When using half's/marl's before a cow or bolan, why not just use an O-ring at that junction instead?

eyehearttrees

Active Member
My understanding is that when you're using the tail end of your bull line to do 2 wraps around the log, the first / lower (half or marl)is the 'secondary' knot and that the higher-up (when tied) cow hitch or bolan is the 'primary' knot but that breakage occurs at the half hitch not the actual knot - wouldn't it make sense, then, to simply pass an O-ring over the rope before making the knots, so that when making the first pass around the log you put the tip of the rope through the O-ring that'd been slipped-onto the line, instead of having the line wrapping around itself?

Seems so obvious but I've never noticed it done...but my understanding is that breakage occurs on the line at that rope-union, that its weakness isn't only that it's the first hard-twist in line with the force-vector of line-tension from the anchor but, perhaps as significantly so, because of the rope-on-rope friction, I've seen break-test-bed videos where the rope 'cinches'/girths at that union by many many inches even on something that was ostensibly taut when set, stands to reason that having an O-ring slid onto the line, and then passing the rope's tail through the o-ring to make that 'first union' before heading up for the cow hitch, would greatly increase this 'weakest link' of a system (this spot is supposed to be the weak-link in systems where you're attaching the bull-rope directly right? Still uncertain where proper breakage would be if you're using a spliced-end to the line, and redundantly-strong nylon straps around the log clipped-in to a strong splice w/ a thimble in its eye...)

Thanks for any insight! Have all these o-rings and suddenly thinking I could put them to use this way lol actually it'd probably be better to use 2 rings than one just for bend-radius especially on >1/2" no? Got to say I'm still surprised that using nylon loops, clipped to spliced-with-thimble bull ropes, isn't *by far* the norm given how much stronger it makes it, maybe it's just assumed your rope is strong-enough even with the knots and you simply keep clipping-back the end of the rope as it gets worn? I setup my my new ropes with a spliced end with small plastic eye (just to help spread the carabiner's load), was only type that'd fit through my Safebloc or even the XL ring it barely fit through, have 5/8 and 3/4" generic steel rope thimbles spliced into polydyne as my extra/redirect/satellite/etc anchors, figure it's better to over-do it than under-do it with anchoring when movement in the canopy is easy enough -- but I've also got chafe sleeves on, I don't know even though I've got enough nylon straps' kN to over-do my line, I still feel like with the heaviest loads I'd want to be directly hitching but I can't explain why it 'feels' safer that way..
 

JeffGu

Well-Known Member
Because the half-hitch is a hardware free solution and shares the load with the running bowline. If the rope breaks anywhere it's because you dumped too much shock load energy into it. A metal ring isn't going to change anything.

If you don't mind a hardware solution, then why not use a spliced rope and a knotless rigging system? You can size slings that have a lower MBS than the rope, and you know where it is going to break and the rope remains undamaged... it isn't getting shorter and shorter from improperly sizing the load to the rigging system.
 

colb

Well-Known Member
The friction in the half hitch helps keep the running bowling from loosening when a negative block is yet to be caught. Also, seems like you would spend some time chasing down that ring... Cool idea to play around with. I'll be interested to know if you find it works well.
 

dmonn

Active Member
What you are describing is basically a technique I use to break small cord (and even some hefty monofilament) bare handed. Make a bight in the cord, hold it in your palm, run the bitter end through the bight and double back. Pull out the slack then give it a sharp jerk and the cord "cuts itslf" instead of your hand. Fun trick at a bar once you learn to do it one handed. The drunks usually wind up cutting their hand a bit.
 

eyehearttrees

Active Member
Because the half-hitch is a hardware free solution and shares the load with the running bowline. If the rope breaks anywhere it's because you dumped too much shock load energy into it. A metal ring isn't going to change anything.
I mean a single o-ring isn't much hardware and IF a standard half-hitch + bowline configuration is inherently one wherein failure occurs at that tightly-rounded, high-friction rope-on-rope contact at the half....then how on earth could you conclude "a metal ring isn't going to change anything"? The sharp angling, the rope-on-rope friction at that half hitch is surely a large% of why it's the fail point, no? If correct then, of course, putting an o-ring there to replace the rope-on-rope half-hitch(hope I'm clear I can take a pic if needed!), or better yet throw a Fiori's Ring on there to replace that half-hitch, you have most-definitely upped the ABS of that setup compared to a rope-on-rope half hitch in that spot (feel you may've misunderstood me..) And whether anyone breaks it or not is irrelevant here what matters if the ABS of that 10' tail of bull-rope on the log has gone-up.




