The Last Unsolved Problem of Climbing Ropes

three two one

go this is the video about the last

unsolved problem of climbing

ropes it's a deep dive into the science

behind robe development in and out in

and out and

testing including the microscopic world

of rope failures some new exciting

Technologies you do not

load the cut resistant fiber and me H

any any last

words

uh volunteering to do some human

testing nowadays ropes are almost

unbreakable so that's good for your fear

of falling but what we are about to

talk might not be so great yeah this is

a standard test of climbing

ropes a steel mass is dropped from

almost 5 m causing the forces more than

double of what you can achieve in real

life cuz it's unbreakable if you try to

literally break it if you pull on it

there is almost no chance that it will

snap no but first your back will

snap but when we talk about cutting I

was surprised that till this day there

there is no standard for how cut

resistant rope needs to be and it's not

that hard to cut the rope under tension

which means that there is no

standardized test which would measure

how good the Rope is against situations

like

this I mean it's not like no one worked

on it uh it's it's a really difficult

topic and a lot of institutes

manufacturers notified bodies and

Laboratories worked on that

now before we start breaking ropes a

quick detour to the 19th century the

early days of climbing with the best

advice you would get back then is that

the leader must not fall we used hemp

propes made for agricultural purposes

that had almost no stretch so if you

fall you either going to break your rope

or your ribs shall we go climbing

I brought some ropes brand new smells

organic want to take a whip on it are we

doing some uh test falls on

this not sure you want to now as you can

imagine these agricultural ropes didn't

had much quality control and that's why

in

1862 this serious looking Swiss man

decided to bring Swiss quality to

climbing ropes and here mammut was born

a year later followed by a German

company Eder and multiple Decades of

craziest

climbing

yeah now in 1935 everything started to

change when the chemical company dupond

invented nylon world's first synthetic

fiber yes boys this is it this is a

synthetic fiber you mean we make cloth

out of that yes we do actually to make

nylon you only need two components acid

and this thing that I cannot pronounce

so then I'm going to reach in here and

where the interface is I'm going to pull

out some nylon so here we go now we'll

see how much nylon we can pull out of

this

thing there's a meter or

so two so on a large scale this is done

not with a whole bunch of people doing

this of course

but by the way take a guess who was the

first user of such great

material certainly is a long time since

we've seen legs looking like that

perhaps I should say stocking was

looking like that that's right women

they love nylon stalking so much that

they gathered in crowds real Nyon and

fully fashioned very nice to see again

from any

angle and then World War II broke out

due to the conflict with Japan United

States lost access to Silk suppliers so

military needed to transition all silk

products like parachutes to nylon which

greatly accelerated development of nylon

but women felt the shortages but no

worries you can always paint legs to

look like they have stockings turned out

to be a great

business after the war nylon found its

way to Europe and mammut launched a rope

which can actually stretch but a year

later Eder invented the C mantle

technology which was an even bigger

Revolution it's a little bit funny

because a reed invented the kmle r the

owner of Mamud was not really convinced

by the New Concept he wanted to stick to

the Twisted one and just a couple years

later um M would also launch the first

ctal Rob so very quickly realized that

oh that's actually a good idea yes curl

mantle ropes are made out of two

components the core strands that are

twisted and the shift which is braided

around to protect the

core okay keep going keep going very

expensive rope with my uh with my hourly

pay okay so you have two different types

of spools here the red one run into this

