Should I just try it? Should I just swing my arm right through?
You didn't think I was actually going to show you that in the first five seconds of the video...
Don't worry, it does happen though.
So in case you've been living under a rock,
Disney recently announced that they've created
the world's first retractable lightsaber
which is kind of strange considering I have
a certificate right here from last year.
Ok ok so ours is still technically a proto lightsaber since it requires a backpack
but we are actually working on a newer version that might just be
fully self-contained in the hilt.
But more on that later.
So has Disney really made a real working, fully in the handle
gosh darn, laser beaming, plasma cutting, lightsaber?
Well probably not it's actually probably similar to the toy lightsabers that I grew up with.
In fact they actually filed a patent a few years ago about it,
but of course patents are always a little confusing to read.
And if you're looking at this with an untrained eye
you might be like "yeah this is a lightsaber, cool"
but if you look a bit closer it's pretty obvious it won't be cutting through anything anytime soon.
Luckily benriddout on Twitter created an animation
that kind of explains the rough concept of this patent.
And it's pretty cool.
I just hope the LED's they're using are super bright because if they are
it will be the most realistic and coolest extendable prop lightsaber on the market.
Anyway let's talk about the closest thing to a real lightsaber on the market.
Well I guess it's not really on the market since we're not willing to sell it...
But I'm talking about our current proto saber.
In celebration of May the 4th be with you
we thought this would be a good time to answer a few more questions about our lightsaber
and maybe try a few new tests including putting a hand through it.
Which we'll do at some point in this video.
Our original lightsaber video is now our fourth most viewed
video on the channel with over 31 million views!
That's absolutely insane!
If you add up all the views of all our lightsaber videos it's over a hundred million views!
You guys must like lightsabers or something.
So let's take a deep dive and talk a bit more about how this actually works,
what it can and can't do, and touch on how we're going to make it better for the future.
As we mentioned in the build video the basic principle of
a proto-saber is burning a mixture of laminar flow gas.
In this case propane and oxygen.
It's not creating pure plasma but there is a certain amount of plasma in the burning blade.
What makes it possible is the laminar flow nozzle which is from GTT glass torch technologies.
That's right the secret to our proto-saber is a piece of tech that's been around for decades!
And I guarantee anyone who's ever used or seen a
glassblowing torch has probably waved it around humming lightsaber sounds.
The cool thing is we're actually going to be working with GTT
to develop a new type of torch more suitable for our lightsaber-like application
which might just be the key in being able to make one of these fully cordless...maybe.
Either way make sure you subscribe.
So what are the biggest issues with our design?
Well for starters it's a proto-saver and having a cord is kind of lame.
But we've explained in past episodes one of the biggest issues with a real lightsaber is
getting enough energy into such a small hilt.
It's just one of those things that you know is limited by our technology of the time.
Maybe someday though.
The other big issue that lots of people pointed out is how the length of the blade kind of varies.
Since it is a torch flame it's susceptible to having its gas flow disrupted like this.
When it's pointed straight up we can get a blade
length of almost three feet or around 100 centimeters,
but when moved fast the blade can shrink down to a foot or about 30 centimeters
making swinging a lightsaber around kind of difficult.
Now the thing I'm curious about is if it's air resistance that causes this,
what if I use this lightsaber in outer space?
I'm probably not going to be able to try that anytime soon but what
if I could test it out in a large enough vacuum chamber?
Hypothetically since this lightsaber provides its own oxygen it doesn't need air to work,
and if it's the surrounding air that's causing this disruption of gas
you might be able to swing this around in a vacuum chamber without the blade changing at all
which would be really cool.
The issue is, where do we find a giant vacuum chamber that we can put this in besides like NASA?
Seriously if any of you guys know of a vacuum chamber that this could be tested in
let us know and send us an email at contact@thehacksmith.com.
A lot of people also asked what are lightsaber sounds like without any added lightsaber sounds...
and well this is what it sounds like...
it basically sounds like a louder version of a mini saber blowtorch.
Which honestly is probably what a real lightsaber would sound like
if a real lightsaber is in fact plasma.
It would make some noises not unlike that of a real lightsaber is.
In fact, a laser well it probably wouldn't make any sounds at all.
Okay now what about cutting power.
In the movies lightsabers can swing quickly through things cutting them instantly.
Unfortunately in real life we have to deal with a branch of physics called thermodynamics.
Specifically heat transfer.
Have I lost you yet?
Let's start with a basic example.
Take a tea kettle for instance.
