International Guild of Knot Tyers Forum

General => Practical Knots => Topic started by: Dan_Lehman on February 15, 2020, 08:50:46 PM

Title: *Knot* Characteristics (what is "knot"?)!!
Post by: Dan_Lehman on February 15, 2020, 08:50:46 PM
I've said previously that the understanding of knots
could advance a little were people to think of not
"knots" but "so-knotted rope" as the entity to which
attributes such as security, strength, ease of un/tying,
et cetera were attached.

Here is the OP of an arborist thread about "climbing
(aka 'friction') hitches" --about the particular materials
AND forces
to which favorable behavior is seen.

https://www.treebuzz.com/forum/threads/rope-wrench-hitch-rope-compendium.33714/ (https://www.treebuzz.com/forum/threads/rope-wrench-hitch-rope-compendium.33714/)

Quote
I searched for something like this endlessley when I first adopted the rope wrench system and added it to my VT for my first ever SRT experience. It was awful! Hitch binding on descent was the worst. It took me a lot of trial and error and searching different combinations of Rope diameter/hitch type/hitch cord to really dial it in.

I propose to anyone that reads this, if you have a system that works very well for you, type out what combination you use as well as your body weight. I will write out body weight categories and as you respond I'll fill them in, so that anyone searching for a combination that functions well can simply look at their body weight and see a combo that has been tried tested and true.



145lbs - (4 up 1 down Michoacan / 8mm beeline 23-24" long. / On NE fly)

(9.3 epicord, 4/1 micho, Samson velocity.)

(10mm armor pruss, 3/3 vt, tach)

155lbs - (Hh2, 6 wraps of hrc on sterling tendril)
(3 wrap 2.5 braid VT Tachyon, Imori, +1 wrap for Kernmaster.28" spliced 10mm Armor prus)


165lbs - ( 4/1 michoacan with 9.3 epicord on kernmaster)


175lbs -


185lbs - (Poison Ivy 11.7mm/ 5 over 3 VT / Oceans 8mm)

(New England KM III MAX 7/16" with 4/1 Distel and 9mm ArbPro 26" or 9mm Epicord 26")

(Yale 11.7mm AZTEC with 4/1 Distel and 10mm Ocean Polyester 28" or 10mm EpiCord 28")

(any Yale 11.7 or Cougar or Tachyon or Escalator (any rope really) 3/ 3 VT with 9.3 mm EpiCord.)


195lbs - (NE KM III Max 9.3 Epicord, hand spliced 31" VT 4/2.5 alternating with 4/1 Michoacan to extend life of hitch cord)

(Cougar Blue 28" sewn 9.3 Epi 3/4 VT)


205lbs -


220lbs - (Arbormaster( Bigfoot) 10mm AP tied at 24.5" 3x3 VT bottom cross on the tether side of the RW)

265lbs - (Htp addiction 11mm/ 4 over 3/ 9mm arbpro)

335lbs- (5over 1 Michocan with 8mm 30" armour prus or a 6 over 1mm armour prus 32")

So, there's a variety of rope-on-rope combinations,
and hitches used,
for variously weighted climbers.

--dl*
====
Title: Re: *Knot* Characteristics (what is "knot"?)!!
Post by: KC on February 17, 2020, 12:02:09 PM
Very Good!
.
In basics i think we skip over many times rope construction;
as to how/where the forces are carried thru the rope pipeline.
>> Mostly in 'kern', 'mantle', shared or is there even a kern?
.
In Arbo ropes, old classics; have 12 and 12 strands, newers have 24 and such, 1/2" round.
The less round/nubbier hand and friction hitch grip is hollow/core-less
>>while 'rounder' 16 sided /strand is smoother and has core for stretch and stability, maintain round, more than strength
The hollow 12 maintains round very nicely caring over 1 ton with wraps/turns around a spar, this is tough rope
easier to grip for pull line, but not as smooth a ride for friction hitches. due to same nubbiness.
Could start off learning on 12 that becomes easier to grip lowering line as advance to smother 16, later 24 etc.as rounder, smoother host.  I even favored Tenex 3/8 friction hitch cord  that flattens for some climbing
.
So many factors in these things on even a normal day /usage.
BUT, friction hitches require the hold, untie-ability etc. of knots, but also adjustable position and hold
>>so friction hitches as a class i think require more scrutiny
>>but especially when getting to slide LOADED and hold, even more so 'tuning' knot/materials/personal styles and yes weight
In trying to hit this nether range between can and can't slide to suit on the fly, each has their own way, tuned to them
This is easier if one end of line terminates on saddle, rope serves up over support and back to climber for friction hitch this leg to saddle
>>so now has 2/1 - friction over own self, and reduced load on friction hitch
>>but then pull down on friction hitch, forcing it to move (this is part of tuning to make sure it is not clamped shut too hard)
AND friction hitch unloads mostly like this leg was failing and load switches over to the more static leg terminating at saddle
>>overhead friction that was loss against 2/1, is now helpful buffer
>>climber can rapell, and let go of hitch and locks(if tuned right)
>>at end of day, support system is retrieve-able!
>>system is called DdRT Doubled Rope Technique (as opposed to DRT Double Rope Technique of 2 separate lines)
Really trickier when they are on a SRT Single Rope Technique system
>>Smaller range of knots and styles for each to chase holy grail of slide/hold on command FULLY LOADED
>>no other leg to support own self as load
.
Can paint broader to say all knots have such considerations that can be given,
But the friction hitch usage, with own life on the line; just exemplifies this more ; by demanding compliance
>>on much trickier riding a rail (host line) with full stops, rather than just a single position of open loop slide
>>and with own self on line an even more sensitive monitor of all!
So think, friction hitch just reveals more of 'sleeper facts' of all knots, once we must scrutinize this so close here
>>especially with life on the line

.