direction by Red we mean this yeah the

red one go counter clockwise and the

yellow ones clockwise and they always go

in and out in and out in order to create

the

braid it's actually quite cool to see

this if you look at the core strands

from Modern climbing ropes they also

have this kind of twist this is like

exactly the same as this in theory yes

why is there many core strands and not

one big core strand Twisted together

that's a good question we have cores

that go in s direction that are twisted

in One Direction and other cores that

are twisted in the other direction this

is something that is a reoccurring theme

in the twines that are used in a rope

that you always differ the direction to

kind of work against the

natural uh motion of twisting now back

in the days when the military was

testing parachute deployment we noticed

that forces higher than 15g can result

in injuries to The Spine and Neck and

since climbers also don't like breaking

their backs they decided to borrow that

limit when the uiaa standard was

developed the developers back in the day

said it's impossible to reach the limit

of the 12 kons that is interesting that

at first we came up with the standard

that nobody could achieve and then only

later we managed to achieve it okay in

1964 we we got the first rope that is

certified to not break our backs and now

80 years later and we're still using the

same curl mantle technology which is

kind of impressive but what's not

impressive that till this day our ropes

still have the last unsolved problem

that they are not that hard to cut

especially when they are under tension

give me some sharpish objects sharp edge

object sharpish sharpish

oh

good but that's so

tiny this is dangerous this bringing a

knife and a file so we have a

file which is uh it's a metal file we

have a knife and this

thing in k no I will start with a dull

one and if it turns out to be too much

work I will go to sharper one so at

first we pull the Rope to 80 kg this

imitates a climber simply hanging on the

Rope oh wow it's not that hard to

cut

and yeah this file is not that sharp

kind of

[Music]

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scary no show

not as spectacular as you'd hit what I

want to actually now

try Okay significantly

harder yeah if it's like completely

relaxed

huh train you got really red

dude I just wanted to see how much

harder it is to cut not underload so

let's try what happens at

3.5 kons it's a hard fall load let's go

do I need the safety something you think

I'm going to die at three no no five

have you tried this before

no are you brave enough is the question

now my camera man is going

away you

ready yeah I'm

not it said something it wants to

talk let adjusting to the

weight it's War wow I'm barely barely

doing anything oh now be careful with

your fingers

[Music]

I think it

will wow I barely touched it so as you

can see tension in ropes plays a big

role in Cut resistance and now some of

you might be thinking why can't we

simply add some kind of material in the

Rope which would make them much harder

to cut well we do have ropes that are

made out of the Nema and aramite okay so

this is a glacier cord and where is it

used it's for securing yourself against

faults in a crass if you would fall in

there you have covered with snow so the

snow kind of dampens the Fall mhm so

this is why you don't need the Dynamics

in this type of rope this is a shoelace

yeah 6 mm is this dyo or yeah on the

inside it's a dyema on the outside it's

a polyester AR and this Glacier people

came up with a thought that it's okay to

fall on this well cuz you don't fall

well then don't use it so we put this

cord in a drop tower with relatively

small amount of slack and we wanted to

see what happens when you apply a

dynamic load on the super strong yet

stiff

material oh my God it's always so loud

in here what was the force 7.9 so what

force do you expect out of dynamic rope

on the same fall m I would say around

3.6 3.7 3.5 so 3.6 and 3.5 want to play

some bets what's your guess 3 kilon

Neons okay he's paying for

dinner no the closest one p for the

[Laughter]

dinner

[Music]

