regarding the 5 easy to remember ways to enhance the security of a simple bend :

1. Re-tuck its Tail Ends once more through the same openings they were tucked in the first place.
2. Retuck its Tail Ends through the central opening of the bend.
3. Un-tuck the Tail Ends once, drive them turn around the Standing ends
  ( so they make a 180+ degrees turn, a collar, around the Standing ends ),
   and re-tuck them through the same openings they were tucked in the first place.
4. Use the Tail ends to tie half hitches around the Standing ends.
5. Add 180 degrees at the turns the Standing parts make around each other.

The 3 can lead to the same knot as the 5, or not - and vice versa.
The 5 in the case of the oSE C - oSE C, shown in previous posts,
has not produced the "collared" uSE C - uSE C, The "Ashley s bowled over" bend.

And these five can be found wanting, as you note
--that they don't lead from #1452 (and like knots)
to the "bowled-over" structure that seems to be
succeeding.  (Now, some knots might begin with this,
so we should amend the title of these rules from what
can be done TO a given knot for enhancing, to what
can exist IN a knot that will give it security.)

Some of the above Five seem to be a matter of somewhere
making a sort of *nip*; and this can be seen as simply
adding some more-of-the-same friction by means of
more area contact!?  And others add a U-turn, which
gives both frictional resistance, and also some resistance
via bending-flow.  Whereas with the bowled-over
structure, we are --what?-- not so importantly adding
real estate to create friction --though that IS done--,
but creating greater pressure/compression at the
central friction-generating, nipping point?!
--and that into this pressurized zone, we tuck the
last-chance-at-slippage tails for nip!?

That the ("merely" might we venture?) re-tucked
#1452 has the "last-chance-..." aspect but lacks
the "bowled-over" pressurizing (and its added contact)?!

Incidentally, we might *see* by means of fitting theory
to observation as best we get from EStar's nice pics of
the quadruple fisherman's knot slipping that the
draw of the S.Parts --here, though, it seems to be of
just one side, mostly?-- pulls the tail into the knot
from which it marvelously escapes courtesy of the
strong pull of force flowing so frictionlessly around
the core(!!) --AND it flows so *immediately*, because
of the near-nothing elasticity of the material : the
pull at point-A affects point-B immediately, lacking
the elongation of near-point-A material that in
other materials would give some delay.

I have to wonder if a properly tied blood knot
--or one w/simple re-tucking--
would hold, and to what benefit for strength
(none for untying!)?!  I'm appalled that I cannot find
on the bloody darn Net a presentation of the proper
tying and formation of this knot!!!!!  It should be
formed like the double harness bend --and, yes,
there are tails-together & tails-opposite symmetries--
but with many, full wraps --wrapping around both of
the S.Parts, TOWARDS the final, center tucking point,
not away from it.  @(*$&^*#&
(This system won't allow me to express my anger
at the Net echoes of stupidity!)
                                 

DFred, who's doing all the latest revising of Knots
on Wikipedia?  I do not have the time or presence
or number of fingers to go plugging all the leaks
of knot stupidity into our land!!


--dl*
====

[Dan_Lehman]

On this thread I tested the initial bend :  Strong and did not slip.
I also tested the bend in the pictures just above where I gave my test results.

Ouch, I'm getting dizzy zipping back'n'forth to find
apparent NEW information edited into OLD posts!
(A post beginning "I will test it tomorrow" sees me
looking AFTER it for the results, and only now do I
see that you did in fact test and did get good results.
My surmise on not seeing a clear response was that
you in fact got such good results to not have a knot-B
to rate it with (except as superior) and were pinging
EStar in order to try to calibrate the new high.  And
maybe so?     )

You got to be kidding, right?
 You posted a photo and I tied it.
What else could I be talking about?

Um, apparently a response to a now ghost post
which makes one wonder indeed what you are
talking about.  (The QUOTE button is your friend,
most esp. w/Xarax.)

Meanwhile, though, I'm surprised that there was
EVER any doubt that the fig.8'd #1452 would slip,
when the re-tucked knot did --the openness of the
fig.8 cries out "slippage!", no?  (Which fig.8 knot has
held, btw : the eye knot, maybe; but an end-2-ender
(loaded how : inner course, or outer?) ... ?)

