this is a dynamic climbing rope one can
take hundreds of these massive Falls and
it will still provide a soft Landing for
the climber Now Let's ignore the blue
protective shift and pull out the core
so this white strands is the core of the
Rope which is responsible for majority
of rope's strength if I would untwist
the core strand eventually I would get
to this thing which is called a
multi-filament and if I would dig deeper
and try to separate the smallest part of
the Rope I would get to a single
filament which I can barely see so this
is a single filament
so this filament is about 10 times
thinner than the human hair and there is
about 50 to 80
000 of them in a single rope and all of
them run across entire length of the
Rope now during the fall this filaments
stretch but also they slide past each
other which creates friction and this
friction helps to dampen the impact
however if we would make a rope wet
water on the surface of the filaments
would act as a lubricant this would
allow the filaments to slide easier past
each other which would reduce the
dampening effect also you can probably
imagine that as I want to stretch the
Rope out it needs to shrink in diameter
however if the Rope is full of water in
order to shrink in diameter first it
needs to spit the water out however if
the impact is hard enough the water
cannot Escape faster it's like when you
belly flop on the water and the water
doesn't have enough time to flow around
your body and things get even more
interesting from here if we would look
deeper deep deep inside the filament we
would find this but don't worry the only
thing you need to know that this is a
monomer which joins together to form a
polymer chain and this chain can be very
long very very long which is really
great for making filament fiber and this
is where things get interesting notice
that some parts of this fiber are
arranged neatly in order these parts are
called crystalline and they have polymer
chains packed so close together that
they form an attraction for each other
and this happens because hydrogen from
one chain really likes the oxygen from
the other chain so all of this makes
these parts really strong with which is
great for the strength of the Rope
however it also makes these parts really
stiff which is not so great when you
want your dynamic rope to stretch and
that's what these other parts that look
like spaghettis are four they are called
amorphous and they have much bigger gaps
between the chains which allows them to
stretch
so when the force is applied on the
fiber these spaghetti Parts stretch and
the crystalline Parts provide the
strength you can probably imagine that a
very stiff rope
wouldn't be great for climbing but
neither the Rope which would stretch too
much because when I fall I want to land
not on the ground so by controlling the
ratio between spaghettis and crystalline
Parts rope manufacturers can create this
great strength but at the same time
perfect Force absorption which is quite
impressive now remember I said that
hydrogen really likes the oxygen guess
what else has a lot of hydrogen and
oxygen that's right water good news is
that water cannot really penetrate into
the crystalline parts of the fiber
because the chains there are very packed
close together already however spaghetti
Parts have gaps and that allows water to
come in and bond to the chains and this
bonding increases the distance between
the chains and it also weakens the
intermolecular attraction so now if the
the force is applied when the fiber is
wet spaghettis might stretch more than
what they are capable to recover from
and that might damage the entire
structure of the fiber but all of that
is in theory so let's see if that theory
applies to real world climbing
situations
[Music]
and if you're wondering who goes
climbing in the rain well this was my
birthday and we came up with a brilliant
idea to climb 34 routes in a day and
half of the day was raining
so yeah let's say I have some wet
experiences but my anecdotal experiences
are not science and to do proper science
I needed to go to the place where the
ropes are properly tested
[Music]
[ __ ] there's a lot coming out
[Music]
that's a lot
and before we begin a strange fact I
checked a lot of user manuals of dynamic
climbing ropes from various Brands and
about half of them have various warnings
about wet drops however the other half
doesn't mention anything
hmm okay so here is the question
will dry rope cause harder catch on
realistic fault scenario
well we would say over time yes in the
beginning probably not
so you mean on a first fall maybe not
yes and on the repeated Falls probably
yes exactly that's not my first
statement made
now since we wanted to mimic real world
scenarios
and heartfalls rarely exceed 4
kilonewtons we needed to modify the drop
tower to produce the forces between
three and four kilonewtons
so we overshoot yes we did buy a lot
[Music]
okay
which took a bit of adjustment on this
old drop tower Mammoth actually has a
way more advanced drop tower which I
already had a pleasure to use when we
were testing the cut resistance of the
ropes which was super interesting yeah
that's easier with the other one because
it works electronically you can put in
the number where you want to go and then
it's aligns it by itself but we are not
allowed to use it not for the water
it doesn't like water yeah so this one
doesn't like the water this one also
doesn't like weather no as soon as these
get wet rust will appear off the wall
and then friction has a big influence on
the yeah but this one we don't use this
for any development or production
control yeah that's why we are allowed
to make it wet exactly
4.11
[Music]
I've heard you're going like oh
the frustration
and not only we needed to make sure that
our samples are between three and four
kilonewtons but also that each of them
is as similar as possible how is it
going we have a method of how we can
always make the nuts equal later we will
have fun
it's a group activity it's a team
building yes how many samples do we need
depends on you how many samples do we
