Rope

[DMc]

.
The Porty is a funny tool for defining how a round turn works because it tilts off axis and, therefore, changes the whole dynamic. A strap-on bollard might be a better choice.


I understand your thoughts on the counter force of opposing half circles but that is not how I think of it working. In my mind, a round turn, in pure form, has the load entering and leaving in line with each other and perpendicular to the cylinder. The resulting load causes a continuous and uninterrupted constricting force working to pinch off the cylinder similar to how a garrote works. In use, as with a bollard, this creates a friction that we use to our advantage.

 

[theTreeSpyder]

i think of a solo half circle arc as a frictional slip to other side.
But multi /more than 1 half circle totally different mechanic that invokes more of a constriction/clamping drastically increasing frictions and inducing grip also .
.
i think trying to really see/describe/manage any physical distance or force, MUST look at cosine (column forces) and sine (non-column forces).
The column is just a desired straight path between the equal and opposite forces in the scenario, thru connective pathway device of tool chain given.
>>then the volume of forces is divided to that cos(cause column line between equal/opposites) or sin(not of the column cos/cause)
.
These are so pervasive all around you, as to be unseen/undigested/bland but your 'animal eye' that instinctively registers,compares etc. to keep you safe, by cross comparing things etc. can tell when things aren't right, like in a drawing etc.
A big game changer in the computing world was proper shadowing.
Old cartoons etc.just have a uniform dark image behind the principal as it's shadow.
Later years they tried to give a more natural,fading shadow 'gradient' of dark shadow to lighter and lighter for external drop shadows
>>and internal beveling/rounding shadows of gradual change.
But your animal eye could tell it was fake/mechanical feeling in the static changes of just lighter and lighter bands around principal look/feel fakey to your eye that has been watching everything all your life.
NOW most properly, the gradient shadow changes are to a declining cosine etc. type scale.
>>NOW game shadows etc. look Natural; in drawing circles it is called 'more organic' it is so real and Natural!
Your animal eye can tell because it has been comparing these things from birth, and can tell the fakes!
That is just one example of how pervasive cos/sin are in everything we do,see, touch etc.
.
In multi-leg rope supports 120degrees spread of 60degree deflection each leg is a dividing line.
More teepee/more closed pointed lends to extruding support column forces from the rope.
But flatter than 120degrees spread extrudes wrench tightening forces from line more than support column.
So to get the right service from the rope, should deploy by this math; so it can stand fer ya, not against your target efforts!!
.
i hope this shows how easy it is to peek into how this works and changes with calculator as tangible evidence.
Even if not punching calculator keys, perhaps just view over the rate of changes, and how they can ruin your day, where redline is etc.
In the end i also show how same numbers and lessons relate to lean leverage, not to confuse;but rather show the value of learning these ancient 'secrets'.
.

.
A TON of change in a quarter second, from 1 degree of change is VERY HIGH IMPACTING; and can make or break everything and everyone!
.
In actual usage, application: trunk wraps for support of pulley redirect; should try to extrude/conjure forth the SUPPORT NOT WRENCH forces of line:
.

.





Clean and simple: Nice 'teepee' point on angle much less than 120 spread/60 deflected each support leg
>>gives 4 support column legs to carabiner
>>maintain 1 wrap as Round Turn on bomb proof anchor for grip/not used as support column to carabiner (specializing each wrap to purpose)
>>hide 'seam'/knot on that wrap to buffer Achille's Heel from primary loadings and hits:
(knot in front face of this wrap leaves knot weak link in very inspectable position)

.

 

[theTreeSpyder]

Contradictions in basics: Stopper Knot theory.
.
<iframe width="550" height="400" src="//www.youtube.com/embed/jKvTKHzqy8M" frameborder="0" allowfullscreen></iframe>
.
i again blame knudeKnoggin for the basis of this view of how OverHand can give more stopper than fig.8,and Ashley's Stopper even more, also of course.

 

[theTreeSpyder]

Always been working maybe towards something like this;
with l-earning Flash on side etc. Then that all fell thru on the web side.
ver.1 of one of/if not several fave topics, as i come up for air and light out of my creative cave..
.
<iframe width="854" height="480" src="//www.youtube.com/embed/ZwxGuIK_VgU" frameborder="0" allowfullscreen></iframe>

 

[theTreeSpyder]

This is actually part of bigger project.
'Even Woody' should be fluent with cheap throwbag strategy. >> some guys can even throw overhand like baseball 60' up accurately (not me tho!)
i have even used red car utility towel as bag and filled with dirt to paracord etc. in a pinch many times.
Favor something like bag of dirt, ball bearings etc.that absorbs shock, deforms and just slides down into target.
NOT hard object that can bounce away from target, and dent your coconut as well w/o brain bucket!!
.
<iframe width="854" height="480" src="//www.youtube.com/embed/fMx5ucqQX8E" frameborder="0" allowfullscreen></iframe>
.
MBH link makes me remembers; Was doing Flash animates when we started in this non-space here, WOW so many years ago!
Just not Youtube video conversions etc., seems they were more or less just breaking ground too!.
WOW Butch! Look what ya done, thru many naysayers bro!