Water boils at 100 degrees Celsius.
A tea kettle heating element can heat up to 100 degrees Celsius,
but water doesn't just boil instantly when you turn on the kettle or when you blast fire.
You see it takes a few minutes.
That's because the heat created from the element needs to transfer into the water.
In order to heat it up or in the case of a light saber,
how long does it take for the heat from
the light saber to heat up the material to its melting point,
at which point it would start to cut?
So how do we figure out how long that takes using specific heat capacity?
The specific heat capacity of material is the energy required to raise one kilogram
of the material by one degree Celsius.
The specific heat capacity of water is about 4180 joules per kilogram Celsius.
A watt is a joule per second so how long does it take to boil water?
Well let's try out the calculation.
If we take one kilogram of water which would
be one liter since water is a kilogram per liter in density
and it has a specific heat capacity of 4180 joules per kilogram Celsius.
We want to hit 100 degrees Celsius and it starts at room temperature or about 20 degrees.
Therefore the calculation is one kilogram times 4180 times 80 degrees Celsius
which equals 334 400 joules which means
in order to have a kettle boil a liter of water in just one second
you would need 334.4 kilowatts of heating power!
Remember the average North American home only has about 48 kilowatts of power for the entire house!
Luckily no one needs to boil water instantly.
Even our original tungsten titanium proto lightsaber which was essentially a giant 20
kilowatt heating element well it would take that 16.7 seconds to boil a liter of water.
It's fast but it's definitely not instant
so if you want to boil a liter of water in a minute we can divide
this total power by 60 seconds which will only be 5.56 kilowatts.
Quite a bit more reasonable but the average kettle is only 1.5 kilowatts
because of the limitation from an outlet.
At 1.5 kilowatts of heating power it would take the average kettle about
3.71 minutes to boil an entire kilogram of water
so yeah it takes a while to heat things up.
Luckily water actually has a really really
really high specific heat capacity while water's around 4200.
Steel is only 420 or a tenth of water.
That's great right, that means you can slice through a wall of steel 10
times faster than boiling a wall of water. Right?
That doesn't even make any sense.
Anyway for those that didn't listen to my physics explanation,
is it takes a long time to transfer heat into an object or cut an object with a lightsaber.
The only things we can control to speed it up is
the temperature of the lightsaber or the melting point of the material,
or the amount of material.
So yeah we can cut through a sheet of thin lead
quite quickly since it has a lower melting point than steel,
but there's less material to heat up.
And it's not steel, so the real question is how hot could we get a lightsaber?
Well I'm off, I'll be back in a couple days.
What? Where are you going?
I'm going to Japan. Anime.
What those like Japanese cartoons?
Have you?
I know what anime is.
Owen why are you going to Japan?
Well because they have stuff on Netflix that we don't have here.
I can't get it here.
You kidding me?
What?
Just install NORDvpn on whatever device you're using for streaming.
Whether it's a computer, your phone, or a laptop.
What's a vpn? Is that some type of like animated streaming service I've never heard of?
It's a vpn, a virtual private network.
It's super simple. One click that's all.
Open the map click on a location and you'll be connected in seconds.
It's that easy!
You'll have access to all the Netflix content
available in Japan or in over 50 countries without leaving home!
Damn.
I already got a ticket though, is it fast because I hate chunky video...
It's the fastest vpn out there and it also offers a cool anti-malware tool called cybersec.
You can be in Japan on your phone while you're on the bus on your way home
while even protecting yourself from hackers
and bad people trying to read your sensitive information.
I heard the wi-fi on those buses aren't so safe man and that goes for you guys too!
Visit NORDvpn using my link below or use the coupon code hacksmith
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They offer a 30 day money back guarantee
and they're doing their final sale at the moment so get going.
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So how hot could we get our lightsaber?
Our current saber clocks in at an impressive 2200 Celsius or about 4 000 Fahrenheit.
Using the current fuel mixture an acetylene torch can hit about 6200 Fahrenheit or 3500 Celsius
which is hotter than most materials melting points.
Unfortunately there are some challenges in running oxy acetylene in a torch like this
which is why we use propane instead.
Anyway the issue is even at those massive temperatures
we still need to take into account heat transfer.
A focused oxy acetylene torch can cut through steel plate fairly quickly,
but part of the reason that works is because a cutting torch is good at cutting.
It's because it has a very thin blade which means
it only needs to heat up a small amount of material,
which means it can cut things a lot faster.
