Etching with iron(III)chloride hexahydrate

[blue lander]

How polished should a blade be before you etch it? Does it need a mirror finish?

If you etch a blade that's been cleaned and not polished and no pattern emerges (steel just turns uniformly gray) is it possible that you'd get a pattern if you put a mirror finish on the steel and tried again? Or would you at least see some evidence even without the polishing?

[kai]

How polished should a blade be before you etch it? Does it need a mirror finish?

No polish needed per se - it's a matter of taste or what the traditional approach would be for a given culture/piece.

If you etch a blade that's been cleaned and not polished and no pattern emerges (steel just turns uniformly gray) is it possible that you'd get a pattern if you put a mirror finish on the steel and tried again?

Quite rare but possible: If a blade has been polished with power tools the laminations at the surface may be obscured. If accumulating surface rust has not eaten through this "smear" layer the laminations may still not visible. Repeated etching and polishing (by hand) may help to expose any laminations though.

Regards,
Kai

[Jens Nordlunde]

As it has been mentioned, FeCl3 is very agressive, so you have to be careful.
Some time ago this was discussed, and some suggested anything from pineapple juce to lime juice.
I find that ferrycloride is very good, but maybe you should try it on a blade of less value, so you know what happens, as you can always remove it, but just to make sure you know how it works.
Make sure you have the neutralisers at hand before you start.
You may end up with a blade slightly yellowish, but this can be removed by adding acid free oil and work the blade over with very fine steel wool - very gently.
Good luck
Jens