If you don't mind a hardware solution, then why not use a spliced rope and a knotless rigging system? You can size slings that have a lower MBS than the rope, and you know where it is going to break and the rope remains undamaged... it isn't getting shorter and shorter from improperly sizing the load to the rigging system.
Cuz of that stupid 5', 3-ringed x-sling, so beautiful & convenient and it was my main anchor for a while, now I've got my Safebloc on something more convenient (tec whoopie) so I will be going knotless soon actually taking the hardware out of that beautiful, stupid 5' sling (stupid because it has Lrg rings when it should just have a pair of XL's) and using its XL ring alongside a #3 Elevation Canada ring on a new 7/8 TEC 5' (no, 5.5 or 6') with one on each end is my last step as I've already got or made:
- nearly 10 loops (mostly from Mercury which is 8.5k lbs and 3.5% elast., w/ chafe sleeves on most some w/o so they could be used as hitches if ever needing stronger hitches),
- some 5/8 tec "eye&eye" slings (using generic 5/8 thimble in one of the eyes, dunno why but like having one end each way sometimes one is beneficial for instance I could send things down a line or double-whip using the thimble, or when used as regular choker I've got thimble-on-rope instead of rope-on-rope at the choke which IIRC is a fail-point for a simple choke/cinch)

Yeah if I just order 12' of TEC and a #3 ring ($45) and take that XL ring I'll have my 'super convenient anchor' (thing still gets more use than my whoopie which I thought/hoped would get the most) and all I need for knotless, hadn't really clicked that I've got eveything now (well need a lil more good steel hardware, won't use alum in rigging-connectors if anything I'll just get more steel ISC generic ovals they're good and should bite anything, already have large d-shackles and delta links if needing to bind larger stuff and still get a spliced eye (or 'biner) in the mix :D
 

Daniel

Well-Known Member
It's true that the half hitch or moral becomes the weak point .

This was not commonly known when I was getting into the business. we were told that the half hitch"" shares of the load however it is not sharing much of the load if you're putting in a weak point in the system.

In my opinion it would be good to change strategies when bringing heavy pieces and bypass the marl or half hitch

just how that's to be done is questionable but you certainly could notch the back side of the tree to hold the rope if necessary.

I'm thinking in extreme cases it wouldn't be bad to take two wraps and then put your bowline on. that would put a lot less force on the terminal knot

I mostly used a 1/2 hitch just because it makes tying the piece easier. the hh acts like a stopper knot to keep the hanging line from pulling down as you tie off and perhaps makes untying a little easier.

or maybe it's just force of habit
 

SomethingWitty

Arkansawyer
Man, what I am reading is definitely a little more trouble than a marl but it could still keep your bowline tight enough to not move during free fall, still adds friction before the bowline to increase the load required to fail there, and eliminates a weak point.
It might add the 10-15% breaking strength to comfortably rig things you would otherwise be double whipping (which is a bigol pain to set and run).
A large cross section ring might be needed to see the full benefit, but that is an easy thing to leave on the truck until you need it.


I need an enforcer to do some tests.
 

