Why so many turns common in fishing knots?

[KC]

What is the engineering reason;
for so many turns common in fishing knots and bends?
i kinda have my 'pure inline' mantra as theory..

[pspiering]

Purely my guess, but I would suspect that many turns are needed due to the low friction inherent in common fishing lines. Combined with the low diameter, the knots are more likely to slip. Adding more turns provides more friction and less knot failure. As a fisherman, I recommend the palomar knot as the strongest and most reliable.

[Sweeney]

What is the engineering reason;
for so many turns common in fishing knots and bends?
i kinda have my 'pure inline' mantra as theory..

Fishing knots are normally tied in extremely slippery, often springy, line with a relatively low breaking strength. The object of multiple wraps is to build up enough friction to limit slippage to that needed to trap the tag end and then lock. Fishing knots depend on some slippage to be dressed properly so it is normal to lubricate a knot before tightening (with saliva usually). As the line can easily be broken the knot must retain as much as possible of the line strength - not normally a consideration with rope. It would not be considered sporting to try and catch fish weighing say 1 lb or so on a line with a 30 lb breaking strain!

Sweeney

[Dan_Lehman]

Purely my guess, but I would suspect that many turns are needed due to the low friction inherent in common fishing lines. Combined with the low diameter, the knots are more likely to slip. Adding more turns provides more friction and less knot failure. As a fisherman, I recommend the palomar knot as the strongest and most reliable.

Interestingly, a knot that lacks all of the questioned
extra turns, and which really puzzles me at being so
strong --or, if so, at being remarkable/uncommon in
being so-- : for the line in it runs straight through the
knotted part (it's a noose-hitch) to turn around the
ring/hook, AND THEN comes the hitch-knotting.
I'd think that, given the U-turn around the hook eye,
most any reasonable securing would yield like results
to other securings, as some force would be spent on
the initial U-turn.  !?

--dl*
====

[KC]

i always looked at Palomar as kinda unique in some ways to this, but at same time perhaps just further step in evolution of same theory. 
.
Because by passing byte thru eye of hook, we are providing 4 potential legs of support, not just 1 to hook.  Perhaps some of the secret is in partial load sharing amongst more than just the S.Part of these members; to keep less load feeding thru primary loaded bend from 'pure inline'.   If OH above hook gives fair support to working end, bite goes thru hook eye, then comes up again to once again nip down on OH area securing 2nd 'leg' of bite going thru hook eye more, and the bite passed thru hook eye as well.
.
i've also always thought that working a RT over hook(after bite thru eye/wow sounds painful!); then work around S.Part could also be better, but 'rules' mite change in monofil for this; or it might have enough of same type of support effect going on; as to not be significant 'upgrade' to RT.
.
i think a real lesson from Palomar is that the OH in bight doesn't impact 'relative capacity' (as opposed to absolute capacity) as much as would expect from just bend thru hook eye.  i don't think an OH in single line/not bite would fair as well for capacity of line segment(sharper bend) as well as bite, also/added factor, bite gives more legs (4) to hook eye that normal (2).  Then perhaps gives enough grip where the 'other 3' can take some load off of direct hook support by primary from S.Part unloading that bend some(?).  i keep coming back to this same model..

[Dan_Lehman]

i always looked at Palomar as ...

Firstly, on >>looking<<, note that the knot is shown
in different orientations by various authors : Sosin &
(Lefty) Kreh pointed out that the bight end being
brought around the contained hook to the knot
should NOT be taken all the way back beyond it
--which puts it as a collar, making a pile-hitch noose.

• Budworth seems to have had this latter formation
  in most (but not first) of his many books;
  
  
• Pawson OTOH, is balanced via his earlier (1998) Handbook...
  and later (2001) Pocket Guide to ... this by showing the bight
   finishing around the hook in the latter or just past it but not
   past the knot collaring the ends (as does Budworth); but his
   tying instruction in the former doesn't include setting with
   the "tag" end --thought the step's image shows this--
   and wouldn't naturally lead to the pretty image of a tied knot
  
  
• Sosin & Kreh's 1972 edition says to be "careful that the loop
   [bight] slips past the eye of the hook" in setting (though the
   photo of finished knot looks rather ugly in the bulge this
   just-past-hook_eye bight-wrap looks), their 1991 2nd edition
   lacks such advice although its tiny image of a tied knot matches
   --one must scrutinize w/knowing eyes though to realize ... --;
  