need
depends on how many people we have
making them
[Music]
so what's going on equal length is equal
everything is equal having samples as
similar as possible was actually really
important because as Adriana said
textiles is a very tricky and Moody raw
material to work with Moody it's very
moody yes so although we cannot control
the mood of the Rope but in order to
make the nice statistics that you're
gonna see later in this video we needed
to try our best
too long so basically we are massaging
back and forth to get uh yeah it's what
we in German call it Sisyphus are bite
no we got it you think so if not it's
time for lunch
either we succeed or we eat
everybody click
three points
yeah when I was editing this I thought
wow if you ever wondered how Geeks are
celebrating life this is a prime example
anyway the next question was is our test
setup repeatable meaning will we get
second fall to be close to the first one
if we don't get that then we five hours
more
don't make a night session work till
five and then you go bouldering we have
time limit
because we need to go bouldering because
we need to completely
very nice that's very good very Swiss
accurate
our setup was working really well and
now we needed to collect a lot of data
this might take if we wait three minutes
and we do five Falls that's 15 minutes
just waiting times three times six
fifteen
I the eyes are getting bigger and bigger
and here are the results if we average
all the samples we get the Baseline of
how the force is increasing with every
fall which shows that rope doesn't have
enough time to fully recover so let's
see what happens when the ropes are wet
look how much air is coming out
all the air is escaping from the Rope
during the fall the water will be trying
to escape trying to blast out of Europe
we wanted to do three different tests
where the ropes were soaked for 1 5 and
15 minutes and what was interesting that
fully submerging the Rope for just one
minute was enough to almost completely
saturate the Rope meaning that soaking
for longer did not add any extra weight
and after we dropped all the wet samples
and enjoyed the splashing of the water
everywhere
[Laughter]
oh my God
here are the results since the
difference in water absorption was
minimal the forces were actually very
similar and if we take the average of
all the wet samples we can see that the
first fall was only slightly harder
however the difference increases with
the subsequent false
you know it's combining everything to
family so statistically significant
very good today we made a page
science a little future me Interruption
since I got more information the peak
forces that we measured obviously do
contribute to how hard the catch will be
for the climber however it's not the
only Factor
the big Force to the climber usually
happens around this moment but even on
the hardest Falls this moment is not
hard enough for the human body to be a
problem what is the problem however is
how hard the climber will hit the wall
as I mentioned earlier as the Rope is
stretching the filaments are rubbing
against each other which dampens the
energy and and if the Rope would be able
to absorb all the energy during the fall
it would stretch and then stop however
that's not what happens on hard Falls
normally the Rope will act like a spring
it will stretch and then bounce back
that bounce back usually creates more
energy going towards the wall and if the
Rope is wet the filaments are sliding
easier past each other which reduces the
dampening effect so the bounce back into
the wall should be harder so I was
really curious to test this however this
requires more advanced testing
facilities but luckily after I left
Mahmoud did this test in another
facility and sent me the results here is
the force graph where the initial Peak
was said to be around 3.6 kilonewtons
and after that we can see how the Rope
bounces couple of times now in the case
of the wet rope the peak is only
slightly higher however the spring
effect is much higher and this is the
same graph after five consecutive Falls
the initial Peak was 23 percent harder
however the bounce was much harder so
the spring effect was much bigger
alright so far we confirmed that wet
robes might cause harder Falls but also
according to the theory wet drops might
lead to some permanent damage to the
Rope
let's see so we left the last rope
hanging overnight
so technically now it's dry and
um and rested
so we dropped this rope once again and
the fall was harder compared to the
Baseline which definitely hints that
there was some permanent damage done to
the Rope alright so far so good and
there was two more experiments I wanted
to make first of all we did all our
tests on classic ropes so I was curious
how dried treated ropes would perform on
the same tests and in case you don't
know dry treated ropes are soaked in
certain chemicals that make them more
water resistant our dry ropes we add the
chemical first to the core so to the
strands they get a drop application then
we braid the rope together and then we
submerge it in a chemical bath and we
take it out and we dry it and then you
have a dry roll so basically core is
separately submerged into chemical and
then entire rope now the cooler get a
drop application you need
just a little drop every every couple
seconds is enough to make it uh water
resistant interesting and then the
entire rope goes into the thing yeah
when it's finished so let's see how good
that treatment is in practice
[Music]
so at first we did a lot of drops
without water and that allowed us to
compare treated tropes with classic ones
and it was good to see that treatment
has no negative effect when the ropes
are dry so let's see if it has a
positive effect when the ropes are wet
number two number two you want to get
the shot of how
treated robes Stone bubble or duvet
bubble wait maybe I don't want to
look it doesn't bubble as much as the
other one
what if you squeeze it a bit but no
squeezing
and yes dry treated ropes absorbed
significantly less water
ah I know what can be the problem that
ends I see bubbles coming from the ends
