Author Topic: Reverse Sheet Bend  (Read 2081 times)

jarnos

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Reverse Sheet Bend
« on: October 20, 2022, 04:58:14 PM »
Imagine a regular Sheet Bend. Switch roles of working ends and standing ends. Is there some common name for such a resulting bend?
Jarno Suni

jarnos

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Re: Reverse Sheet Bend
« Reply #1 on: October 20, 2022, 05:22:29 PM »
Oh, I found out that is called Lapp bend.
Jarno Suni

Dan_Lehman

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Re: Reverse Sheet Bend
« Reply #2 on: October 21, 2022, 09:11:04 PM »
Oh, I found out that is called Lapp bend.
But what you haven't found --but it should be broadly known--
is the simple *doubling* of this knot, following the old maxim
"One good turn deserves another" :: take the tucked Tail around
for a 2nd (maybe more) wrap & tuck, so to give a good grip on
the S.Part for slack-security.  This well distinguishes the knot
from the not-so-slack_secure sheet bend (doubled or more).
To loosen such a knot, pull the U-fold ends apart which should
prise out a LITTLE bit of S.Part, sufficient to work loose the
knot from there.

The Tail can be further tucked out through the turn made
by its own material.  At some point of tying to a larger
rope --i.e., with increasing difference in thin-2-thick--
one will lose the Lapp bend's points of security (the pressure
of U-fold apex against the tail, or of the further-tucked Tail
against too large a U-fold's legs, being thus loose within
the cavity between them and the turn of the thinner material).

--dl*
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KC

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Re: Reverse Sheet Bend
« Reply #3 on: October 22, 2022, 02:04:38 AM »
Please defined before, if Bitter Ends(BEs) opposing sides this never works properly;
unless only reverse pull on the active, locking, hitch side.
Bight is neutral/passive part, same mechanics either direction.
.
But don't want to end up with opposing BEs for Lapp.
May discuss different materials opposing BEs in Sheet Bend, but not for loadable Lapp(unless that is target).
Round Turn of 3x arc180 on locking side of any cures many of the ills tho.
If mixed ropes the locking hitch side should always be the thinner/stiffer rope.
"Nature, to be commanded, must be obeyed" -Sir Francis Bacon[/color]
East meets West: again and again, cos:sine is the value pair of yin/yang dimensions
>>of benchmark aspect and it's non(e), defining total sum of the whole.
We now return you to the safety of normal thinking peoples

Dan_Lehman

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Re: Reverse Sheet Bend
« Reply #4 on: October 23, 2022, 07:09:45 PM »
Please defined before, if Bitter Ends(BEs)
opposing sides this never works properly;
unless only reverse pull on the active, locking, hitch side.
Bight is neutral/passive part, same mechanics either direction.
I've no bitts in sight, and my ends are otherwise content,
never "bitter".   ;)

If one goes with my recommended 2nd or more tail wrap&tucks,
the difference between same-side (recommended) & opposite-side
orientation of the joined lines matters less.  YMMV, try it in the
particular cordage with which you're dealing.  But PLEASE, don't
stop with the only-version-shown single tuck of the hitching
line's tail --make a 2nd wrap & tuck, at least!
(Same thoughts for the Myrtle & Bollard loops (looping
tail through nippin loop of S.Part, from front or back
side) :: take the worry out of Which_Orientation by
making TWO wraps --that improves them all.)

My sense of the Lapp bend is that it found favor
when tying to FLAT material (leather straps, i.p.) ?!
That the U-fold part was happier to turn around
the tucked tail than to distortingly bend over a loaded
S.Part.  !?  (Sometimes, tying this in webbing/tape
in which I've a whipped tail, I put the tail --whipped
into a sort of short rigidity-- smack in the U-fold
apex (so, yes, VERY short end!).)