  
• Peter Owen's (for L.L. Bean) Outdoor Knots Handbook gives
   the just-past-hook_eye image --should one be attentive to
   heed this, as verbally "seat the knot correctly" is typically
   unhelpful, lacking specifics re "correctly";
  
  
• Geoff Wilson's Encyclopedia of Fishing Knots & Rigs has
   only an image that suggests the NOT-past-hook_eye form,
   and no verbal guidance other than to "pull tag end and leader"
   --which is no assurance of a particular form, depending on
   circumstances of line & object;
   BUT
  
• in his Guide to Rigging Braid, Dacron, and Gelspun Lines,
   in presenting the triple palomar --where one makes
   a trio of turns of the bight through the hook_eye--,
   he does expressly advise to be "sure the loop in the doubled
   line continues to ride up over the eye of the hook and does
   not slip down and bind on the shank below the eye" --the
   most specific guidance I've seen
  

Because by passing byte thru eye of hook, we are providing 4 potential legs of support,

But in order to realize that potential, one must somehow
split the load on the S.Part onto these other legs --an
eye knot does this, but at the cost of the friction/etc.
within the knot, the bending (or gripping) of the S.Part.
How does a pile-hitch noose --or whatever that the
particularly tied "palomar knot" becomes-- achieve this?

MY SURMISE is that, for fishing knots in light-for-humans line,
the setting by loading "tag end" and so on can impart to
the structure some curvatures at a relatively high force
which thus persist at expected load ranges; whereas with
rope being so much stronger than human effort can likewise
set, the relatively high-vs-setting forces that come in
normal (and testing's much higher) loading enable the
S.Part to easily push aside such apparent deflections ... .
Rope e.g., visibly diminishes in diameter in many materials
under strong load --I recall remarking at this as mooring
lines for the CapeMay-Lewes ferry were mechanically tightened!

I hope that folks take from the above examples just how
poor is the state of knotting literature --how very much
the literature is lamely a matter of weak-to-strong copying
of others, errors & all; of how lacking is guidance and one
must presume understanding --all the "set properly" without
a hint of what that might be, and so on.  Typical of angling
knots literature is step-wise tying instructions accompanied
by diagrams that culminate in an indiscernible squiggle for
the completed knot --the author & illustrator likely had no
clue as to what should result : that might never have been
fully understood (though maybe in some cases would be
the probable result of tying just-so in just-this) !  !?

i've also always thought that working a RT over hook(after BIGHT thru eye/wow sounds painful!);
then work around S.Part could also be better, but 'rules' mite change in monofil for this;
or it might have enough of same type of support effect going on;
as to not be significant 'upgrade' to RT.

Oh, you're right.  And Wilson's latter book (w/"gelspun") doesn't
present the (plain ol') palomar but the triple, as noted, so
you get that splurge --though here I must caution that for some
(many?) line & eye combinations, there isn't adequate room
for 3x2 = SIX diameters (which would maybe occupy, in clock
terms of a noon-centered attachment side, an arc of the
ring from 10:30 .. 1:30, or wider, or have to double upon
itself --line upon line-- in some hard-to-specify-reliably way!?
As for the regular knot, Wilson has appendix testing report
that gives it "76%" where top knots show "130%" or so
--of rated/nominal tensile strength (which he remarks shows
that the line is way underrated (which is done so the maker
can advertise high strength when knotted --what a joke!))

THIS is the state of the art for knotting, folks.
Open your eyes/mind!


--dl*
====

[KC]