what okay so I'm playing for the dinner

so as you can see material which is

rated for 14 kiltons for a static

scenario broke at around 8 in a dynamic

drop which is a peculiar observation on

itself but that also shows that

incorporating these super strong

materials into Dynamic climbing ropes is

not that trivial now the second problem

comes from saying that if you can't

measure it you can't improve it and

turns out that measuring cut resistancy

in climbing ropes is a very tricky top

IPC in 2002 UAA proposed a test similar

to a standard drop test but here the

Rope was falling over a sharp edge but

the problem was the values that we got

or the values that they got back then

were just inconsistent within the test

but also between different institutes

and Laboratories so 2 years later the

test was withdrawn and since then a lot

of different tests were tried out by

different organizations and mammut also

also had their own idea it's a pendulum

swing with a sharp knife is dropped onto

a pre-loaded rope so instead of the Rope

falling with the weight you had rope

static and the knife was falling exactly

the knife was falling and you measured

how high the knife came after the

cutting and then you could calculate how

much energy was necessary to cut it so

we worked three years on that but at

some point we also had to say yeah it's

giving inconsistent values opened more

questions than now the common problem

with many of those tests were that

either the forces were unrealistically

high or the Dynamics in those test

introduced too much variability meaning

when the Rope is falling on some kind of

sharp edge it will never fall in exactly

the same way so in 2018 edet proposed a

slightly different approach where they

eliminated all the Dynamics here the

rope is tensioned to desired load and

then the discs spins and cuts the Rope

and the Machine is measuring how far the

disc had to travel to cut the rope in

2015 there was an accident where two

people were lowered on a single 8.7 mm

rope the Rope moved a bit over a sharp

edge and it was cut and since this test

reproduces the accident scenario really

well edet managed to answer a very

important question what had a bigger imp

impact in the accident the fact that

they used super thin 8.7 mm rope or that

they were lowered two people at the same

time first we loaded two different ropes

to 160 kg imitating two climbers hanging

and even though ropes had different

diameters the cut resistance was very

similar but then they took the same rope

but loaded it with different load and

this time the difference was much bigger

this shows that the load on the Rope has

a much bigger impact than the diameter

of the Rope so a great takeaway would be

to avoid practices where two people are

hanging on one strand of the Rope but at

the same time 160 kilos that we used is

not that much when we start talking

about Dynamic scenarios their forces can

reach up to 4

kons and also the cutting patterns

become way more more complicated

recently there was a very interesting

paper published which took ropes that

were cut and looked through the

microscope and what they found was four

dominating patterns the first one was a

clean cut the second one was a tiered

cut as if you would be cutting with a

dual knife then they found some

mushrooms these happened from high-speed

fiber overload and lastly molten fibers

and then we looked what p patterns they

will find in ropes cut by different

tests starting with ederly disc which

produced a lot of Clean Cuts but also a

lot of tiered Cuts this probably

happened because the disc actually has

these small teeth next they looked into

the old mammut test and this one was

pretty much dominated by mushrooms and

the possible explanation is because the

Rope was tensioned to unrealistically

high Force

and of course I had a question why

didn't we use more realistic loads on

this test when we lowered the preloading

to 3 4 Kon then uh some of these ropes

have not been able to be cut we were not

able to compare the results you wanted

that all the ropes will be cut but then

you can measure how much it takes that

was the difficulty of the test yeah okay

next we looked into the old uiaa test

and here we found a lot of mushrooms but

also a lot of molten fiber

and finally they simulated a realistic

Dynamic scenario where the Rope was

running across a sharp granite edge and

also they compar the patterns in

different parts of the Rope like The

Shift versus the core and after all the

analysis the study concluded that no

test method can fully replicate the

complex breaking mechanism observed

during an accident

simulation so yeah a deep rap hole but

this brings us to the best part of this

video ah fancy this thing can go up and

down yeah you don't like walking ladders

so you made the machine which goes up

and down Dano was climbing this Ladder

Up and Down millions of times it kind of

feels that it grabs the edge but it's

not like super cut yeah I mean I

wouldn't even think outside that this is

an issue there sever edges out in the

mountains that are much sharper than

this yeah so if we do the tests then you

will be afraid of climbing after

it here you have this 45° surface so

it's like 90° and then 45° cut yes cut

yeah yeah so it's not actually like a

pointy Edge it's relatively rounded Edge

but the granite has this roughness to it

yes I would say so let me get the reason

we cannot make this standardized is

because it's impossible to make this

granite edge standard like yeah so this

test setup is not something that aims to

be a standardized test method that needs

to be reproducible in different places

so you need that exact same granite edge

at in 10 different places this was not

the goal it was for us in the

development to learn how different

constructions are behaving thicker

diameters thinner diameters different

shth con instructions just to get an

insight for that okay ready 3 2 one and

go 1

go well I wouldn't want to be a climber

in this case Qui cut quiet cut that's a

quiet cut um 3 2 1 go

W and this one's friend holding

on yeah but it's just being pulled out

it's not holding anymore huh so you can

see where the cor strs were

cut we have one left it was completely

pulled out this is the original end and

you can see the whole that remains and

how hard is the fall what's the force to

the climber I would say it's a realistic

fall with realistic forces 3 kiltons or

300

kog all right our first rope was failing

very easily so we change to a thicker

one all right 3 2 1 go

[Music]

it's crazy cuz it looks like a tiny fall

and a tiny swing and it went yesterday

we basically spent the day breaking

ropes and yeah I I wouldn't have go

straight to the to the to the to the

Rock to climb because no wasn't the goal

to be the

opposite well it as a climber it kind of

scares you to see this a little yeah

that's that's true all right moving to

even thicker 9.9 mm rope 1

go wow that's quick you can see the

different types of cutting mechanisms

here first the chef has been cut and

then it kind of looks like the Rope is

remaining on one position but the load

is pulling more and more yeah you see

the cover the the course breaking one

after each other yeah so it's 3 seconds

for the whole rope to break it's quick

that's very quick mhm oh exciting so um

shall we

do okay let's do the thickest rope on

our list 3 2 one

go so I don't know who still buys such

monster

[Music]