 

[Marc-Antoine]

Just to say, the Ashley's stopper knot looked too complicated to me at first. Studying closely, I found that it's actually a bowline with the working loop downsized to zero. Now I can try it without headhache.

 

[theTreeSpyder]

Slowly but Shirley.
.
<iframe width="854" height="480" src="//www.youtube.com/embed/Ma5lpEJ6BvU" frameborder="0" allowfullscreen></iframe>
.

 

[theTreeSpyder]

i always try to show a more fluid/abstract imagery of power as a flow of force.
Compress so much power as a psi, into half as big a container(distance) have 2x power etc. covering less distance
>>slower output movement than input movement in same time slice.
Play it backwards, input to opposite end and take output from where input was: lose power and gain speed.
>>assUme 100% efficiency total input of force x distance will equal total output force x distance.
>>this gives several attacks to figure out problem, and a checksum (verification) as well (should match).
.

For decades nothing has illustrated this to me more than a differential windlass(evolved to chain hoist) invented in the Ancient Orient.
So much power change in so little space by playing the fiddle on the numbers and Nature dances along so consistently on base pivotal concept that can see it around this counter-intuitive turn!
This concept then carries into gear boxes, to make so much change in so little space.
Actually all power leverage changers are differentials between input/output; Chinese just compounded the effect, giving more illustration to the laws. The difference in total distance input/output is the leverage increase multiplier of effort, so much so, law continues even here.
.
Not much to do with tree work;
except a front row seat of pivotal principles deal with daily(just different facet view of same gem), in rope.
and how the mind of man can capitalize on them!
Confined by the rules, but then so empowered by them too, if can play the chess game right when door opens to it!
.
Old Ship Windlass/Capstan winch pretty cool man power

But, the Ancient Chinese Windlass certainly is it's own marvel.
.

.
Power ratio from smaller to larger drum will be same for any pair 1/4" difference!
>>Larger size crank input for more power, or changing handle to hole on crank for less power (faster speed to reposition, or lighter load etc.).

 

[Tree09]

Differential hoists are awesome, excellent as always Kenny

 

[theTreeSpyder]

Thanx, things get much larger for real power w/o that differential trick!
.
This is supposed to be a rebuild from Ancient Rome:

.
Hamster cage cranes were all over later on, show thru history, i've often thought mite have helped with pyramids
>>but always just see ballast/lever crane lift arms, not rotations of wheel input.
Many builds like this simply didn't make it thru the portals of time:

.
Of course all power produced transmitted against load by rope after condensing distance into smaller container.
This is real radical stuff, shut down a town, kill anyone that talks during proceedings( had to keep airwaves clear, can't let anything get out of hand, have to notice everything)
>>Each leg of line input goes to several men, that are pulling leveraged devices that then delivered to each leg of line those men's pulls amplified and combine the whole for pulling force!

.
Even with all this, even in rotational input that can keep inertia going from all force input(no reset for another pull)
still 'flat'/linear/straight on problem solving compared to compounding, turns rules back on self of differential/Chinese Windlass!
.
i think this type of raw understanding of extreme loads and compounding against, especially with rope, compares to men at sea, trusting lives to rope, wood and sail, not sure if Earth was flat and forging on, army training manuals, rope rescue etc. are as close to a rope heritage i saw as in working trees.
.
Of course now have many mechanics to buffer between us and the raw work.
But just as Doc Shigo invited to 'Touch Trees' , can get out of touch by being buffered from raw tools to raw forces.

 

[theTreeSpyder]

i remember many things that stick like snapshots of pivotal benchmarks and mysteries.
Some haunt as undigested nagging puzzles to decades later sort that is why the butcher did this, or dear Grandma that..
or why this worked and that didn't. 2handing concept have tried to present is surely 1 long running example here.
.
This to me has always and all ways been wrong; or rather not so right even tho seemingly well drawn and from reputable source parroted out thru same.

