Acid etch comes off?

[Forgedog]

I posted a while back about my attempts at ferrich chloride etch.
It looked ok... But I tabled it for now because idk how to describe it.
The greyish black coating from the acid has a powdery feel and it rubs off with a towel...
I know that some of it is supposed to rub off... But "so much"? Seems like 99% of it comes off...
Ive read toure supposed to buff it with super fine steel wool... Havent tried that yet but from the little experience ive had it sems like it would all be buffed off in a matter of seconds.

 

[Chris Railey]

To answer that the guys here will need to know what kind of steel you used and what ratio of dilution you used for your FC.

 

[KenH]

When the etch is fresh the oxide will rub off so easy as you say. Let it sit a day or so and it's just a tad tougher. I've read you can also boil in water for 30 minutes to make it last better. I'd sure LOVE to find something that would make the beautiful black oxide on San Mai edge last.