- Oh, hi. I'm Gav. - I'm Dan.
Welcome to the "Super Slow Show."
Dan, have you ever wanted to see your name in lights, big lights?
Well, who hasn't, really?
Yeah.
Sadly, couldn't find any light bulbs
but did find a load of det cord.
( theme music playing )
I love that we have that in the shed and not lights.
- It's a very Slow Mo Guys problem to have. - True.
And you used to use det cord in the Army, didn't you?
- Yeah. - What's it all about?
Well, basically, it's called detonating cord. It detonates, right?
About 6,000 meters a second. Which is super quick.
- God! - So in the blink of an eye, it's gone.
It's like off into the horizon in one second.
- Pretty much. - Yeah.
But, luckily, we've got Slow Mo cameras
so we can slow it down.
So we're gonna try and write our names in det cord
and see if we can see it propagate throughout the whole thing
and spell our names out.
Brought out the big guns today.
We've got the V2511.
We'll start off at 28,000 frames a second.
Because I get the feeling 1,000 just won't cut it.
Okay, so I'm gonna talk to you about the det cord
in case you don't know what it is.
Essentially, you see this stuff here looks like an electrical cable?
It's actually just like a sheath with plastic explosives in the center,
which is what detonates.
It's not very sensitive.
So you can, you know, tear it, rip it, bend it,
crush it, stamp on it, set fire to it
and it won't explode. It won't detonate.
Which is why you need a detonator.
And that's gonna be electrically initiated with these cables.
Which then causes the det cord to detonate down.
So that's how it works, basically.
All right, how loud is this gonna be?
Super loud.
What?
- Exactly. - Yeah.
Three, two, one!
- Oh! - Oh!
Did you feel that shockwave there?
I heard it rolling over the hills.
It lifted all of the loose dirt around there.
It's completely disappeared.
That's mental.
And it happens in a blink of an eye, doesn't it?
Like you can't just like differentiate.
I didn't even see it. I had my eyes closed.
- Oh, did you? - Yeah.
I went like this.
All right, let's go see what that looked like.
All right.
- Woo-hoo. - I like that font.
Gav:
my name has ever looked.
Dan:
It's making it all look like it's all heat waves
going across the dust.
- Do you see that? - It's sort of hard to tell
but I think because the shockwaves are coming out
of each letter, it's blasting the explosion one way.
Then it gets hit by another one.
So the explosion is sort of going like vuu-vuu-vuu the letters.
Dan:
It explodes, then implodes, then explodes and implodes again.
Gav:
But also as the shockwaves go through the air,
that's also warping it.
So it looks really dreamy.
It's very much like water.
Dan:
Gav:
you get the same exact-- obviously, much, much slower.
It makes it look like it's underwater.
That could be on the seabed. You could trick someone.
That was fun, right?
Well, of course, it was fun.
So your letters were skinny letters
because you're skinny.
- Right. - Yeah.
I'm thinking fat letters because I'm fat.
So you're gonna bold your font.
Yeah. It's gonna be much bigger.
So the one we used was a 48 grain det cord.
For me, we're going 100 grain.
So it means that basically the letters are just gonna be fatter.
Is that physical thicker cord?
Or is it just densely, well...
Uh, I think it's actually physically like thicker.
Just got more plastic explosives in it.
Well, that's what you've been up to.
I have changed the frame rate on the V2511
from 28,000 frames a second to 90.
Oh, you've gone fatter than that as well.
Fatter frame rate, fatter letters, twice as loud?
I don't know about twice as loud.
But it's gonna be louder.
- All right. - You're gonna feel it more as well.
- All right. - Right.
Three, two, one!
It's just like... ( imitates explosion )
Yeah, yeah.
Did you hear that all the way over the back of the hills there for ages?
- That was mental. - Yeah.
- Cool, isn't it? - That's really cool.
Isn't blowing stuff up fun?
- It is. - Isn't it fun?
I can see why you joined the Army.
I love it.
This was shot much faster
so it's moving a lot slower through frame.
Oh, isn't that cool?
It actually looks very furry.
Looks like it's quite gonna be soft if you stroked it.
I wouldn't want to touch it.
No. Absolutely not.
That's the water ripple there.
That's just air molecules there all smashed up
- like, what is happening? - Yeah.
Det cord's pretty fast, isn't it?
- Rapid! - Really quick.
Rapid!
I wasn't messing around when I was saying
six kilometers a second, at least.
Sometimes up to seven and a half kilometers a second.
So we've set up this little finale area now.
Got a little trough of water.
Yeah. With this sort of puddle, the idea is that the det cord
moves so fast that it travels
through the puddle out the other side
and does some other stuff before the puddle even reacts.
Because the water should still only be like this high
by the time the det cord's finished going around
because it's so quick.
So it will be like cavitation under there?
Will this blow an opening in the water that's got no air in it?
Or whatever it is in the det cord?
It's just gonna be like an explosion underwater.
So it's just gonna send water up
- but much slower than the det cord moves. - Yeah.
Which will be a pretty cool effect.
- Let's do it. - All right.
Final big boom.
- Big bada boom. - Big bada boom.
You ready?
Yep.
Three, two, one!
Oh!
So good. Hang on.
That one lasted longer, I think.
Lifted that water up nicely.
It did. It really did.
Let's go look at the footage.
So, for comparison, we also filmed this on the Flex4K,
at 1,000 frames a second.
Different story altogether.
The whole thing's gone at once.
Dan:
Might as well just watched it with your own eyes.
Gav:
1,000 frames a second is still too fast.
Dan:
But it really shows you how fast it moves.
Gav:
Dan:
Gav:
Dan:
Gav:
Look at that.
That is like a split second work of art.
Like somebody framed our work.
Dan:
compared to det cord there.
Because it looks like an explosion with the water.
But the det cord's long gone, long gone.
And the water's still rising.
And it gets to about 30 feet.
Gav:
It's like a fountain in Vegas.
And the shallow water on the sides kicks up
way before the deeper water.
Oh, you see what's happened there.
The shockwave has hit the Lexan
that was protecting the camera.
and has bounced it front of the lens.
Or the camera blinked.
It was like, oh!
Does that happen?
Oh, yeah, yeah.
Phantoms have eyes.
Love a good shockwave.
Especially at 28,000 frames a second.
Hopefully, you also loved the shockwave.
Feel free to subscribe to the Slow Mo Guys.
And we'll see you right back here for the next episode of the "Super Slow Show."
I'm gonna get more det cord.
- Yeah? - Yeah.
- How much you got? - About 100 foot?
Ooh.
Hi, guys.
Click here to catch up on our latest adventures.
I barely survived, so I hope you like them.
Dan did complain a lot.
I do all the work!
Most of it.
You do 90%.
I do all the work.
All right, fine.