Damascus striations?

[Paul Sherman]

Working on a blade of 1084 and 15N20 Damascus. Blade has been heat treated, sanded up to 800 grit then given several dunks in ferric chloride to desired depth.
However…what are these lines? What’s weird is that they are so straight and they are on the “low” part of the etch. Before etching this blade was shiny, smooth with no trace of pattern evident, then they appear.
Any idea what causes this?

https://photos.app.goo.gl/UbRB7Zww2ZVeuXpC6

 

[weo]

Did you wipe off the blade after the etch? That's what it looks like to me. The black oxides from etching can be easily wiped off right out of the etch. What I do is etch, neutralize in baking soda and water, then let air dry overnight before cleaning off the 15N20 with 5000 grit paper tight to a sanding stick after a day or so.

 

[Paul Sherman]

Did you wipe off the blade after the etch? That's what it looks like to me. The black oxides from etching can be easily wiped off right out of the etch. What I do is etch, neutralize in baking soda and water, then let air dry overnight before cleaning off the 15N20 with 5000 grit paper tight to a sanding stick after a day or so.

Very good, that makes sense. I’ll try not touching it after the etch.

 

[Paul Sherman]

Did you wipe off the blade after the etch? That's what it looks like to me. The black oxides from etching can be easily wiped off right out of the etch. What I do is etch, neutralize in baking soda and water, then let air dry overnight before cleaning off the 15N20 with 5000 grit paper tight to a sanding stick after a day or so.

Weo, do you do multiple dips in the FC and scrub off the oxide in between?

 

[weo]

Weo, do you do multiple dips in the FC and scrub off the oxide in between?

Yes, and I vary the time depending on the outside temperature, in the summer 5-10 minute etches, and in the winter, usually 15 minutes works well.