Kickstarting a tough, flexible first responder axe carved from AR400 armor plate


#1

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#2

No bottle opener?


#3

I want one just to carry around.


#4

It’s carved?


#5

We had an explicitly designed-in one and then took it out because of potential concerns from fire departments.

However I’d be quite surprised if you couldn’t find other parts of the axe that will open bottles quite handily :grinning:.


#6

Yes, it’s carved out of AR400 steel with a jet of water and garnet traveling at Mach 3.


#7

Aww, I liked this comment, then you deleted it. :frowning:


#8

Another way of looking at it is water pushing the metal out of the way.


#9

I screwed up! Bad UI! Or bad poster!

Let’s try it again;

We had an explicitly designed-in one and then took it out because of potential concerns from fire departments.

However I’d be quite surprised if you couldn’t find other parts of the axe that will open bottles quite handily :grinning:.


#10

sometimes the little (microscopic) chunks of steel that are knocked off the plate ricochet up and out rather than going straight down into the tank. When they hit free air they are going up to 3 tines the speed of sound snd so they vaporize into tiny little meteors that seem to just appear in the air.

It’s mesmerizing.


#11

Holy moly! Tell the truth - is that just to be cool, or does it work better? (And I thought “carved” was just another ahem creative headline.)


#12

One of only ways to cut AR400 is via waterjet - it’ll eat normal tooling for breakfast. It’s toughness is why we chose it - those hits on concrete did absolutely no damage to the blade.

So yeah, it’s better. :grinning:


#13

A flexible axe? That sounds… bad?


#14

Kind of like a flexible plane wing, or a flexible car frame, or a flexible suspension bridge.


#15

I still don’t quite get it. The purpose of those other flexible structures isn’t to deliver a forceful impact upon a target.

With a flexible axe, wouldn’t you be dissipating some of the axe’s energy into that bending, rather than turning it into a useful impact force?


#16

That is totally awesome. You should make a video of making one of these things.


#17

I would assume the flex is side to side, due to the thinness of the metal plate, and that there is very little fore and aft flex in the direction you’re applying force in.


#18

Ah. THAT makes a bit more sense.


#19

What Space Monkey said. It’s a solid .25 inch by 1.25 inch AR400 steel plate. It’s not flexible in the geometries that need to be rigid.

Good swords are super flexible too.


#20

We have some time-lapse waterjet videos and will be posting them later. We don’t have an in-depth end-to-end one (which I happen to find fascinating!) but we will do one if people are interested (and we get funded).