Even though our lightsaber is hella hot it's got a big blade
and that means the heat isn't very focused when cutting things.
It has to heat up a lot of material before it can start cutting
and unfortunately that's just the reality of lightsaber physics.
In fact the only time lightsabers were portrayed in a reasonable way
was when Qui-gon Jinn cut through the blast shield doors.
It actually showed that it took time to heat up that much dura steel in order to cut through.
Even though every other depiction of a lightsaber shows it either cutting
through things instantly or in the case of vesgar not at all.
Our lightsaber could cut through a few inches
of steel plate it'd just take a really really really long time.
If we wanted to be able to slice through things and cut
metal just like the movies I'd guess that our lightsaber
would have to be in excess of twenty thousand degrees Celsius
aka four times hotter than the surface of the sun!
We could even do some calculations with our handy dandy specific heat transfer equation
but why bother if the blade is 20 000 degrees Celsius.
You wouldn't even be able to hold the lightsaber.
Okay back to our other lightsaber questions...
Lots of you guys asked if it would be possible to put some kind of solid blade
inside of our lightsaber so it could actually deflect another lightsaber.
Now that could work but the issue is
most materials that are capable of withstanding this heat
are also rather brittle which means it might work but you'd still have to gently
hit lightsabers against each other which is also kind of lame.
A lot of people also asked
what would happen if you shot a bullet through the lightsaber, would the bullet melt?
Well no, no it wouldn't.
And again we can thank heat transfer for the answer.
Since a bullet would be moving super fast through the blade I would guess
that it wouldn't even warm up because it spends so little time inside of the heat source.
But hey let's prove it. I'm going to use a nerf gun for our demonstration.
Though now a nerf dart has a very very very very low melting point
and it travels a lot slower than a bullet.
So first off let's see what happens if we put this into the lightsaber.
And it's gone.
Now that happened pretty quick, but the question is what if I shoot the nerf dart?
Not even warm.
And that's that's heat transfer for you.
Because it moved so quickly it didn't actually take on much heat from the lightsaber.
I guess lightsabers aren't actually very good at deflecting things or even melting things.
Alright that was kind of disappointing, but was to be expected.
So let's get to the real meat and potatoes of this video, the reason you clicked on this video.
Would this lightsaber cut off my hand?
Should I just try it? Should I just swing my arm right through?
So like we learned as long as I can minimize my hands time inside the lightsaber blade
hypothetically I won't cut my hand off.
My skin and body have their own specific heat capacities.
Though the human body's ability to self regulate temperatures kind of changes that
it takes a long time obviously.
A dead hand might actually be a more scientific test...maybe.
Yeah it's a box of hands.
In all seriousness though these are actually wax
hands from Ripley's Believe It or Not museum in Orlando.
A big thank you to Kurtis to sending these to us for our lightsaber tests
which well you get your wish.
We're gonna we're gonna see what happens.
Alright okay for the first test we're gonna slowly put this hand through and see what happens.
Whoo.
That still takes a while but that would most certainly be a
third degree burn or a fourth degree burn.
Is there such a thing as a fifth degree burn?
It definitely burns the hand but what if we swung the hand through quickly?
And this one...this one has hair on it so let's see what happens if I swing this
through the lightsaber really quickly?
Is it going to heat up is it going to melt at all?
And depending on the result is that going to give me the confidence required
to swing my own hand through the lightsaber?
Here we go karate chopping a lightsaber.
Um not even not even warm.
Let's uh let's do it upside down see if we can burn some of these hairs off.
Even the hair
Alright so this can't be overstated do not try this at home.
I am a trained professional idiot and uh yeah
based on my calculations everything should be fine.
You guys ready?
uh
Alright that was awesome!
Did you see how the flame wrapped around my hand and through my fingers?
And I didn't even get burnt!
That's because the time my hand spent in the actual fire
wasn't long enough for the heat to transfer into my skin.
Regardless do not try that at home, don't try sticking your hand in fire
just to see if you can.
If you end up holding it in for just a bit too long you could end up with serious burns.
This was a risk, it was a calculated risk on my part and I'm a trained professional.
But don't try this at home.
I hope you guys enjoyed this video and maybe learned a thing or two about physics.
We're going to keep working on our lightsaber technology so make sure you subscribe.
Because our next version of this, well maybe not the next version.
We're going to try and make it fully cordless which would be really cool.
And also make sure you keep your eyes peeled at hacksmith.store
because we're releasing our very own mini saber.
Thanks for watching guys!