Above is shown a version of the zeppelin knot that
should be most enticing, as it has the attributes of the
extended #1452 that look good, AND ADDS to those
the (we'll hope) ability to be UNtied after loading!
(As well as being easier to tie & recognize.)
(The ease of untying I'll hazard exits and comes
from less tight binding of a wrapped tuck around
the S.Parts' coil; it occurred to me to wonder if
that binding however in some way contributes
to strength, by pressure early on the S.Parts :
but I think that the slickness of HMPE just won't
notice anything but huge pressure,
and it can't be huge at this final-tucking point
or the tail would pull out!  .:. So, we shall hope
that the bowled-over zeppelin re-tucked secures
the whole boatload of desiderata for us!
[And isn't d. a delicious mouthful!    ) )

Maybe we're onto some firmer ground, at last!
And can also now remember to ask, What about
eye knots? --where I think one has reason to hope
for better results, as there is just the lone S.Part
to treat, and the rest of the knot can make more
compromises so to do this.  (And then we can ask
how eyes interlocked say with the granny structure
fare re strength --or maybe an extended carrick mat
for the eyes-joining structure, which should bring
thoughts of one of the (lengthy) eye knots favored
by anglers for the HMPE "gel spun" super-strong lines.)


--dl*
====

[allene]

Some various answers are below.

I actually did the testing about 10 minutes after I posted reply 1 so just edited it.  Sorry.

The figure eight that held was a loop, an eye knot if you will.

My last bend was sort of an interlocked eye knot although there was more to it that that.  The problem is that we knot that if you secure an eye knot to a ring and if that ring has the same diameter as the line, then you have lost about 1/2 line strength in the bend but as you also have half the load, you are fine.  But it looks like interlocked eye knots compress the line down to way below nominal line diameter and the structure fails there.  I produced a knot that didn't slip, but it broke before my first bend slipped so why bother.

I also posted a modified bowline that does not slip.  Seemed like there was less interest in it.  Estar proposed a kind of halyard bend that is very strong and does not slip.  But these knots are only strong around metal rings, not around other line. 

Perhaps I will delete my reply to the ghost post :-)  That should confuse people even more as it has been referenced.

Allen

[xarax]

I'm surprised that there was EVER any doubt that the fig.8'd #1452 would slip...
 ...when the re-tucked knot did..

  I do not understand what do you mean here, but I, for one, had not any doubts... I had posted this bend as just an example of a fig.8 ed Ashley bend, but allene has not understood this. After an exchange of posts, when the issue was settled ( I was as dizzy as you about the sequence of posts ), I saw no reason why I would spoil your thread with irrelevant posts - but you have not understood that ! 

  Have you made any experiments I had missed, which proved this new theory of yours, that a re-tucked knot, without collars, is always more secure than a non-re-tucked one, with collars - and so, if the re-tucked knot un-collared knot slips, the un-retucked collared one should slip, too ? If you did, I will be able to find it, I suppose, because, in contrast to you, I search and find things - and in contrast to me, you never post anything irrelevant, never ! 
 

 

[allene]

Odd. I can see it.  How about this one.   But if it doesn't work, just to to this page http://www.animatedknots.com/fig8follow/index.php?LogoImage=.&Website=

[xarax]

   I believe I know this knot, so I would nt need to see it dancing ! 
   Eyeknots are more secure than the corresponding "parent" bends, simply because they can slip in one, only, way !  So, the fact that this knot holds, while the much more convoluted triple fisherman s does not, is not such a surprize, after all...

[Dan_Lehman]

   Eyeknots are more secure than the corresponding "parent" bends,
simply because they can slip in one, only, way ! 

You are forgetting what was shown in the Brion
Toss video of the almost mirrored bowine --and which
behavior he'd reported on some time ago, in a
SAIL magazine article : that eye material can
slip through the knot and out ... the S.Part!

 

[Dan_Lehman]

Odd. I can see it.  How about this one.

Apparently a response to a quick remark from X.,
who --same with me-- saw only a blue box'd '?'
until ... it all loaded; I now see it, too --but maybe
my system is too slow for its "dancing"(!) (and at
the referenced site).  Thanks.

Now, note that the fig.8 eye & end-2-end knots
are often presented in the pure "flat" form in
shown by Grog before drawing it up (which he
did on my advice in that particular way --a way
that is not commonly shown or done, to my
observation : more often it would be the tail
of that orientation that is loaded!)

