I Built a Transparent Katana

have you ever seen an invisible

sword well I think I have a few days ago

I saw this picture right here that is an

invisible sword and now I want one just

like that a sword that's not all

invisible but also destructible and

sharp a sword that's basically like a

normal one but that you can't see I'm

going to build one not sure how yet I'm

going to have to figure it out and then

I'm going to test its sharpness and

durability against increasingly harder

targets the first step was choosing the

right material and the first one that

popped into my head well it was glass

glass is transparent when it's cleaner

than that and you can make it pretty

sharp by using a diamond Stone like it

did here but even though there are some

kinds of glass that can be more

resistant than usual and even

indestructible according to the

companies that sell them the problem

with glass is that glass is

glass and glass breaks at least way too

easily to make a katana out of it but

there is another material that not only

is transparent but it's 10 times more

impact resistant than steel by weight

I'm talking about polycarbonate it is

generally used for riot shields armored

vehicles safety glasses and other

indestructible items and because of all

that it sounds like the perfect material

for the job but I kind of still want to

see for myself how hard it actually is

to find that out I'm carrying out a

small sample from the panel I'm planning

to use for the katana and the idea is to

hit H the polycarbonate as hard as I can

with this unnecessarily big

Sledgehammer 3 2

[Applause]

1 and well I'm not exactly sure what

just happened I only know that even

though B saw horses broke because of the

impact the polycarbonate panel is

completely fine this thing has one

scratch but you can't even feel it it's

not even bended or anything it's like

insane and since polycarb is clearly

resilient meaning it can bend like a lot

without breaking it's definitely my best

option so to make the katana I got a big

panel of polycarbonate 2 m by 0.5 and 12

mm or 0.47 in Stick which is also the

maximum thickness I could find for this

material and this is going to be the

invisible and indestructible body of the

sword now to cut the right shape out of

the panel I'm going to use tape what I

mean is that tape should make it easier

to draw the consistent curve of the

katana on the panel and then I can use

that as a reference for the actual cut

and after outlining the tip the edge and

completing the handle I can start to see

the final shape of the sword there is

just one thing to point out I

involuntarily made this thing big like

way too big it's basically twice as

large as a normal Katana and I'm not

sure if I should be excited because the

katana is massive and it's going to be

powerful or worried because the katana

is massive and I might not be able to

even lifted but after making a few

scientific tests I realized that because

polycarbonate is so much lighter than

steel it shouldn't be a problem to swing

the sword even if it's that big and so

I'm not worried anymore I'm just really

excited instead then I use a jigsaw to C

out a smaller perimeter around the sword

so that it's going to be easier to work

with it in the next step and after doing

that it became even more noticeable how

big this thing is going to be now the

next step is to crop the actual shape of

the sword out of the panel and and to do

that I'm going to use a b saw then after

cutting the shape I can remove the

protective film and I'm going to be able

to see if the sword actually looks

invisible the problem is that Ben sace

don't look too friendly and most

importantly I don't exactly know how to

use one so I got pretty

nervous

uh I already cut one part I forgot to

film I cut it really bad you see the

good thing is that I need to follow the

in interor line this part inside here so

my terrible cut wasn't actually a big

deal for now then I cut the extra

material out of the other side of the

katana and like that I was getting

closer now comes the hardest part I need

to follow these lines here and be

precise now this is definitely scarier

and I don't mind my fingers being close

to a deadly saw but making a mistake

here means removing material out of the

final Katana and potentially having to

start from zero luckily though I was

getting the hang of it and after

removing the extra material from the

handle I'm fixing the final details on

the Belt grinder as you can clearly see

here anyways like that the first step to

make the sword is complete I'm also

happy to see the weight of the katana is

not a problem at all it's not too light

not too heavy and the katana is not

bending on itself which means I'm

definitely on the right track and now a

few seconds of Silence while I remove

the plastic wrap

now the sword looks pretty invisible

already but inside the shop the effect

is actually weaker because of the lights

like in real life like like this it's

completely transparent for me

wait what if I do this

and that was already more like it or

less like it but outside it gets even

better bear in mind you can still see

the edges because there is no blade and

the spine is not polished so it might be

that the katana also looks darker

because the edges block the light but

when the edges are perfectly

perpendicular to the camera this thing

looks fake the effect is even stronger

when there is light behind it and I'm

very excited to see what this Katana is

going to look look like when it's

done I'm going to get this thing sharp

then I'm going to make the handle and

then I'm going to test it

against a lot of

stuff the first step to get the sword

sharp is to create a bevel on the blade

so after marking the center of the blade

using a caliper I'm retracing the line

with a pencil this line is going to be

my reference for the edge while grinding

also to make sure I'm going to grind the

blade symmetrically on both sides

basically like this I made this tool

this mechanism allows me to set a

certain angle so that when I grind the

sword with a belt grinder the angle

should stay consistent as well as the

bevel on both sides and this is all

Theory by the way I've never grinded

almost anything in my life and this

could honestly mess up the entire sword

but of course there is only one way to

find

out and well even though I felt like I

was doing everything wrong at the

beginning after basically 1 hour of

grinding the first side of the bevel was

completed and besides making an absolute

mess everywhere including on my face I

think it came out bad but much better

than expected and so after repeating the

process on the other side of the blade

the rush shape of the sword is done the

katana is not sharp yet but it has an

edge now and so the next step is going

to be making it invisible to do that I'm

going to smooth out the angle between

the spine and the bevel mainly to

prevent Reflections like the ones you

see here and while doing so I'm going to

also remove the scratches I got from the

belt grinder and hopefully turn turned

the katana even more transparent than

how it was before so I got a sander with

eight different bads from a course crit

to basically a polishing one and by

sending the katana with each one of the

pads in theory I'm going to be able to

make it transparent and well after a

little more than 2 hours I was basically

done with a first pad anyways I made

sure to remove every single scratch from

the belt grinder and even after just the