*useless info*

Well-Known Member
Rope, as a flexible, can only properly support against linear force on it's inline axis, not cross axis as rigids can do also.
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A simple hitching inline thru rope meets the host mount at right angle. 1dimensional pull against 1dimensional rope support as in ABoK right angle hitch chapter. Ashley leads off his very next chapter on LENGTHWISE pulls showing Half Hitch preceding forms thru the chapter exclusively with few exceptions of tresse type geometry forms. And adds not to expect the same service and reliability of right angle hitch forms. Even when used on spars might leave varnish tacky and hitch or apply wood ashes but really preferred slit innertube over wrap on spar for grip.
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I think Half Hitch /Marl preceding forms increase 180 degree arcs from simple 1 arc to 3 arcs, taking the support part of rope to 2 dimension against the now not inline/ so 2dimensional pull.
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The force trace on load is firmer down side than in turn around spar as the linear force path continues from Standing Part input force into hitching. The turn is looser like in Bowline proper , because spar forces turn out of the linear path of force flow. Conversely if do same to Half Hitch of Sheep Shank or Sheet Bend the turn/loop lays flat into the linear force path and then turn/loop is tighter as our mute witness to what is going on. Linear Force Trace.
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Half Hitch pass thru (as opposed to Half Hitch terminating/end of force flow) or Marl are actually sharper deformities in rope / so less efficient architecture / so fail earlier than knot parts they precede at this lengthwise angle of pull(but more neutral at right angle pull).
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Some of other factors of slip/steam release help, but as always and all ways I think the geometry and impacts are most definitive. The Half Hitch / Marl preceding forms give proper linear path down side AND 2dim support against 2dim load. Also the double grab as almost/ right on and 2nd check, all working in concert.
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Similarly, would say round sling for lengthwise pull, not eye2eye, unless eye2eye laced in Half Hitch preceding form. Round Sling does give shared effect and 3arcs too. Half preceding not so much as noted, but then counter intuitively spreading out wear by larger grip pattern. If drag log behind truck with just Running Bowline can flip around like angry wildcat if off center CoG of real force especially if not long length. Flip Half preceding on nose and aligns to clean, purring pull.
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LINEAR FORCE thru 2dimensions.
(Disclaimer: you asked!)
 
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*useless info*

Well-Known Member
This is a fave topic, many drawings, especially for the linear force flow concept/load bearing of simplest/single dimension of competing Equal/Opposite pulls. Visualizing a single point having no force only w/o direction potential. Force trying to persist in a direction, makes 1dimension linear force line in simplest forms. Training eye to see correctly, allows it to give most correct info to brain. To solve present problem and more truly see the connecting tangible fabric to same principles in all around, every day. Dealing with these common principles so rawly and magnified has been real gift of tree work, transcending to most basic lessons of ancient's wood and rope work as base mechanix of human understandings funneling outwards to many things.
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In chapter_21 ABoK starts with Half Hitch(HH) common and 2 versions of higher Nip positions of HH (termination forms of HH in my terms).
>>As next rolls into Timber Hitch as like extended HH, covering all 3 previously shown Nip positions in separate HH's as used all at once in Timber.
Then goes into the rest of the Right Angle Pull Hitches that the chapter is titled to and about.
Right Angle pull places the 1st arc/primary arc directly INLINE with the linear load pull, as simplest/cleanest support. And actually about all working hitch forms in book are of the simple inline force type of right angle host grabs to posts, hooks, spars etc.
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In chapter_22, immediately following, he introduces Lengthwise Pull Hitches as worst angle of pull to assert, as parallel to load/host mount. This breaks the peace and clean simplicity of the most proper single dimension pull of right angle host to me, as it is not INLINE thru rope from primary pull (Standing Part) and primary support (1st 180arc) therefore not in same dimension, is now 2 dimensional pull in my model, so needs 2dim support response to match i think. Here Ashley shows to precede with a HH pass-thru type and not to expect as good results at this angle of pull as a proper right angle pull. Preceding HH/Marls rule chapter_22 except for some tresse forms. 3arcs give 2 dimensional support pattern between the 3 arc peaks thru/into load, from the linear input of Standing Part ; while providing extension of linear path to this force input too. Friction Hitches are included as they are lengthwise pulls on a spar or rope too, host rope becoming more of a rail than rope in this model, so this is seen as a Hitching too. In this chapter he even has HHs preceding rope ending with just wine to mast as final anchor in mute testimony to force reductions, later in book even shows similar pull against a tack, when preceded by HH's, even on unfriendly/receding taper, while at this worst angle of pull!!
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Here are ABoK's (pass thru)HH's that evolve to Timber Hitch in my mind and also in order of presentation in his book, some variety and points he makes to knot properties in different types of HH's, then Timber Hitches, then a Killick where he shows at start of a most different lengthwise pull chapter where he says not to use just Timber but precede with HH form (that i call pass thru HH vs. the first 3 HH's in pic i call HH terminations).
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Note how the best HH/high Nip (if force maintained to maintain key position) is INLINE with the force input of the Standing Part as very demonstrative of the linear theory persisting in path thru/into, more than around..
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another view (link)
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My most often used primary examination of knot is a hook concept of the 1st non-arc/straight part (Standing Part) as force input and 1st arc (in Hitching or dual competing hooks in Bending) as knot internal receiver of input force from Standing Part, that attaches to host. Rest of 'knot carriage' is just to backup and stabilize the position of the primary support arc as it attaches to outside world load as force input thru Standing Part. i find this linking between worlds of outside knot and inside knot to be the tightest and thus most rigid part of rope, so thereby giving much definition to the forces of the rope. Here is 1 view of this phenomenon thru metal hooks:

