a Barong sword

[CharlesS]

Perhaps one of metals forging specialists could take the barong blade pics and explain what's going on in each of the differing shades of gray to near black. I think most of us would be interested in that type of analysis.

[Battara]

What kind of etchant did you use?

[Ian]

Roland:

That appears to be a very aggressive etch that you have used. Would you describe how you did the etching and what materials you used? Understanding more about your technique might help explain what you found.

Thanks.

Ian.

[Ian]

Roland:

It is not uncommon to see a marked etched pattern on barung. And I think Rick is correct when he says that the edge is actually an inserted piece of hardened steel between layers of softer steel/iron. I think Robert Cato, in his book Moro Swords, describes this method of pattern welding.

Here is one of my barung that shows an active pattern similar to your example, with what appear to be several different metals making up the layers of the blade.

Ian.

[DaveS]

Originally Posted by Ian

Roland:

That appears to be a very aggressive etch that you have used. Would you describe how you did the etching and what materials you used? Understanding more about your technique might help explain what you found.

Thanks.

Ian.

Phosphoric acid will bring out the pattern like this almost every time. It will accentuate the high and low carbon areas especially if the blade is slightly heated...........Dave.

[Roland_M]

Hello,

my etchant is very mild. The strong contrast comes from the scanner. The pattern can be easily removed within a few minutes with sandpaper 1500 or 2000. If i would use a strong etchant, this would destroy the micro details.

I use sodium persulfate (fine etch crystal) and a special technique, to bring out the finest details. It was a long way of experimenting. Compared to nital or nitric, sodium persulfate produce sharper details.

1: polish the surface up to a sandpaper grit of 3000.
2: etching with 20% Sodium persulfate (20Gramm (0.7 oz.)/ 100 mL distilled hot water) and a cotton ball until the result satisfy me
3: polish the surface again with sandpaper 5000 and 7000 or steel wool 000 + 0000 + Micro Mesh 8000
4: etching again with 7.5% Sodium persulfate (7.5 Gramm/ 100 mL distilled hot water (~50°C))
5: polish the surface with Micro Mesh 8000 and 12000 to a mirror finish (in this case).

The complete pattern is only visible under direct sunlight (the best way), halogen light or with the scanner.

Try it out, you will be surprised. A nice side effect, Sodium persulfate is a very effectice rust remover. The color contrast is not so good, FeCl is better, but after some bad experiences i will never ever again use FeCl on antique steel because it creates a kind of moon surface full of pitting under the microscope even when used with low concentrations (~5%).

Thanks for the pictures and comments. I also think, it is a three layers construction with hard steel in the middle, like japanese san mai.

Kind regards Roland