a little bit although we sealed the ends
but most of the bubbles are coming from
the tip of the Rope maybe I'm gonna keep
that tip just a little bit out
yeah I mean you can always have like
little holes where it could get in with
these kind of things if it's not seared
well in the end you have like a
capillary effect of that the water
traveled along the fiber okay let's see
I'm super curious
[Music]
wow there was no splash of water
and here is the treated rope that we
soaked for 15 minutes as you can see
there is still barely any water coming
out of it and if we would compare this
to the classic ropes the difference is
huge
we're still here collecting the data
Never Ending Story how are we feeling to
you
yeah
here stopped for climbing and when it
comes to the treated tropes soaking them
up to 5 minutes showed no increase in
forces however soaking for 15 minutes
already was worse but not as bad
compared to the classic ropes so dried
treated ropes unsurprisingly were
performing better in wet conditions
however I know that many of you myself
included had a question how long does
dry treatment stay effective does it
wear off so this is a used truck that I
used for about a year actively almost
climbing every second or every third day
so we could get a sample of this
yeah that's it this orange rope that I
brought is actually perfect for our
comparisons because it's exactly the
same rope as the one we already tested
the only difference is the color
at first we did the test without water
so that we could compare how much
stiffer old rope gets compared to the
new one and to my surprise the
difference was very minimal one note
here is that we selected the test sample
from the middle of the rope that part of
the Rope usually is the least damaged
but that's good to know that if your
ends of the Rope are damaged and you
chop them off the rest of the Rope
should perform really well
[Music]
yeah
oh it's bubbling much more than new
ropes yeah and yes old rope absorbed
more water however it still performed
better compared to the classic rope
being new treated rope soaked for five
minutes let's see how it how well it
served
[Laughter]
[Music]
we actually washed the Rope but you can
still see that the water which comes out
of it
is still grayish a little bit
coming out does it hurt so you want to
blend my washing machine
and this is what happened with the wet
old rope the first fall was actually
identical which is very nice and then
the subsequent folds again had an
increase in forces
and if we would compare all wet drops
this is what we get
and the only thing missing here that we
had no time to do would be to test old
classic robes
so yes treated robes do lose their water
repellent magic Over time however they
still perform better compared to the
classic ropes however there is still one
very interesting thing to know let's
look into water absorption graph again
notice that classic crops are almost
fully saturated after five minutes
however treated tropes even after 15
minutes still have a trend up so then
the question is what's the full
saturation point of treated ropes so I
asked Adriana to do these tests and here
are the results turns out that all the
ropes were trending to the same around
40 percent level so that means even if
your rope is dry treated and you put it
under water and you leave it there for
long enough
I don't know why would you do that but
if you would do that eventually all of
these tens of thousands of tiny
filaments in the Rope would act as
capillaries and the water would find its
way in and it would probably perform
similar to the Rope being not treated
now before some of you will become
hydrophobic let me add a couple of
things yes wet ropes are significantly
heavier which sucks when you're climbing
and they might wear down quicker both
from false and from abrasion which sucks
to your wallet also there is a theory
that They are thicker with swell from
water
let's see
I soaked this rope for a few hours this
is supposed to be 9.8 rope and I'm
measuring
11.3 let's see the wet spot
okay
so I don't see any difference at least
on this rope which is worn out and it's
already thicker when it's nominal value
yeah so I didn't want to leave my fellow
climbers hanging like that so the next
day I took a bunch of different used
ropes soaked them and measured the
thickness and what I found out is that
indeed some of the robes did got thicker
like the green decathlon rope for
example however other ropes did not
change in diameter next I tested how
smooth the ropes run through belaying
devices and here my findings were mixed
again some of the ropes got sticky they
became harder to pull through belaying
device and more likely to lock the blank
device however other ropes got the
opposite result they became more
slippery as if water would lubricate the
billeting device so yes the laying does
change with water however it's unclear
how how the change will affect Europe
and about those other things well
honestly it's unlikely that you will
climb in such a wet conditions long
enough to even have those problems so if
your rope got a bit wet well try it but
if I would be going to cold wet ice
climbing places where people die
um yeah maybe having a treated rope
reduces the chance of dying this is so
hard she put I mean I don't know just
like being in a snowy or icy environment
it's recommended to have the dry
treatment because it's just an extra
safety buffer yeah there is one route in
Spain which crosses a waterfall in
multi-pitch
yeah I mean also if you're climb in very
humid conditions it's Thailand
we go there it's really humid and dry
rope makes sense
interesting so the little details shall
we go to Thailand to do some science
research trip
all right if you found this video
interesting I made the playlist for you
where I was nerding with Mammoth
Engineers on different topics very
interesting topics so thank you Mahmoud
for letting me to periodically come over
and play with your toys and thank you
Adriana for all their rope chemistry
explanations and thank you for watching
you in the next one