Once again humbled by all you present;
Thanks i thought i'd seen Palomar around hook shaft, and would think more proper to theory as so;
but fishing isn't my thing, just darn good examples of extended theory i think.
-i only found off hook /above eye Palomar's before posting..
.
i think we are on same page of examining loading from eye perspective for 1 view/checksum of other theories;
And a single/simple Turn just bends the S.Part generally, and decreasing relative capacity/less threads working.
Advance this to an RT or any other capture, that changes the support in eye from a J-hook /S.Part only, to more towards a cast eye bolt structure of shared support of multiple legs(usually 2, but Palomar has folded bight)) to decrease primary loading going to primary deformity/bend  vs. resistance to Bend (that schedules how many threads are working on the given reduced load).
.
But, what ever comes back and fixes to S.Part as primary bending of most fully loaded point/line to do this can't impact/bend more than saving by strategy. So, Bowlining back to S.Part would give more legs to load support, but Bowline then becomes primary deformity to highest loaded and minimal leg (1)  in game of monitoring retained/relative tensile capacity vs. absolute tensile/capacity as barometer.  This is where besides long 'inline' splice internally; next best is same externally in coils etc. for least loss to deformity on ave. to shared loading.  Simple/single Turn or even RT upgrade but partial /buffered by too much previous friction loading give slip not grip/ so effect is lost.
.
i think we can get partially or fully shared support from upgrade of simple/single Turn around S.Part
to a Full / Round Turn (i want to make simple Turn sound 'cheap' hear..) to give hold power on S.Part like on spar!
.
UNLESS (important dLehman lesson showing weakness/ but then proving mechanics) you have a RT around hook etc. before RT around S.Part, removes this effect.  (insert light bub smiley/icon here)
i think the RT around S.Part needs enough force flow/ line tension to do the trick, because it needs to grab S.Part hard enough to give support not just slip. 
.
OR other strategies that approximate same with minimal deformity to fully loaded S.Part in trade.
Including, setting a point with OH, then perhaps having single or dual (like Palomar) support legs capture above shelf
Anything that gives more towards braided eyelet of support w/o deformity of primary support for 2nd support path for force flow
.
i think fishing knots just emphasize this even more because weakness in bend from 'pure inline' is emphasized, so offers this magnified view as well; without the reading glasses.  Especially in the not right angle pulls down the column of the line, with friction hitches in between both worlds, but point of examination that shows consistent with theory straight across.

[KC]

When tying a working knot;
i always think in models to dress/groom the structure to for strength and wear.
Even if tweaking the last drops of rope capacity isn't worth it in some cases;
the checking of your work and familiarity gained of knotting,
is in itself a real payoff when dressing out a lacing.
(this includes making sure line lays relaxed as possible/ not tourqued when unloaded)
.
One of the my guides is a rope clamp model,
A: Simple / Single Turn deforms from pure inline / some usable strength loss
B: Full / Round Turn >> deforms line and hugs around from all sides
C: Coil >> deforms line and hugs around several times to secure a segment of line


.
Given that a RT and Coil manage the deformity better / for less usable strength loss;
only if rope tension is flowing thru the turns / hard grip>>
i think the grip logically allows better management of the deformity by some or all these strategies:
1> load sharing like an eye splice to partially unload deformity
2> stabilizing deformity by firming grip
3> spreading SAME deformity out to LARGER area, for less impact per inch
(like angled/longer path across RR tracks can be smoother/less immediate)
.
Coil would  spread wear out over larger area and possible strategies it uses:
4> more load sharing to larger section of SPart
4a>section of line more pure inline with rope than single point grip of RT
5> firming and modifying larger section of deformity for less impact against usable strength
.
Adjustable Hitch, fishing knots, friction hitches  etc. seem to exemplify this model to me.
Palomar grabbing shaft of hook as de-scribed fits model better by grabbing a section of line;
 to shaft and load transfer there, rather than all at the sharpest bend/180? turn of sPart.
.
Model applied to bends of lines together would seem likewise,
would want load transfer thru turns/coils to sections of line(for 'purest inline' modeling;
not so much load transfer thru:
>> the sharpest bend/deformity 180degree+ turn at end of line direction /before turns on self
>>to single point

[Dan_Lehman]

Spydy, this model imagery isn't helping (me) !??   

 

And, again, re angling knots, one must remember that for
most of them there is a (IMO) key specification different
than for *rope* knots : setting (force) --for rope, humans
lack the ready means to make equivalent forces.
(Though, as noted, apparently for some stuff there is
a lessened need for wraps, apparently irrespective of setting?!)

And the Palomar is something I'd really like to see
scrutinized in comparison with some other knots --some
known, some maybe invented just to be like it.  For it
sure looks to my eyes like a quite non-extraordinary
knotting, and one where full force should be delivered to
the u-turn around the object (hook ring), after which there
just isn't much happening that could be asserted to be
what makes a difference!?


ANNND, given that imagery with 1-2-3 U-clamps (where the
U-part vs. its base should be what bites/compresses into
the tail end, not SPart),
I'd like to see further study of such terminations where
one arranges for there to be slightly diminishing tension
(or, if none, really, then increasing slack) in the tail ::
the thought is this : let the away-most binding be last
to take tension, as it makes first impression on SPart.
(And if it were a 100% efficient binding, and thereby
split force from the single-SPart strand into its
continuation and the tail, how could other bindings
matter?!  --my thought : arrange for this point to be
more a 70/30 split; the next binding to come 55/45,
and then 50/50!?)