The end-2-end knot tied in Grog's-shown orientation
will tend to assume about a 45degree angle to the
axis of tension; loading the other ends will produce
a knot that is more aligned (and whose end-most
turns are lacking tension).  Thus, one can observe
photos of tied knots and get an idea of orientation.)

The figure eight that held was a loop, an eye knot if you will.

FYI, I've pushed "eye (knot)" because IMO "eye"
is more narrowly defined and should be understood.
"loop", in contrast, is used to denote the form of
line made e.g. as the initial step of tying a bowline
in the rabbit-&-tree manner, it is the thing formed
by tying ends of a line together (e.g. by EStar in the
end-2-end knot testing), or it might mean . . .
an eye knot!  Thus, I've tried to move away from
that overloaded term "loop" (which I now use mostly
for the first sense cited above; "round sling" can do
duty for the 2nd).

NB: The knot shown by Grog is symmetric; that in
your 2nd reference looses the form with its eye
legs falling out of the orientation seen at the
opposite end (where S.Part makes its U-turn).
(I think that torsion can lead to this if forming
the knot by working with a bight (doubled rope).)

Typically, only "fig.8" is given as knot indication,
and one is left to guess the geometry AND which
end is loaded!  No one seems to notice this point
of differentiation, though, but are often happy to
quote test results as though they're definite!

As for using eyeknots qua end-2-end structures,
there is the potential to interlock the eyes with
some structure such as a carrick mat or to
have each knot's tail complete the *eye* in the
opposite knot --the "twin <eyeknots>" structure.
(In the case of a bowline collapsing its *eye*
--in HMPE-- such a structure would see the knots abut.)

--dl*
====

[xarax]

You are forgetting ...
eye material can slip through the knot and out ... the S.Part !

   Right !
   I am always forgetting it, because it is so counter-intuitive... Things that I see only in video can not really be imprinted on me. I wish I had a proper laboratory, to see this with with my own eyes, to get a feeling of this miracle ! Now, it is just another piece of information my brain can put aside...

[estar]

Dan asked me to test the Ashley Bowled Over" & Re-tucked.

I first tested it bowled over but not retucked - it slipped at 680lbslbs (in 1/8" amsteel, tensile 2500lbs).

Then I tested it both bowled over and retucked - slipped at 825lbs (photos below).

I then tested a sample to slip, and stopped the pull and let it sit for 30 minutes and it then held and broke at 1305lbs, which is 52% of tensile, which is equal to our other best non-slippers (ESTAR and Polamar).

Note: the numbers above are the loop load/2

[xarax]

  e-star and allen-e, you are doing an excellent work, and we all appreciate it much more than you can imagine. The whole history of bends, especially those tied on very slippery and very strong materials, can change its path because of you. You have stumbled upon something that should have been addressed and possibly resolved years ago by the knot-tying community. However, if your work is not systematic and organized according to some minimum standards - and I know enough about this matter to tell that it is not - I am afraid it will run the danger to be less appreciated than it should, and even to be forgotten soon. You have been called by the Fate to play an important role. You can follow this call, or not, it is your call !
  I have said it many times, and I will repeat it, because I love knots, and I try to ignore what knot tyers think=believe about each other. Start from the best, more comprehensive book/collection about knots we have, the "Symmetric Bends", by Roger E. Miles. Do not read the mathematics of it, although I understand that e-start, at least, can do I, in just a few hours. Start right from page 78, and finish at page 98 - 20 small pages with 60 clear tying diagrams, of about half of the most simple bends we have. Start testing them = collect the data of equivalently prepared and repeatable experiments, on Dyneema 1/8" ( or 1/4, if you have the equipment), say, three times each. When you finish, proceed with 3 more tests of half of them, those which slip and/or break at higher loads. Then, do it again and again and again. You will end up with 4 bends, and you will have turned the first page in the history of bend testing on slippery and strong materials.
   ( And, please, use International System of Units, which, contrary to the Queen s orders to Her Majesty s subjects, does NOT contain libs !  )     

[allene]

Dan asked me to test the Ashley Bowled Over" & Re-tucked.

I first tested it bowled over but not retucked - it slipped at 680lbslbs (in 1/8" amsteel, tensile 2500lbs).

Then I tested it both bowled over and retucked - slipped at 825lbs (photos below).