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If rely on degrading force force tracing AROUND load/host mount CAN make it thru some, but not as raw a mechanix i think vs. asserting geometric of 3 force points/arcs that work in rigid or flexibles, then adding the hug around of rope as even more, but not to forsake the deeper, rawer more innate force model geometry shared/encompassing flexibles and rigids. The secrets are in the arc gripping into, more than arc gripping around types of loading i think as i trace these things AND pro-viding linear force path that linear force fights to maintain, even as degrading. If we don't watch both of the magicians hands(arc force around vs. arc force thru/into), and just track the more blatant, might miss the magic one!
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i think there are a number of concepts less seen found in these pics, that rule all of knotting
>>and some beyond flexibles into rigids , as view of common over-riding principles containing both flexibles and rigids. i can explain many knot things by starting with hook model concept, after years of just ending up there!
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Linear force and angles in any are the same in any medium of loading transfer.
As i seek a rope principle, i try to find the rigid counterpart for different facet of same gem trying to understand, revealing either over riding principle(s) shared or defining difference(s) to go forward with.
Originally Posted by Ancient History Encyclopedia: Greek Mathematics:
"The technique of abstraction, based on ignoring physical considerations which are seen as merely incidental. Whether it was a rope, a piece of wood or any other physical object was irrelevant. It was all about properties of 'straight lines' connecting at angles, nothing more.
These lines are simply mental constructs and the only entity necessary to the solution of the problem.

The process of abstraction is about getting rid of all the nonessential elements and considering only what is fundamental."
Euclid's "Elements" manual is said to be the 2nd most published millenniums old text in eternity, for these are the other things that rule our world, and perhaps in more Earthly matters.
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1x180 arc on host mount give a redirect with friction.
2x180 arcs on host mount give some real grip into host mount all around.
3x180 arcs on host mount give more 2 dimensional triangle grip into/thru host mount
From linear input of Standing Part(s) (plural in Bending)
 
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Jehinten

Well-Known Member
I'll admit I do not often use a marl because it does weaken the rope, instead I choose a running bowline at a crotch if possible and only use the marl when the piece is heavy, no crotch, and smooth bark.

If you want a piece of hardware in there, why not use a backbone instead of a ring? It is designed for such use as a terminating knot and the marl can be tied midline. Run the rope through the center and tie your bowline. Pull a bight around the piece, through the center and hook over a side cleat (or whatever they call those side nubs on the backbone) downside is the weight of the hardware, maybe the mini is a better choice?

Certainly worth mentioning, I've never used or held a backbone, just brainstorming if anyone were to want hardware in the system.
 

SomethingWitty

Arkansawyer
I'll admit I do not often use a marl because it does weaken the rope, instead I choose a running bowline at a crotch if possible and only use the marl when the piece is heavy, no crotch, and smooth bark.

If you want a piece of hardware in there, why not use a backbone instead of a ring? It is designed for such use as a terminating knot and the marl can be tied midline. Run the rope through the center and tie your bowline. Pull a bight around the piece, through the center and hook over a side cleat (or whatever they call those side nubs on the backbone) downside is the weight of the hardware, maybe the mini is a better choice?

Certainly worth mentioning, I've never used or held a backbone, just brainstorming if anyone were to want hardware in the system.
We have a big one.

It's motherfucking big and heavy. Like a medium size POW. It was a gift at a competition from someone who knew that they wouldn't use it.
 

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