--dl*
====

[KC]

Sorry i missed this.
.
Trying to show any bend/deformity weakens(Turn),
some strength back if gripped, not just bent(RT), even more if successive grips(Coil).
Some theories why.
Isolate/sift/rinse and repeat until nothing but simple truths persist thru all examples.
Then start all over backwards/cross-verify as checksum; like we do anything else.
.
i labeled SADDLE in drawing to fit my mnemonic ;

have always and all ways placed saddle to main/live/load side;
since being 'abruptly corrected' by an olde, screaming farmer,
and pedaled my sorry butt home 10mi./too young to drive.
Dad(harder to work for than farmer)had a hardware store, so found proper names, made  mnemonic,
so saddle labelled in pic!
.
Further, staggering clamps is even seen as wrong, so this is very specific.
http://navyadministration.tpub.com/14067/img/14067_70_1.jpg:

.
Gradual reduction of clamp tension is fair point and doable if can get test site.
Should be site for testing with metal components/shrapnel not just soft rope.
Target : isolating real-life knot function components,
and be able to alter outcomes by changing single variable.
Seeking: Is it just the way the line lays;
that later maintained strengths/relative capacity or the pressures and alignments!
If saddle tests pairallell real knots or not give paths to follow.
In any case, these are the models in my head that i lace and check all with;
and they do server well to calling care to proper crafting of knots;
even if not 100% accurate at each turn.
.
Can we approximate, alter and study thru '3rd party assets'
to isolate just what secrets are there all the time; that we aren't catching!
Is it the grip pressure, that is not given in simple/single Turn,
that manage the deformity better, leaving more usable tensile/strength/relative strength?
Or are their still other internal rope secrets defining these things?
.
If you make a rope eye with staples/pins(an earlier knot model) or clamps it shows very strong.
If just 1 pin/staple or clamp on rope eye, would seem more likely to deform/weaker;
several pins or clamps seem to do better job. 
To pure inline theory of strength, this would seem to be from a series of rope points;
being more purely inline than a single point.
.
Another similar item i always thought would be interesting to test:
Can we increase the 'strength' of a Single.Bwl. to approximate Dbl.Bwl.
by placing right size dowel in where 2nd ring/Dbl. would go(might need bed carved to give truest profile)?
Does just the changing of the arc of sPart over dimension of 2 turns give/refund the added strength/capacity?
.

[Dan_Lehman]

Gradual reduction of clamp tension is fair point ...

But wasn't mine :: I wanted "diminishing tension
(or, if none, really, then increasing slack) in the tail"
(which might be hard to effect w/steel cable, wire rope).
Conceivably, staggered clamp tension might have some
similar effect --allowing slippage at higher loads which
would then give the imbalanced tension(s) I want?!
(But likely too tricky to do practically --to know just
how tight ... !)

Derek did try this with seizings and thin polyester cord,
and his lone test seemed to confirm my point, though
it got slippage and not reduced strength, per se (IIRC,
he only tested to a tension in which differences obtained,
not to rupture).  I'd had some disagreement w/Brion Toss
about Brion's advice (IIRC, and which I'm not currently
able to cite) to put on seizings for a rope splice by starting
at the eye side and working out (IIRC),
AND increasing tension --on both tail & SPart-- in doing.
MY thought was to work eye-out (and I guess with highest
used tension, whatever that might be, initially), and then
to slacken tension on the tail slightly as one put in the 2nd,
& 3rd (& 4th?) seizing.  In this way, at the SPart side, the
SPart would do most work and only begin much drawing
on the tail after some initial elongation; for the next, inner
seizing, these two parts would be more evenly sharing the
load, and at the eye side it should be about equal.
Otherwise, I see great imbalance at the SPart side where
it would be 50-50% from eye going via seizing suddently
into 0-100% :: all force transfer occurring in THIS seizing.
(In practice, good seizings for safe loads are probably both
ample and slightly giving a bit of imbalance!?  I.e., it's not
as though we're seeing problems, though I don't know what
sort of test results there are for the structure --what possible
improvement is left to be got.)

As for fiddling w/dowel & bowline vis-a-vis dbl. bwl. and
strengths, I think more is to be gained by attentive testing
of actual things, first!  At this point, we can't even be sure
of there being any sure difference here; and images of what
geometry is in effect near rupture might inform us better
than making some change via dowel ... .


--dl*
====