.
This to me shows a Clove; that would most NATURALLY / undistortedly carry to the side as a Crossed Turn is 'cranked' to carry in front.
>>on a larger host mount, i'd think this distortion would be even more 'toxic'.
Carrying from most mount centerline of host can be better, but then would make BackHand Turn base like Turn +2 Halfs, Cow +2 etc.
(not Crossed Turn family of Clove, Bag etc.)
.
2Half Hitches after Turn is best because only Nip is in worst possible Nip location, so backup with another Half Hitch(HH).
>>i think of this as main hitch pin and lil'hairpin of cotter key keeper
.
2HH's after Clove is needed even tho expect full Nip before HH, in case jostled etc.; because Clove handling Nip no pressure in tail to keep first HH aligned as failsafe. But would think goes the long way home around to carry Clove at side, not cranked to front.
.
Anyway, in my whole geometric architecture of temporary structure should be trued as close as possible to perm type arch. imagery/illness;
this has always stuck, undigested and my shrink said i should get it off my little chest!
.
Crossed Turns to me are a complication added to Round Turn (compounded Turn) << Turn(compounded line) << basic line ( descendant << parent form)
>>all Naturally carry from side; anywhere else is further distortion ; strength/efficiency loss
>>and torquing a loaded element to constantly load more than needed /wear out static strength and dynamic elasticity per-maturely just like metal etc.
.
Turn + HH to me is BackHand Turn family (Cow, Timbers, Fig.8 etc.) that do Naturally carry from host centerline and would then give HH's to suit.

 

[theTreeSpyder]

Ashley's Book of Knots lesson#1781 quotations on using 2 Half Hitches for safety.

"Two half hitches will never slip"—Admiral Luce.

"Two half hitches saved a Queen's Ship"—Anonymous.

"Three half hitches are more than a King's Yacht wants"—Admiral Smyth.

 

[theTreeSpyder]

Knot base structure Crossed Turn is complication to Round Turn to induce extra friction before the opposing half circles.
Crossed Turn family has several related members with similar mechanix !

 

[theTreeSpyder]

 

[Marc-Antoine]

Thanks to explain this point.

A saying (translated) from my scuba diving days, to tie a boat : a round turn and two half hitches never let go
(more literally, a dead turn and two half keys never let go).

 

[theTreeSpyder]

Round Turn and 2 Halves are a base reference point; almost an Anchor Hitch + Half.
>>If line was very stiff/hard to work, especially older times; Round Turn and 2 Halves was called an Anchor Hitch and used so.
(Actually the said Bend to Rail and Anchor, sometimes ring, but most names changed to more normal only line extension is a Bend mostly now)
.
A Round Turn, is a totally different animal to me than a Turn. A Round Turn is a real workhorse, a Turn is a frictionalized slip in knot usage.



.
Better Half Hitch and Timber Hitch forms and usages:
.

The Timber Hitches list almost immediately in ABoK "CHAPTER 21: HITCHES TO SPAR AND RAIL (RIGHT-ANGLE PULL)", only preceded there by 3 Half Hitch base forms. The context begins with typical Half Hitch#1662 as worst security/nip warnings warning with Skull/Crossbones, but a base structure to build on. Then shows the most security at top nip/opposing the linear load pull position as a safer Half Hitch form#1663 awarding Anchor icon if constant pull. Then introduces Timber Hitch #1665 concept from extension of worst nip Half Hitch tail#1662 . #1666 then shows Fig.8 concept as upgrade to Half Hitch#1662 and shows the nip position pushed to half way between normal and top nip Half Hitch. Also adds a geometric consideration of:"particularly if the encompassed object is small." of even higher nip. #1668 then shows the Fig.8 Timber Hitch with nip more to side and not bottom as improvement.

Next trick is in #1669 Fig.8 Hitch with Round Turn. Where the Round Turn is around the Standing Part and Fig.8 portion actually pictured as fig.8 Timber Hitch and so adds that the "Round Tum on the Standing Part adds materially to the strength of the knot.">>i try to use this principle in may things, knudeNoggin adds that if Have a Round Turn on host before Round Turn on Standing Part, you don't get the strength increase. i say that is because of drop in rope tension can't feed force to the Standing Part to produce the affect.

Next chapter is "CHAPTER 22: HITCHES TO MASTS, RIGGING, AND CABLE (LENGTHWISE PULL) To withstand a lengthwise pull without slipping is about the most that can be asked of a hitch. Great care must be exercised in tying the following series of knots, and the impossible must not be expected" that starts off with a Timber Hitch preceded by 'lengthwise' Half Hitch form to convert Timber from "RIGHT-ANGLE PULL" to "LENGTHWISE PULL" usage in the back to back chapters.

