Author Topic: Binders -- Various Tasks, Various Solutions  (Read 5028 times)

Dan_Lehman

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Binders -- Various Tasks, Various Solutions
« on: August 24, 2009, 08:33:30 PM »
Among the problems that cordage can solve is the binding of some
collection of things into a unit; this can range from the holding intact
the end of a rope (to preclude its raveling (and its unraveling!)), the
joining of things to each other (a sort of cordage stapling or gluing),
and holding multiple items together and possibly to some other object.

Among the binding knots presented in knots books are various
Miller's knots (bag closures) and the Strangle knot, as well as --since
Ashley publicized it-- the Constrictor knot.  Among the tasks for which
such structures are put to work are whipping rope ends, seizing ropes
together, seizing (or lashing -- a terminology issue) rope to something
(of vice versa) or non-rope items to each other, securing netting to
headlines & groundlines, and holding together some collection of
objects (such as gardening debris --sticks, et cetera) together.

Some of the aspects of binding structures to be considered are:
1) ease of tying;
2) consumption of material (material efficiency);
3) security of the binding;
4) dependence upon the bound object for security in/after tying;
5) ease of loosening/untying;
6) provision of force amplification (mechanical advantage)
7) likelihood of impressing the neighbors ("new"ness)

What others (I might have run dry after a half dozen  :D ) ?

In a recent thread in Practical Knots, a variation of a Clove Hitch was presented
as a means to move away from dependence upon the bound object(s)
for security -- the knot provided its own security, even if binding air.

I have seen the Constrictor presented for binding lumber together (i.e., some
squared material with four flat side surfaces), a task to which it is entirely
INappropriate -- but, no matter, a pretty picture was published in a knots book.

Attached is my revision of what Budworth has presented (citing some Girl Guides
book) as a "Pole hitch/lashing"; but that original lashing amounted to simply
a basis upon which a Reef knot was tied; it provided multiple wraps around
the bound items, but not a good way to hold the tension while tying.
This is what I sought to do in revision.
NB: the two-colored cords are for illustration purposes; they are bent together
behind the boards in the center wrap.  -- essentially, a single cord (as is the orange one).
NB':  Tensioning this structure puts more into the center wrap -- which as you
see is loaded from both sides -- than in the outer ones; one way to eliminate
this bias (vs. just living with it) is to make a full turn centrally, which takes more
material and effort.

I consider my revised binding a sort of *Paul Bunyan* structure, in that it
likely is costing more force per tension gained, contrary any apparent signs
of MA (mechanical advantage); but it pays off in locking in the gain (and
in impressing the neighbors!).  It should be noted that if one tries pulling
the ends in the opposite-to-photographed directions, hoping for some
kind of cheap 2-to-1 MA, what will often happen is some slippage of the
wraps around the object(s) -- the knotted part will close more, but the
apparent gain will be illusory re tension increase.  Note how the ends
are reeved through the nipping opposed-bights:  this is done so as to
better keep the ends from sliding out of that nip, which they are otherwise
prone to do (and might yet try to do even so).  To untie this tightened
structure, pull an end (one will do, as the lock is a joint effort) under
a bight leg to then force it out of the nip.  (E.g., in the case at left,
with blue & yellow cords, take the blue end (this is NOT a "bitter" end;
in fact, it is quite happy) out leftwards beneath the left leg of the
lower bight of yellow cord, then pull sharply up towards the darker
boards.)

 - - - - - - - - -

The opposed-bights locking mechanism can be employed in other ways,
and one way I found easier to implement (in fine monofilament fishline
to bind closed a deteriorating plastic car key-&-mini-light housing) uses
an eye in one end (still not "bitter") to re-direct the free end into interlocked
bights formed in further wrapping.  (verbally, now :  eye wraps around 2/3
object, u-turns forming opposed bight and wraps a full turn to put in an
opposed bight in this 1st bight, then connect through eye and back into
the tight-nipping opposed-bights to finish; haul end both directions!? )

--dl*
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« Last Edit: August 24, 2009, 08:44:18 PM by Dan_Lehman »

stebold

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Re: Binders -- Various Tasks, Various Solutions
« Reply #1 on: March 31, 2010, 10:50:59 PM »
A neater solution than the rather haphazard Pole Hitch that maintains a lot of tension, very nice!  I'd say you succeeded.
Another advantage I see is that you can loosen up your "Lumber Hitch" using the untying method you described, slide out a board and retighten the hitch.  With the Pole Hitch you have to completely untie the reef knot.

Sweeney

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Re: Binders -- Various Tasks, Various Solutions
« Reply #2 on: April 01, 2010, 04:46:51 PM »
I missed this when first posted which is a shame as I could have done with it. Sitting next to the PC with a piece of 5mm nylon braid I tried it around a stack of 9 CDs in jewel cases - worked a treat and that is an awkward parcel.

Barry

Dan_Lehman

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Re: Binders -- Various Tasks, Various Solutions
« Reply #3 on: April 02, 2010, 09:00:56 PM »
[Hogofogo's post doesn't belong here; it's a separate question,
which I think might have some kind of extant-thread answer, to boot! ]

The pictured binder is kinda neat, but also a bit cumbersome to effect.

Here is a related one in which one works with a single end, the opposite
tied into an eye.  Consider that the upper-left yellow strands wrap back
out of sight in to an eyeknot.  Then this eyeknot's SPart emerges at
the bottom as the center/blue strands to form a bight (which being
absent any engagement w/other cordage now will have to be held
in place), and then the end runs back as does the blue end to emerge
from the top down through this blue bight, making the eventual
nipping structure, and up through the yellow eye, and then is
reeved through the (blue) opposed-bights nip as in the original.
Thus, one has just the one end to haul upon, which in turn gets
that sort of 2-to-1 pull in the yellow eye.

And trying this now in new (virgin) nylon 16-strand hollow-braid binding
cord (as used by commercial fishermen esp. on binding netting), which
becomes flat, like a thick webbing, I find that one can pull on the end
in BOTH directions w/seemingly good effect.  (One does need to beware
sometimes illusory gains --where although there seems to be tightening,
it actually is a fair amount of cordage slipping around and the knotted
parts just collapsing without tension gain.)
Here, actually, pulling against the bight (not eye) does the
better job of imparting tension equally to the two binding wraps.  But
such hauling has some risk of pulling the nipped end out from being
nipped -- something one might be able to manually resist with a hand
against the nipping point to hold parts in place.

 - - - - - - -

One could try working a TurNip into this mechanism, where the point
would be to have that nipping structure in a position close to the hauling
force and so sooner affected by it (i.e., not being a full wrap-around-objects
removed from input of force on the ends).  But I find the nip given by the
opposed-bights to be good & sure, more so than from the TurNip.  (But
here's a way:  vice the eye above, see the yellow cord has in fact having
an end (as it does in photo), which end will come up from the bottom left
and go through the TurNip.   The other end will be as just described,
making the lower, blue bight, and after forming the opposed-bight in this
blue bight will have a TurNip in it en route to u-turning through the yellow
bight; then it and the yellow end will pass through the TurNip as done in
the Gleipnir.  Hauling on the blue end will deliver force to the TurNip
with just the u-turn friction at the yellow bight, and will be the main
tensioning action, with pull on the yellow end just resistance for it.

--dl*
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