ropes but I guess here you go that's for

your fear of fall fall ing the slow

motion

torture so yeah

subscribe and I promise that the Rope is

not going to

break come on the button is down

there we need

you thank you for subscribing you're the

best so as you can see while adding more

material and making the ropes thicker

does help a little bit it's not by much

and obviously mammut wouldn't be

inviting me just to show how all the

ropes are failing they actually been

working on something new ah so this is

the new row yes so it has an extra

something inside oh look at that I would

not even be able to guess that it's made

out of different material it feels also

kind of fabric soft I was thinking you I

will open this and we'll find some metal

inside no it's textile and the key

component is the intermediate Chief here

you have here a intermediate chief that

protects the core so normally ropes have

shift and then they have the core and

and this rope has one more sheath you

can say this intermediate sheath is made

of um high strength aramite fibers that

have an overlength so with this

overlength um they are free from tension

this is actually very interesting while

aramite is a super strong material

commonly used in safety equipment like

cut resistant gloves or bulletproof

vests however as we've seen before arite

is very

stiff so to solve this they needed to

create a design where nylon in the Rope

would stretch and absorb the impact but

aramide would stay without load this is

the so-called we call it the hybrid

Yan what is uh made of two different

fibers so this middle layer is not only

arite it's a hybrid yes okay and you see

that there is one with a longer yarn

inside yeah and one is sh okay so there

is two Thin strings one is completely

stretched now and the other one is

curled around the stretched one yes this

is the one with the over length if you

load it

now you do not

load the cut resistant fiber okay to

illustrate this is an elongation curve

of a pure nylon and this is a hybrid

yarn without an overlength so not good

good but by introducing an overlength in

aramite they managed to achieve a curve

like this so basically during the fall

you probably are not even going to feel

any difference on this rope no nice and

why is it hybrid inside why is it not

all armed it will not um be held in

position so you need anara because it

you have the overlength anywhere and if

you move with the Rope

the maybe it changes the place that's a

very smart design now it makes more

sense how does it come back after load

cuz otherwise you would stretch and then

the middle layer would move somewhere

but since you have some nylon in it it

will reset the middle layer probably as

well yes of course mhm now as a fun fact

this robe has only 4% of its weight in

aramite so let's see what that does

ready to Launch

3 two one go

[Music]

[Music]

who oh but the core it's only hanging on

the core strands yes middle sheath is

offering a protective layer so it's not

like the middle layer is indestructible

no no of course not a but the core

strands barely got any damage yeah just

a tiny bit Yeah so while this middle

layer was adding extra protection for

the Rope it was still eventually cut

right outside of the camera frame

sorry 3 2 one

go it's about does it hold in this

scenario or not mhm so we are kind of

deducting from this test setup that it

does perform significantly better than

normal inline rope with the same

diameter so if you look in keeping the

same weight of the rope and same handle

you will get an extra safety margin on

top but the thing is something that you

need to be aware of just because you

have an extra safety margin doesn't mean

it will absolutely not break this is

no so a very interesting design indeed

and while I'm still waiting for

completely indestructible middle

layer there was something that had

actually even bigger impact on the cut

resistance so instead of having the Rope

safely attached to the beam I came up

with a brilliant idea to attach it to

myself no I'm I'm curious if it will

break when I will be L yeah no I think

um it won't yeah because Dynamics also

play a big role so but let's say I I

panic as a bler and I take really hard

will it break that we will find

out so let's say

what I'm afraid is that I will jump and

I will end up there and then it will

break and I will fall yeah that would

suck CIA was nice to meet you H any any

last

words

um for science okay

ano I see some anxiety sweat PS go okay

3 2 1

so my plan was to take during the fall

and at the same time go down to cause as

hard catch as possible however since I

was belaying with a tube raising my hand

up was causing the Rope to slide through

the blay device way too much but the

Rope was still damaged now for the

second attempt I decided to not take and

just go down

okay so for the climber it was a force

of

2.98 so almost 3 kons in our previous

experiments where we had the Rope

attached to the beam ropes were breaking

at slightly higher forces so to match

that since now we have a little bit of

extra rope we decided to slightly

increase the fall

yeah you were too fast then so yeah I've

heard that dying is against YouTube

monetization policy especially in front

of so many cameras so I'm glad I didn't

but since my timing was meh let's try

again 2

1

[Applause]