I then tested a sample to slip, and stopped the pull and let it sit for 30 minutes and it then held and broke at 1305lbs, which is 52% of tensile, which is equal to our other best non-slippers (ESTAR and Polamar).

Note: the numbers above are the loop load/2

I wanted to put these results in the context of my first bend.  The bowled over and retucked knot slipped at 33% of line strength.   This is essentially identical to the result with my first bend at 32%.  But my first bend can be untied.  The first bend variation, which cannot be untied, did not slip and broke at 39%.  My first bends are also smaller easier to tie knots.

Allen

[estar]

For my part - we have already found a 'bend' that never slips and breaks at about 50%, and which is relatively easy to tie - which is back to back estar's.  It's only weakness (in my mind) is that it cannot be untied.

So, in my mind 'the search' is for something either easier to tie or which is a no-slipper that can be untied.

 But honestly, the only real practical application (on a sailing boat anyway) for bends in bare dyneema is to make fixed loops which are too short for an end to end splice, and un-tieing is really not all that critical feature for those.  More important is low profile compactness and the back to back estar scores decently on that.  So, practically speaking I am happy with the solution we have already found.  I am skeptical that we will find a better practical solution for this application, but if we do, I expect it will be more along the lines of the long low profile fishing bends (like the blood - Dan I would love to see some pics of what you consider "right" for a blood)  than the shorter/rounder general rope bends.

By the way, one comment on testing these knots . . . the slip load is very hard to quantify.  It has a high variation, and in many knots varies quite a bit depending on pull speed. As I have said before, I am really only comfortable rating slippers as low/medium/high, and not very comfortable with the load specific numbers (which you all want). To get good (statistically understood) slip numbers I would have to do a minimum of 10 pulls (and 30 would be better), and have a mechanical very controlled standard 'pull rate'. I am not going to do 10 or 30 pulls times a whole range of knots simply because of the time and cost of this line . . . and I am not going to build a precisely controlled speed puller. For no-slippers, the breaking strength by comparison is easy to measure with low variation and high repeat-ability.

I guess we will all have our favorites.

Here's a pic of back to back estar's, which I did this morning just as a control for the Ashley bends, it is just about to break at 52% (the 95% CI is 50--55%):

[xarax]

... 'the search' is for something either easier to tie or which is a no-slipper that can be untied.

 Or for something that breaks above 50 % ? How do we know that the 50% is the maximum we can achieve ? Easy answer. We do not.

...the only real practical application (on a sailing boat anyway) for bends in bare dyneema is...

  One thing we should NOT take for granted nowadays, is what will be the practical application of whatever in "a sailing boat" - sailing boats are vehicles, they do not remain the same ! Unless somebody can claim that the mechanism used to adjust the inclination of the fully submerged foils in the America s Cup sailing boats last year were foreseen by anybody !   
  Noope, nobody can predict which the practical applications of a knot will be - and one GREAT example of this is the use of the reef bend on the tube of a bicycle !  (1). We do not want to learn about knots, because we have a fixed idea about a fixed mechanical problem of a fixed mechanism which we want to solve with a knot... We want to learn about knots because we like to do it - and because knowledge is a the most practically useful thing the Universe has created ! 

1. http://igkt.net/sm/index.php?topic=4762.0

I am skeptical that we will find a better practical solution for this application, but if we do, I expect it will be more along the lines of...

  Expectations should be based on adequate experience, and nobody has adequate experience with bends tied on such material. Of course, if you had discovered the wheel, you could be sceptical about better practical solutions, indeed !  However, there are HUNDREDS of back-to-back-hitches /nooses that have not been tested by anybody, for example. And, of course, HUNDREDS of re-tucked simple bends as well. I admire the boldness of the scepticism of somebody who believes that something will never be improved - but I trust more somebody who does not believe in beliefs...  

 

many knots varies quite a bit depending on pull speed.

  Among other things. Alternating loading should also be considered. The force by which the bend was pre-tensioned in the first place, during its dressing, would also play a role, IMHO. So, one should always pre-tight the bends he is going to test with a certain, always the same, load.
  I think that nobody yet has been convinced that the bends tied on thin and thick lines will behave the same way - although I, for one, hope that this is the case, indeed, and that the mere scale of the ropes we test will be irrelevant, provided all other things remain, proportionally, the same. JP has reported some results, but he has not repeated them on thicker lines.