Thread: Another Talon, kirinite old denim scales

My experience is that unhardened steel will etch just fine. I have etched unhardened damascus guard and buttcap material i the past with no problem. With that said, I have been told that it will actually etch more slowly than hardened steel, which is a bit counterintuitive.

Originally Posted by Bruno

The spine has to harden as well, or the core steel will not etch on the spine.
And the point as well, or it won't etch properly either.
And those places are where delamination is likely.

Very like the color and design of the handle.

Originally Posted by JDM61

My experience is that unhardened steel will etch just fine. I have etched unhardened damascus guard and buttcap material i the past with no problem. With that said, I have been told that it will actually etch more slowly than hardened steel, which is a bit counterintuitive.

Your experience is wrong.
Harden half a piece of steel and leave the other half soft.
Etch that.
See what happens.

It is normal that soft steel etches a lot less, since the carbon is distributed in a different manner, and the crystalline structure of the steel is different. Which in turn means the chemistry is different.

If parts are hard and parts are soft, it looks like crap.

Here is an example of where I did try to etch unhardened damascus. The blade was ovbviously hardened, but the guard and buttcap were not. In the case of the buttcap, it would not have made much difference as I had to heat it with a torch in order to silver braise a cut down Corby nut to the underside to mate with the threaded tang. That requires a temperature somewhere between 618C and 740C depending on the solver content of the solder. As a matter of fact, the buttcap were etched AFTER the knife had been put together and the buttcap was ground to shape and size. The reason that the pattern on the fittings is so bold is that it is "side" of a crushed W pattern billet. I don't have may ics of the buttcap and guard head on because they were lost when my old computer crashed.

Originally Posted by Bruno

Your experience is wrong.
Harden half a piece of steel and leave the other half soft.
Etch that.
See what happens.

It is normal that soft steel etches a lot less, since the carbon is distributed in a different manner, and the crystalline structure of the steel is different. Which in turn means the chemistry is different.

If parts are hard and parts are soft, it looks like crap.

bruno- by any chance are you saying that the hardened and unhardened portions would etch unevenly or to different contrast levels? not an issue of the steels not etching if not hardened but an issue of aesthetics because of uneven coloring/contrast? that is what ive seen on several pieces differentially hardened. forgive me if im misreading what you were saying

Originally Posted by silverloaf

bruno- by any chance are you saying that the hardened and unhardened portions would etch unevenly or to different contrast levels? not an issue of the steels not etching if not hardened but an issue of aesthetics because of uneven coloring/contrast? that is what ive seen on several pieces differentially hardened. forgive me if im misreading what you were saying

Yes, this is correct.
Hardened steel will etch much blacker than unhardened steel. Unhardened steel will at best turn dark grey (depending a bit on the alloys of course). No amount of etching can hide this fact, and it is very visible. Since hardening is critically dependent on termperature windows and time windows, it is perfectly possible to end up with a razor that has unhardened patches if you are not careful. Especially with steel like this, which has no alloys in the core steel to make it through hardening.

Additionally, the blackness on hardened steel doesn't come off easily, whereas the blackness on unhardened steel will rub off.

This is a matter of aesthetics. The hardness of the core steel in the spine is irrelevant for the functional aspect of the razor. It's just that blotchy etching looks ugly. If you look at the pics above, the core steel near the edge is etched a solid matte black. If you'd look on top of the razor, you'll see the same black for the core steel running through the spine. If the heat treatment would not be uniform, there would be grey blotches here and there. If you buy a razor like this, you buy it because you like the aesthetics. There is no functional benefit to damascus and suminagashi. It follows that in that case, there is a much lower tolerance for visual defects.