 

[theTreeSpyder]

 

[theTreeSpyder]

 

[theTreeSpyder]

Many failures seen, or excessive loading wears placed by simply not grooming the geometry smooth.
My hard knocks lessons make me shudder some, as relate to the excess loading strains etc.
i wasn't all with the 'simple complexities' of geometry any more than most in high school i guess.
.
My most vivid work geometry lessons came from working out after school, working at father's hardware store and on farms in summer too.
Then later to geometry forces felt learning to drive, and watched for on tractor etc.
.

.
Iron Cross gives lots of strain at shoulder etc. but no support against right angle load as any other shituation.
Iron Cross support is pure lats, as those muscles are at better angle of support to load!
Should have some generous teepee in our rigs,but none in Iron Cross!
Looking at some load angles, brings me rite back to Iron Cross, can even say ouch in pain....
.
Iron Cross is held for the longest 3 seconds of your life to get credit;
but is only a 'B' move,
to get top 'C' points; had to hold in combination with legs perfectly straight in front in Lseat,for an even longer 3!
(But somehow l-earned to automate Iron Cross and focus on Lseat, at some point pitting their pains against each other, rather than cumulatively against me, at least that is what told self to help psyche thru as internal coach!)

 

[Tree09]

that's badass Kenny, keep up the good work!!

 

[MasterBlaster]

And here he is!

 

[theTreeSpyder]

Wish I had later pix, or even just more, like I wish for tree werk.
.
Learned to listen to and tune force thru bod to orchestrate different effects. SUPREME CONCENTRATION in own space, almost meditational yoga movements. Internally naming conducted forces in own nomenclature to organize, call out and command these things. Later extending same to outside self.
.
This guy is real deal tho, never even saw this level live:
<iframe width="854" height="480" src="//www.youtube.com/embed/H_QHuJyYI0g" frameborder="0" allowfullscreen></iframe>

Very typical chalked hands start to keep dry to slide. Lifted up extra high for rotation seating and drop straight down sharp to seat hands and pull surely straight. Straight bod, rigid, even toes pointed to get full points, hard to concentrate on all, but in end helps leverage swing movements. The draw to cross is Butterfly as opening move statement. Iron Cross with Planche(horizontal bod hold) is sever frontal bod strength. Can see trying to shorten arm levers, not hyper extend like for swing moves. They'd ding some points off at end some for that landing step in vid! Very tough task masters! i think you can almost see he knows step cost him,but must maintain confident, prideful stature to not worsen point faults.

 

[theTreeSpyder]

i did work to expand this body knowledge sense, and would often say aloud or just to self, well if the rope was pulling on me like that; at that balance point,it would feel like this, kill me like that etc....
.
Came time to roll huge meat logs, would look at side and see pivot on ground, like hands on highbar to 1 point in center, half the weight going forwards, half backwards so is balanced to not moving. Just psyche into breaking that still inertia and keep moving. Many times standing on side of log towards target and grabbing other side of log and pushing down with leg for bodyweight + 2x leg effort kick start... Of curse stay on side of log, and jump off at rite time and guys keep going, so not OSHA approved.. Anyway, gymnastics totally changed by approach to many things.
.
When trying to understand something i try with minimal variables such as parts. Also, find single switches between can and can't that make all the difference to distill out and trace into other things. Like experiment try to vary 1 element input and see what consistently varies on the output side of the pipe. Square Knot Family to study have been this for me. The simplest, frailest slips, that must be set right to function, lend views into that world.
.

.
What Knot is kinda a slick trick, can show as secure, flip the switch, hand to target kid/wife etc., and knot walks out when they try..

 

[theTreeSpyder]

Finally found lost link remembered for what i think is very key vision into brakeForce mechanics on bollard type simple pipes like Porty. But would then extend to cranking capstan, why to always keep at least 2 turns on drum of winch (so no raw force possible to termination) and even inside the secret life of knots..
.
Technical Paper: The Mechanics of Friction in Rope Rescue presented to International Technical Rescue Symposium 1999
by Stephen W. Attaway:GA.Tech Masters Structural Engineering + Computational Mechanics (modeling stresses, displacements) Ph.D.
.
i believe this fully explains what we 'feel' in working with Porty AND turns of Friction Hitch, any Round Turn + etc.
>>very powerful strategies, that math/geometry offers explanation for.
>>including, how simple, slick, small Porty is such a POWERFUL friction device etc...

 

[Marc-Antoine]

Very interesting read, thanks.