Mounting A Portawrap - Hitch?

lxskllr

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I was just contemplating my new deadeye, and thinking of ways to mount it. Typically, I'd use a timber hitch. Do you all see a problem with making a roundturn around the eye, tucking it under the rope going around the tree, then doing a 3-4 link daisy chain? Seems like it would be quicker, and less fiddly than a timber hitch. Knife=portawrap...

IMG_20230324_191403761_HDR.jpg
 
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  • #3
I think I wasn't clear. I kinda wanted an opinion on the displayed hitch. The pic kinda sucks, but it's what I have. It's dark, raining, and almost everything I own's at work. I'll try text...

Start with the porty in front, sling to the right, wrap around the tree anticlockwise.

Do a round turn around the porty anticlockwise starting from the bottom, then tuck a bight under the tree wrap to the right.

Daisychain it by bringing the free end up, and tucking a bight through the loop you made. Do it four times. I think three would be enough, but the fourth's 'just cause'. Make the last link extra big to prevent it from being pulled out; maybe a 3' loop.

Why?
This would eliminate cycling every inch of a 15' tail around the wrap line in a timber hitch, and disassembly's even easier. Pull the free end of the sling, and the whole thing comes apart.

See any issues with this? The only one I see is the 'locking assembly' is close to the action next to the porty. I think it would stay out of the way, but I'd have to see it put together to really know.
 
I think I wasn't clear. I kinda wanted an opinion on the displayed hitch. The pic kinda sucks, but it's what I have. It's dark, raining, and almost everything I own's at work. I'll try text...

Start with the porty in front, sling to the right, wrap around the tree anticlockwise.

Do a round turn around the porty anticlockwise starting from the bottom, then tuck a bight under the tree wrap to the right.

Daisychain it by bringing the free end up, and tucking a bight through the loop you made. Do it four times. I think three would be enough, but the fourth's 'just cause'. Make the last link extra big to prevent it from being pulled out; maybe a 3' loop.

Why?
This would eliminate cycling every inch of a 15' tail around the wrap line in a timber hitch, and disassembly's even easier. Pull the free end of the sling, and the whole thing comes apart.

See any issues with this? The only one I see is the 'locking assembly' is close to the action next to the porty. I think it would stay out of the way, but I'd have to see it put together to really know.
educated climber has a bunch of videos about the daisy chain knot. i think they did break tests and had similar results to a running bowline..
 
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  • #5
That's a consideration. *The girth hitch on the porty takes ~50% of the strength away from the sling, and it's #1 in the line of fire. The wraps around objects before you get to the daisychain take much of the force.

*I think. I'm extrapolating from crane slings, which I think isn't exactly correct, but it definitely takes strength away from the sling. It'll break @ < the breaking strength of the rope.
 
in pull tests the timberhitch was slightly stronger, hse report paper.
port-a- wraps tend to stay where they are for sometime unlike branches so setup speed is not too important for me..still i have a pocket sling on mine.
 
I find it bulkier than it needs, so close to the working area of the porty. The amount of potential internal slack and the following slide when first put under load is a concern too. More movement = more friction = more wear and heat. I'd like to reduce that if possible.
 
I agree completly for the slack in the rigging line. I'm speaking about the slack in the knot itself on the porty's sling, even well dressed, before it tightens when comes the first (serious) load.
 
