How Many Walls Stops A Lego Cannon?

Shooting balls of different weights into Lego castle walls. The same Lego rubber band cannon is used for all shots. Enjoy!

Making of the Lego cannon:

Slow mo camera:
Sony RX100 V (can record at 1000 fps)

[azekilldiablo]

Those U walls and supported walls models are a brilliant way to show how force transfers over a wall... in the slow motion, we can see that the pieces that took the biggest hits are actually the ones at the back, it's fascinating!

[plazmadolphin]

These tests were done on a baseplate allowed to move freely against the floor. This made it so a significant amount of force was absorbed by the baseplate tilting, which is unrealistic in lego war situations. It is very likely that the cannon would have more penetration power if the baseplate were bolted down (or otherwise fastened) to the floor.

[irchonite]

I love this because, although this is still a recorded experiment, I think it's the closest I've seen to you just playing with legos. Like, simply setting up lego walls and attacking them with lego weapons? That sounds like something so many of us did as kids and I'd be lying to say it doesn't still sound fun!

[joshwa]

I just watched a guy shoot marbles at plastic for 4 minutes and I enjoyed every second

[GibbyTheDude]

If this dude was my science teacher, I would love science.

[zkelethor]

1:52 I really like how the initial blow of the ball didn't break the walls, but the recoil from the baseplate resetting back to its flat position flung the walls off of the baseplate haha

[SuperTimLand]

There was no unnecessary attempt to get 10 minutes, no long intro about subscribing, no filler, no click bait, no voice at all. You delivered exactly what you said in a very entertaining way.

[arfansthename]

I love how the comment section is just a meeting of different engineers, this channel is really going well, I'm proud of it

[liamdaughton]

Seeing the reflection of the camera in the metal balls was nice

[michaelplautz]

I’m so glad the findings were included at the end. I really wanted to see them all compared.

[Splitfinger]

Brave knight: so what kind of tests are these going to be?

Oh, just some structural tests. You should survive most of the time.

Brave knight: ... should survive?

[totoshampoin]

Suggestion:
- Add weight to the ground, so the energy is not lost in it
- Double/Triple check when a marble fails, to see if it fully fails, before going on to a stronger one

[pumpkingamebox]

I find it mighty interesting that it’s more efficient to use single walls rather than any other against tungsten.

[mmmemebigboy]

Loved that this video just started. No excessive talking/ explanations, just went into what we came to see

[RedSarGaming]

As an engineering major, watching these videos gets me more excited for engineering than my actual design classes lol. LOVE THESE!!

[zachlewis]

I think we should get a part 2 with this video. I want to see how you would defend against repeated strikes, let’s say 3-5 shots. Walls aren’t build to take one hit and crumble and say they worked, walls are meant to stand the test of time and battle.

Also the base plate thing everyone else mentioned.

[Athenor]

That is awesome, seeing how the energy dissipates. Would you be willing to do a series where the base plate is strapped down or secured, such that the walls can't transfer energy to it?

[willowthe_birdwatcher]

Next up: How to build a particle accelerator out of LEGO

[krayghan]

Man I love these things here because they are such good demonstrations of just regular concepts in both physics and engineering lol

[TheAdvertisement]

0:16 The way the marble just took them all out so cleanly caught me off guard. xD