Detinting and passivation

[Atlas Knife Company]

Is there any reason to not use a product such as Elimitint by Prostar? Or, is it a case of passivation not needed in higher end 4xx series stainless and similar? Yes, I've used it and it is pretty quick and easy to remove the oxide layer by simply brushing on, rinsing, and wiping off.

 

[Stacy E. Apelt - Bladesmith]

Isn't it just an acid wash to remove surface oxides?

It will remove any easily dissolvable metal, like free iron, so it makes the surface have a more passive structure. In jewelry we call it pickling. I see no real use of it in knives, as we sand the surface down.

 

[Atlas Knife Company]

Yes, the detinting is a surface wash, but the passivation removes iron which creates a chromium oxide rich surface to enhance rust prevention. I wasn't sure if anyone had tried this as a protective coating on stainless knives, guard fittings, decorative pieces that are difficult to sand and polish.

 

[kuraki]

Yes, there are people passivating their stainless knives for increased corrosion resistance. I can't remember the specific maker I'm thinking of, but he was showing how he did it on Instagram. He was using nitric acid, though more concentrated than that solution is. That's what we use at work for passivating 304/316.

Anyone doing stainless san mai with carbon cores etching in FC is doing it too, whether they like it or not