Does ferric chloride "go bad"?

[jfindon]

Awhile ago I acid washed one of my blades, and the acid sat in a mason jar for over a year before I tried to do another blade. This one wasn't affected by the acid at all, does it ever "go bad" or does M390 just not react with it as much?

 

[J. Doyle]

It shouldn't go bad at all in that sense. If you were doing lots of etching constantly it could not etch well anymore.

But here isn't that case. Ferric chloride works mainly on carbon steel, not stainless. I would think it would have almost no effect on m390.

 

[jfindon]

It shouldn't go bad at all in that sense. If you were doing lots of etching constantly it could not etch well anymore.

But here isn't that case. Ferric chloride works mainly on carbon steel, not stainless. I would think it would have almost no effect on m390.

See I'm terrible with which steels are stainless and which aren't and apparently too dumb to Google that. Thanks