Unexpected Hamon

I'm starting to get the feeling I've messed up here.
I've just been hand sanding this razor I've made from an old file.
As I've got to 400 grit it looks as though I have a hamon showing up.
Its hard to see in the pics, but there seems to be a wavy pattern about 1/2 inch above the cutting edge.
I quenched it spine down, but I was outdoors in bad light, and now I'm wondering if maybe I didnt submerge the whole blade.
If i left the edge out of the oil for the first few seconds, would this leave it in a state too soft for a razor?
I just spent 20 minutes on my dtm 325 then king 1200 stone and the bevel still wasnt quite there yet.
So it seems pretty hard, but I'm tired and I want to go to bed now.
Am I kidding myself that this edge might still be useable
Thanks
Grant

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I may be wrong here but sanding with sand paper will not reveal a hamon, it never worked for me at least. You need to etch with acid, or polish with Jnats to get a hamon to show.

Thanks Stefan, I hope your right, and I'm worrying about nothing
G.

Nothing to do with the question. But I was talking to one of my files the other day.................:confused: and when it grows up it wants to be just like that.............
I have to thank you Grant, I now have a collection of old files that I'm keeping just in the hopes, that I may learn to do what your doing with these files, someday.

Hamons or temper lines happen on their own with razors a lot of the time. The thin material down by the edge cools faster than the more meaty cross sections up by the spine. You can see the temper line during the sanding process. If you want to emphasize the line you can etch the razor in weak acid, if you want to make it go away buffing does a good job of obscuring the line.

Charlie

Quote:

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Originally Posted by baldy

I'm starting to get the feeling I've messed up here.
I've just been hand sanding this razor I've made from an old file.
As I've got to 400 grit it looks as though I have a hamon showing up.
Its hard to see in the pics, but there seems to be a wavy pattern about 1/2 inch above the cutting edge.
I quenched it spine down, but I was outdoors in bad light, and now I'm wondering if maybe I didnt submerge the whole blade.
If i left the edge out of the oil for the first few seconds, would this leave it in a state too soft for a razor?
I just spent 20 minutes on my dtm 325 then king 1200 stone and the bevel still wasnt quite there yet.
So it seems pretty hard, but I'm tired and I want to go to bed now.
Am I kidding myself that this edge might still be useable
Thanks
Grant

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Attachment 131028

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Grant, now I've not yet made my first razor so this is all hypothetical but did you test the edge before tempering? Supposedly it should make a file skate when it's sufficiently hardened. I'd guess if it did then you are OK.

I just read the first post again. If this were my razor and it was for personal use, I would hone it and see how it works. I bet the blade will work fine.

Charlie

Looks cool!
... but, what will that back do to your strops?

Thanks guys, I'll hone it when I get home from work tonight.
Hopefully I'm just being paranoid. As soon as I finish a heat treat I start to second guess myself & think I've done something wrong.
It does still skate a file. Although after I set the bevel last night then tested on the file it did chip it up a bit but thats probably normal?
G.

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Originally Posted by mainaman

I may be wrong here but sanding with sand paper will not reveal a hamon.

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Yes, it will.
And if you used a polishing stone, it would as well. It won't jump out at you, but it will definitely show itself clear as day when held to the light.

Btw, why would you quench spine down?
The edge is the business end. That's the most important bit, so it should go in first.

I've heard it recommended a few times, Bob Allman is one who does it that way

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Originally Posted by Bruno

Yes, it will.
And if you used a polishing stone, it would as well. It won't jump out at you, but it will definitely show itself clear as day when held to the light.

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+1 .. The Iwasaki I restored was showing quite early & on reaching 2000 wetndri was very prominent.

Grant, are you planning on making it feature of the blade ?

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Originally Posted by onimaru55

+1 .. The Iwasaki I restored was showing quite early & on reaching 2000 wetndri was very prominent.

Grant, are you planning on making it feature of the blade ?