--dl*
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KC

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Re: Reverse Sheet Bend
« Reply #5 on: October 26, 2022, 12:22:22 AM »
i think of upgrade to RT of 3x arc180s as a 'pro' upgrade to most working knot functions of 1x arc180 architecture;
to me as perhaps a pattern shown here. RT replacing single arc180s on both sides of input pulls/SParts brings choke of Girth to magic of Prusik etc.*  Second arc180 does about get it, surely now both sides of host get pressed firmly into, but from there to 3rd arc180 even better geometry and frictions to me.  After that just more arc180s extends that same geometry but of greater frictions and area rather than upgrading to another 'tier' i think as did by adding arc180 #2 and then #3.   Also, odd numbers of arc180 like 3x arc180 deliver neatly to where (odd)1x arc180 would, headed back to SPart as most powerful and rigid forces** of knot node.  So generally upgrade from 1x arc180 to 3x as ends up in same position with greater external force expressions in RT geometry and compounding capstan reduction of internal tension force from 3x arc180 as well.
.
Node being an interruption in a smooth force line, whether being Hitch as termination or Bend as continuation or even errant Overhand locked into rope.  Rope was carried onto the great ships, but once in loaded use were called a line.  To me that means a rope in work as a line of force, node then as an interruption in this otherwise clean, undisturbed, pristine line of force flow.
.
A single arc180 to HH etc. is VISUALLY is closed, complete wrap around, but forcewise only the single arc side gets the full treatment to me just as a pull force from 1 side tho, not a grip around.  The seam side does not give full arc180 properties.   arc180s are the real most evolved workhorse for this.  More than one controls to grip from both sides.
.
i totally think Lapp more favored in yes flat leather, as for horses,  where lends self better; and more fricative than webbing/flat rope have always thought.
Unless purposeful reverse strategy to use in round (instead of flat) flexibles class /round string as safety overload fuse/release etc. where want to exploit/play off of the inherent weakness as a win/not loss, even of opposing BEs.  For this would also leave loose-ish to further favor clean release/break-away from belt loop or hat keeper, necklace etc.
.
i think previous tucks can help, but the real player is list of arc180 leveraged friction reductions of internal tensions thru to BE, before the final tuck.  This is like only the rear most fibers in tree hinge really carrying work, from most leveraged position; the rest are little helpers to the main that is most critical.  The arc180 reduces internal tensions of the want-to-pull-out force, as also gives greater trapping force expressed external rope force as arc also nips that lessened escape force powered by internal rope force.  Similarly, in Timber Hitch, preceding tucks help, but final nip of most reduced is most key.  Especially if that was in the 11-1 region on clock, from a 6 o'clock SPart/input pull, as sweet spot radially for nipping.

 
 
 
 
 
* Look at same as Prusik of 2 SParts to eyes, only as a loop Prusik the SPart legs are self equalizing/balanced to always contribute evenly sharing work, not pull all or mainly just from 1 SPart/leg if pulled to side.


**
In model, most powerful EXTERNAL rope force is generally the primary arc after SPart function, also as a higher friction reducer, but notably before any other high friction reducers of it's kind.  This external rope force is expressed greatest in most evolved arc180 element that has a potential of 2x the internal force/tension at that point.  Both theories find mostly together then with greatest arc180 as primary arc fed right off the arc0 SPart(s) as fuel line feeding tension into the actual knot microcosm machinery.  SPart has the most raw and thus rigid forces in it's section of a knot or in full knot. 
.
Son is engineer and he lends that a key concept is engineers think of force as more of a ghost than physical presence moving thru rope, wire, column etc.  i have found it close enough to think of force as liquid flowing force per childhood lessons of thinking about electric force as water force to get a feel for electrical force.  Also found much of Oriental thought have run into speaks of flow of force in work, play, exercise, thought, mind, spirit etc. so that has always been my imagery/approach.
"Nature, to be commanded, must be obeyed" -Sir Francis Bacon[/color]
East meets West: again and again, cos:sine is the value pair of yin/yang dimensions
>>of benchmark aspect and it's non(e), defining total sum of the whole.
We now return you to the safety of normal thinking peoples

jarnos

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Re: Reverse Sheet Bend
« Reply #6 on: October 30, 2022, 02:02:39 PM »
...

Images would help to understand what you mean.  I think whether you need to add complexity  depends on your use case.
Jarno Suni

 

anything