Not a knife test but interesting penetration test of different blade styles

[Cobalt]

I had some heavy 3/4 inch plywood left over and decided to hit it with 3 different blades. The plywood is very tough to go through so these were very interesting results.

The 10 inch long, 0.2 inch thick blade penetrated exactly 3 inches into the plywood with a single hit and I repeated this several times.

The machete penetrated the same every time. The thickness of the blade at the middle which is about 2 inches, but it was hell removing it from the plywood.

The khukuri penetrated less than 1.5 inches into the wood. All were convexed edged by me.

I repeated these hits a bunch of times with the same results.

here are the pics:

10 inch blade length

Khuk and machete

 

[sodak]

How about edge damage? I've tried 3/4 inch plywood in years past, and it chewed up a lot of my edges.

 

[Cobalt]

Edge on the blade was fine, and it is a 440A blade. Edge on the machete was rolled, but not bad and the khkuri edge was a little rolled or minor micro fractures, but nothing that can't be sharpened out. All three have convexed edges so I think this helps. I did a lot more hits with the knife and it took it all with no problem.

 

[sodak]

That's good. I have a large heavy bowie in 5160 that I thinned out, and I took some pretty gruesome chips out of the edge. I didn't think I thinned it out that much, but evidently, I did. I'll try convexing it next, 3/4 plywood is some pretty tough stuff!!!

 

[Cobalt]

I have noticed chipping in 5160 even with this khukuri which is 5160. I think 5160 has lots of flex strength, but when it comes to fracture toughness it isn't as good as people think it should be. I have put some serious chips in khuks before. I have actually had better luck with 10xx steels. But 440A and 420 steels have always been fairly tough. I did put some serious dents in that knife pictured above when I batoned it through a bunch of large 4 inch nails. Was using the knife to remove some wood framing in my basement and used it as a chisel with a hammer. It is a very tough knife. And easy to sharpen. It is the old George Lainhart spec ops machete made for Colt by united cutlery.