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There are not that many options otherwise :)
It's a feature of the crystalline structure of the steel.
Even if you polish it to a mirror shine on the buffer, you'll still be able to see it. If not immediately, then eventually as the patina develops differently.

Well I dont think I have anything to worry about.
My main concern was that if I had a hamon line, and I quenched spine down, that I didnt fully submerge the blade in the initial quench.
In my mind the result of that would be the edge not being as hard as it should be.
However I've just taken it to the hones.
The DTM 325 started setting the bevel OK but was leaving it very chippy.
The King 1200 was getting me pretty much nowhere though.
So if anything its too hard, which is good. Because I can just put it back in the oven a little hotter than the last temper cycle.
If anyone see's any holes in my ameture logic please let me know.

So I still cant explain the Hamon other than what Charlie said earlier, really I cant even be sure thats what it is until i polish further, but to answer Oz's question. If all goes well yes I'll probably etch the blade to bring it out.
Hopefully have a good looking and functional razor
Thanks
Grant

Quote:

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Originally Posted by Bruno

There are not that many options otherwise :)
It's a feature of the crystalline structure of the steel.
Even if you polish it to a mirror shine on the buffer, you'll still be able to see it. If not immediately, then eventually as the patina develops differently.

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Yes, not many options. It was almost a rhetorical question. ;)
Not sure but I think Iwasaki western razors were just finished western style ? I may be wrong but I never saw one with a trad. polished hamon till I got to work on a couple.

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Originally Posted by onimaru55

Yes, not many options. It was almost a rhetorical question. ;)
Not sure but I think Iwasaki western razors were just finished western style ? I may be wrong but I never saw one with a trad. polished hamon till I got to work on a couple.

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I have seen a lot of the western Tamahagane ones, on pics in NOS condition plus the two I have, they all were mirror finished and there was no visible hamon.

An interesting thread that is related to this one.

http://straightrazorpalace.com/works...tml#post857646

Charlie

The reason is as Charlie stated, and in the hamon thread. Old files are very likely low hardenability, very clean steels. That difference of 0.25 inch at the spine is enough to slow the transition during hardening to have a hard martensitic edge and a softer pearlitic spine. Hardening is a process that happens at the speed of sound in the steel. Just a little fatter area behind the edge is enough to make the difference in the structure, within the time allowed, or the addition of a little more manganese as in 1084 and you have a through hardened blade. Fascinating material eh?

That is going to make a fine looking razor....!

I wouldn't be supriced if it was the jnats that made the Japanese make their good blades.
As they could see what happened when hardening and then they started to play with different steels and techniques.

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Originally Posted by Bruno

Btw, why would you quench spine down?
The edge is the business end. That's the most important bit, so it should go in first.

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I am not sure that it matters, but, spine down or up should result in nearly the
same hardness result on the thin blade. Hardness is not the only issue.
As the parts of the razor are quenched they change dimensions diferentially
and on a big sword will curve. The edge should be in slight tension.... without
tension it might potato chip warp. Too much and it will crack... If the blade looks
correct and not warped then you did it correct (simple answer).

As for hamon without a clay line... The back of the razor has steel much thicker
than the cutting edge. Heat will stay in the thicker steel for a while then migrate
from the thicker spine toward the thinner edge after it comes out of the quench.
Depending on the grind and quench timing the heat might move out enough to be seen
after polishing and etching. The differential might vanish with later annealing.

If the file pattern is still sharp enough to worry hones a single layer of tape should solve that.
It looks like the tops are flat enough though. Clay, molten lead, molten salts, oils, argon are used by
some to keep the carbon from burning off... The magic of modern hones will prove of value if the steel is very hard.

Beautiful work. If the heat treatment is right it should hone shave very well.
Enjoy...