Sunday p/reachin'>>
IF, one sweats the line proper prior to adding wraps, does not mount the porty too high, or adds MA with a rope grab or such; slack is less of an issue.
This is true (sweat/swig), also less play to impact with into system(so also making easier untie); more carefully laid and aligned parts just as with rigid supports.
But at/against the Standing Part(SPart) wrenching(meaning pulling/shearing across rope column at Samson angle/across)a tightened grip trades off for strength/efficiency loss tho is another consideration to watch/not overdue.
On removals would cut small Humboldts to bed rope into
While on preservations of host/Porty anchor would look for any imperfections that could to bed rope into against projected direction of pull (up) to just tip the scales a bit more to my favor. Looking to give perhaps bedding lock against upward pull on opposite face of host than pull, 180 around from Porty other spots can help but all things being equal i believe that is the sweet spot.
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In any support against load i look for a proper support geometry made from material used, of course no sharp bends, only solidest parts exposed to brunt of raw loading/not any seam or other weakness and multiple support legs where can. Because would be true for sound support architecture in any suitable material, we are just using rope as the material here for the build. But same rules apply as always and all ways do. So i prefer a long eye of 2 solid legs exposed in hit and buffered thru turns before any sharp bends or seam/other weakness that are buffered back from hit and (at least) 3x180 degree arcs on the host tree arrangement...
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ABoK as a study guide shows 1arc/Single Turn on host anchor for standard pull at right angle ONLY .
Reference 2 fave chapters and the order of their builds (courtesy of wayback machine archive.org) as standards to this work :
ABoK CHAPTER 21: HITCHES TO SPAR AND RAIL (Right-Angle Pull) page/289" (standard simpler 1D pulls) vs.
ABoK CHAPTER 22: HITCHES TO MASTS, RIGGING, AND CABLE (Lengthwise Pull) page/297 (more complex now lengthwise 2D pull of across host + along host).
Chapter_21 starts with Half Hitch, quickly evolves into Timber; but only for right angle pull against the host anchor.
Chapter_22 starts with ruling out Timber for lengthwise pull unless pre-fix with Half Hitch to make Killick of 540 degrees of arcs (180+180+90+90 in lengthwise pull).
In dragging whole pieces with either Timber pulls across and can cause dragged piece to hop around sometimes like wildcat, but purr along nicely with Killick, for the forces are aligned right to now pull most properly along, not across the load., so there is no fight cross ways, just inline pull. This can be a very visible, dramatic and convincing change for what try to show here.
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My imagery/internal naming/digestion of ABoK lessons on this is that of a system support logic of geometries that always has to pull across host at right angle as an initial force dimension of pull. Then must add another secondary dimension of force pull if needs to then extrude support against a lengthwise pull in addition to gripping across spar etc. A single arc180 has a 1D pull, 2x arc180 adds 1D grip but seems takes 3+ to add/then extend a 2D support framework when loaded against with 2D force requirement of load to spar for Mr. Ashley's "lengthwise pull". The geometry model is my understanding/guiding model to his intent of consistent patterns shown. i count the closing of a Half Hitch as a linear(Standing Part) and right angle part(not arc180), and so only 1x arc180(radian pi) on the opposing side in Half Hitch build. This carries into Timber, that can find total of 180 +90+90 of pre-fix with (continuance thru type of) Half Hitch +180 for Timber for lengthwise pull; to look for total 540minimum seems pattern sifted to in all. Personal breakdown of loaded rope is forces can be defined to only 3 base elements :arc0(linear), arc90,arc180; so i look for these points in all, initially defining proper arc180 as most evolved t exclude, etc. to view.
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i have 'gotten by' w/Timber Hitch many times(seen some slip a bit too) ;
>>would insist on start with fig8 style(ABoK Lesson#1669 in right angle chapter_21),
>>then insist at least standard 3 tucks anyway(fig8 type Ashley lends is so much better found only needs 2 tucks) first few also kinda as spacers to me towards end nip in sweetspot region on opposite face of host than the load pull (again)that is so intense as to make the pre-fixing tucks as more nominal spacers to the big pinch/nip per Lesson#1663 positioning shown as savior (rated solid anchor) to Half Hitch treachery (just previously at very start of chapter rated skull/crossbones) if premium/king of the hill nip position alignment can simply be held on equal/opposite face of host than originating input pull DIRECTION(a most important key aspect) of SPart on the host. And i must always remember might be looking at highly textured dry bark and some one following advice on a slick, tapered.. In pre-ramble of chapter_22 Mr. Ashley lends that there are limits to this and even of adding dry ash, rubber matt etc. for grip to masts for what doles show for lengthwise pull...
BUT still would not for use Timber for the lengthwise pull anymore if can help it nor recommend again because of what i understand now of how that would be compromised in any material per these geometries. Just as with other materials can build several ways to same target once know rules as can with wood, metal, plastic etc. , but i think these are the most key, pivotal points to show here that would find as signature of most proper builds, to then draw yours into.
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This can be found to be too purist, but with stakes on high impacts, receding tapers and historical warnings i find cheap insurance with this prescription tho, and if there was an actual insurance, would probably be demanded qualifier as a proper engineering usage of the material just as with any other material. But, also gift to practicing purist is can't always see next set of peaks and valleys until can crest present point and know it well enough to sift to the rest. Sticking to this journey can pay off many and many times over later in more depth to layers built on, triggering more light bulbs and automatic forehead palm slaps in their wake.
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Sorry, seems am jest so knot feverish, and did give ya's a free dis-count/shaved at least 1/2 off this one...
 
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