Fun with shallow-hardening carbon steel

fretworn

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TGF Recording Artist
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The steel in the photo above is W-2

This one is made out of 1095 … When good blades go bad (“tink”) … a tough water quench.

Great pattern tho - lol (differential heat treat)


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Man, I would love to learn to work with metal and am actually going for a blacksmithing course…..actually, I might have missed it already. I keep buying a ticket to it and forgetting about it or something like covid pops up and cancels it. I think the current ticket I have is for a course on making an axe, which seemed a lot cooler than making a hammer.

I have a huge appreciation for Japanese swords, too. Probably the 2nd-most watched thing on my YouTube next to guitar videos is sword making. It’s AWESOME how these dudes hundreds of years ago could figure out metal purities and how to work with them without any kind of scientific tools to do so. I suppose it was “Well, Bob tried to stab the guy but your sh*tty sword broke and he lost his head, so can ya figure out how to make it stronger?” :rofl
 
Man, I would love to learn to work with metal and am actually going for a blacksmithing course…..actually, I might have missed it already. I keep buying a ticket to it and forgetting about it or something like covid pops up and cancels it. I think the current ticket I have is for a course on making an axe, which seemed a lot cooler than making a hammer.

I have a huge appreciation for Japanese swords, too. Probably the 2nd-most watched thing on my YouTube next to guitar videos is sword making. It’s AWESOME how these dudes hundreds of years ago could figure out metal purities and how to work with them without any kind of scientific tools to do so. I suppose it was “Well, Bob tried to stab the guy but your sh*tty sword broke and he lost his head, so can ya figure out how to make it stronger?” :rofl
Actually there’s a ton of truth to your last sentence! 🎯

Differential heat treatment was developed by the Japanese in order to provide a hard edge, but a soft spine.

It turns out the tomahagane - Japanese sword steel is really kinda spotty carbon steel, hence all the folding/homogenous carbon distribution.

They either made a sword that was too hard and brittle and broke on the field… Or is it bent anytime you hit something. Differential heat treatment solved that problem for them.

In the movie the last samurai, you see where they ban the wearing of swords. These weapons went on the walls as objects d’ art.

I put hamons on knives because they’re beautiful and hard to do right.

The apprenticeship for a Japanese sword polisher is 10 years, alone. We don’t have that kind of patience in the west.
 
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Man, I would love to learn to work with metal and am actually going for a blacksmithing course…..actually, I might have missed it already. I keep buying a ticket to it and forgetting about it or something like covid pops up and cancels it. I think the current ticket I have is for a course on making an axe, which seemed a lot cooler than making a hammer.

I have a huge appreciation for Japanese swords, too. Probably the 2nd-most watched thing on my YouTube next to guitar videos is sword making. It’s AWESOME how these dudes hundreds of years ago could figure out metal purities and how to work with them without any kind of scientific tools to do so. I suppose it was “Well, Bob tried to stab the guy but your sh*tty sword broke and he lost his head, so can ya figure out how to make it stronger?” :rofl
Take the class brother - best thing in life is learning.

I don’t forge, but use flat stock and grind. Heat treat, quench and temper.

Then build the handle and finish all.

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Small stainless kitchen sword for youngest son. 9.5” chefs knife. Cryo treated.
 
I heat treated an M2 punch Monday. Wrap in foil, throw in oven and heat to 2200. Remove from oven and rapidish air quench, then bring it up to 1050 for 3 hours and let come to room temp slowly. Totally different than what you are doing, and not as fun
 
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Another failure mode. The hamon (the whitish line that differeiates between the hard edge (martinsite; the hard steel crystalline structure)) and the relatively softer spine.

This goes through and through the entire blade… Meaning it is not just a surface phenomena.

With enough polishing, this will eventually pop. But the problem here is that the line touches the edge; so there is soft metal on the edge. So many variables. :clint

No bueno. Rinse, repeat.
Anneal, re-clay, HT, quench
 
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O1 tool steel w Cambodian Rosewood scales. Unfortunately the scales are brittle and cracked, so I could not sell. Became my own personal shop knife.

O1 (oil quench tool steel 1) is not shallow hardening due to the chromium in the high carbon steel. But tough as hell. Not D2 tough, but good enough.
 
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An example “clay” pattern. Both sides.
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The notion being that the area covered in clay will cool more slowly and thus, less quench = less hard.

You can play with the patterning to draw all kinds of things.

One famous pattern is a chrysanthemum flower. Of course the Japanese have about a dozen or so “schools/eras” of design patterns.

And every different mark in the pattern has a name.
 
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Messed up photo; reflecting my hand. Oops 😬
But awkwardly demos how highly polished these hamon blades get.

Regular custom knives only get polished to about 800 grit at the most. I like a satin finish on knives. But to pop a hamon is a real craft. Takes weeks of hand work; super specialized process of etch and polish.

I love that knife actually. I have it around here somewhere to demonstrate to people how beautiful this really can be. It’s made out of W-2 steel which makes some of the best hamons imo.
 
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2x72 belt grinder w a freakin’ surface grinder attachment… lawd oh lawd …

Show Me The Money GIF



Ordered. There goes the tele until next spring.
 
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Oddly big “survival” knife. I did not make this one, however it’s in my go rig. 1/4” thick and coved in some black schmoo coating. Wildly sharp.
 
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