Not sure I agree. If you quench spine down, the edge will touch boiling water / steam when going down, because the water (or oil) has been pre-heated by the spine. Especially if you hesitate when going in. That could lead to uneven hardening. This is a risk, not a certainty. I've done a bit of experimenting with hardening lines on kitchen knives, and I've seen this happen sometimes, when my quenching motion was hesitant.

Here's a couple of better pics after re-tempering last night.
Hopefully you can see the Hamon I'm talking about
This was sanded to 320 grit before going into the oven.
It's still pretty hard actually. I might end up putting it back in for another hour at 420 F if I'm still struggling to get a bevel set.

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Grant

Nice colors. Looks like the hardening line drops off by the heel. It will be worth observing if there is a detectable resistance chance on the hones there. Hamon are funny things, they can go places you don't want just as easily as not going places you did want.

Wish I lived close to you Grant, I've got the stones to work on it...we are just a few miles away from one another. That blade is a great looking blade and yes, I can see the hamon well. This just ads to the character and beauty of it. You have a good eye my friend and I always enjoy looking at your ventures.

A suggestion maybe, there is something that has been added to the file steel when it was made. Being that file metal is a pretty good material from the manufacturer would there possibly be an ingredient that was added at the time of manufacturing that is unique to that manufacturer. Like grandmas cheese cake recipe. It was great but nobody could duplicate it. But that material is showing up because of the way the quenching is done. Like spine down is cooling faster and driving that material up to the finished end. Just a thought. In 30+ years of machining and welding I have seen metal changes in color and looks that nobody had an answer for. Go figure. Good luck grant.

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Originally Posted by walleyeman

A suggestion maybe, there is something that has been added to the file steel when it was made. Being that file metal is a pretty good material from the manufacturer would there possibly be an ingredient that was added at the time of manufacturing that is unique to that manufacturer. Like grandmas cheese cake recipe. It was great but nobody could duplicate it. But that material is showing up because of the way the quenching is done. Like spine down is cooling faster and driving that material up to the finished end. Just a thought. In 30+ years of machining and welding I have seen metal changes in color and looks that nobody had an answer for. Go figure. Good luck grant.

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Walleyeman may be onto something. A file needs to be hard as heck yet not fragile. I would not
exclude tricks putting harder steel on the surfaces and also case hardening.. In this case my bet is
on heat in the thicker spine not reheating thinner steel of the blade area. This differential quenching
trick is interesting. Way back I was taught that hammers were sometimes quenched by a gentle stream
of quenching oil in the center of the face. The rest of the hammer face was cooled a lot slower so it
would not chip.

In the end it is the shave test that tells all. The rest can be a secret....

Old files, from reputable brand names, are more likely to be good steel all the way through.

Since the 1980's there have been reports of files being case-hardened mild steel because manufacturing costs are lower and no one is in the business of resharpening used files to any great degree. They have become consumable items, used and scrapped.

The problem with heat treating a case hardened file is that the skin of hardenable material is very thin (thousandths thin) and that carbon added to the surface of a file will dissolve into solution at the hardening temperature and average itself throughout the bar. In the case of someone who is doing forging, this takes only three to four heats. While the carbon content might be 1.00% at the thousandths thick stage, it will be significantly less so when averaged against the mass of the file itself.

Someone who grinds a razor from a case hardened file, will remove the case hardened layer by the time they get to a razor shape and it won't harden anyway. There would be no hamon at all unless the parent steel was sufficient in enough carbon to harden on its own.

It is technically possible to add or subtract carbon from a steel bar by placement in the column of fire in the forge. I would not eliminate this as an accidental or intentional possibility but Baldy will have to share his forging methods. If he's of the school of "stick it in the fire, get it hot and hammer," then it could be accidental but the odds are that he will burn out more than he adds to the steel. Intentional addition of carbon from a coal or charcoal fire implies a better than average intent (experience).

QED: this file is hardenable and no special tricks were done to make it so. And, yes, weird things happen with steel, which makes it so much fun to play with.