yes I guess my climber did not VI that

was beautiful B where is my

climber it actually broke not on the

first impact I felt like I caught it and

then it was sliding and then it broke

and then I had like T and

P nice okay now we tried the same but I

will uh delay softly ready

y three 2 1 now for the soft catch since

I was belaying with the tube my idea was

to Simply let the Rope slide through it

however my timing was Mech again I

couldn't see the climber okay don't

judge huh

nothing that's so cool so first let me

give you the force 2.3 so 2.3 it's

really nothing huh it's so chronics

nothing nothing nothing nothing what not

even abrasion

what absolutely

nothing we the wrong

side yeah yeah it burned that is crazy

it just burned a little bit on top but I

would still climb with this rope yeah

totally I was almost sure that it will

not break but I was not expecting to the

difference to be that drastic yeah all

right so far we explore the dangers of

sharp rocks but another massive danger

comes from sharp climbing equipment this

is for example in the climbing gym in

the first caribiner oh the very very

first quick draw in the gym was sharp

and it cut somebody's rope mhm the Rope

went like like this in the Carabiner and

then up as you can imagine the climbing

gym and so it sharpened it in a really

bad way and for many many years maybe uh

no one Dropped In in the first Quick

Draw also no one inspected it in the gym

the person fell into the first Quick

Draw and then the the Rope ripped so

what is this test well we're cutting

ropes once again this time we're

dropping the ropes over a sharp

Carabiner it has a very sharp edge

actually yeah you would

notice if something like this would be

out there three two one

go you have to see this yeah it looks

again very violent my God that one that

was not something I was expecting 3 2 1

go

I think Bing it is oh it's so scary how

it goes like for like 2 3 seconds goes

zoom and then just boms it explodes now

assuming the Rope would not fail this

test was set to produce around 3 and A2

ktons to the climber so again imitating

real life

scenarios oh my God that happened

happens so fast it's not getting any

better right still

terrifying is it for you yeah it's

shocking honestly like it it's such a

violent

explosion horrible gives me nightmares

and 9.8 we

go wow the Rope uh it survived but it's

uh yeah it's pretty

damaged I want to show you something

because of this

impact you create so much

friction that actually this is like a

part that melted it's like a little cap

so this thing melted on the Carabiner

and then the rest of the Rope was just

going over it so it kind of created a

protective uh piece of material that the

rest of the Rope was sliding over this

rope we know that it can break but but

sometimes it can also hold so it's like

a little bit of a

[Music]

gamble all right next 10.2 mm monster

[Music]

rope so yeah sometimes more is better

but in case you want

less here is a new construction

rope first it cut through the outer shf

it failed here but the sharp edge was

traveling along the longitudinal side of

the rope and kept on damaging but there

um the middle Chef was protecting the co

strand so this was good the craziest

thing that this is this is fabric this

is textile mhm and we are falling on it

and it's holding and comes back like

this coming back is always the most

fascinating thing for me if you load it

and you put it on the table and you see

it shrinking back slowly it lives H you

should name your rope you can write a

comment what name you give to your rope

we're curious the name with the most up

votes will get a free rope from

mammut is that the case that' be cool

let just's make that happen okay yeah

that's that's

that so for whom is this

rope for a sailor for sailor a nice

wooden

boat yeah it matches

then ah we are talking not about this

we're talking about this rope so should

I buy this rope for going to the cracks

or it has a different intent for whom

this rope is actually mountaineering

Ridge climbing multi-pitch climbing

where yeah there are a lot of sharp

edges also maybe ice climbing is where

you maneuver with a lot of Sharp Tools

already single pitch climbing yeah sport

climbing Trad climbing do you really

need it I would say hey it depends on

the route why wouldn't I want this in a

crack will it last less long is it less

durable since the sheath is you said a

little bit thinner yeah so you have a

little bit less uh sheath since we had

to make room for the aramid uh shf did

you run this through your abrasion

testing machine yes we saw a decrease

but you know in German we have the

saying that you want theing Theo so you

want

and a a pig that has wool and is also

laying eggs so you want you want an a

all overall package that does not exist

so this is kind of the thing with robes

you can't have it all at once so that

was a journey which makes me really

curious to see what's coming next and

what rope names you going to put down in

the comments and also making this video

took me over 3 months many locations and

many smart humans helping

me so probably not the best strategy for

a successful YouTube business and it

would definitely not be possible without

kind people supporting me on my patreon

and in other

means so I send a lot of low gravity

days to these kind of people these kind

of kind people and thank you for

watching and see you in the next next

one