View Full Version : Question on reactivity

02-21-2013, 01:04 AM
So I just bought a Kobayashi Seikon Dojo nakiri, Blue #2 core clad in low carbon steel. My only other carbon knife is a Hiromoto AS petty that I forced a patina on right away. I tried forcing a patina on the Kobayashi using mustard, raw beef, and lemon juice, and it really hasn't done anything. The mustard just left some slight markings. Is Blue #2 less reactive than most carbons? Even less than AS apparently, which is in the same family. The low carbon cladding has been fine too. Found it interesting and thought I'd share.

02-21-2013, 01:21 AM
It is possible that there is a protective coating that needs to be cleaned/scrubbed off first.

02-21-2013, 01:55 AM
where are you trying to force a patina on? just the edge itself or the whole blade?

02-21-2013, 02:11 AM
The whole blade.

02-21-2013, 02:19 AM
uhm both blades are clad in stainless so the only part that'll have a patina is the edge, and that patina goes away whenever you sharpen it.

02-21-2013, 02:30 AM
Yes only the 1/4" or so of exposed core on the Hiromoto AS is carbon, and that is the only part that is patina'd. But the description of the Kobayashi sounds to me like the cladding is not stainless. So I tried to patina the whole blade. Regardless, the core steel is very exposed on it, at least a 1/2". It was the only part of the blade that showed any staining at all from the mustard, even than it was just a couple marks, nothing like the Hiro AS which stained/patina'd quite obviously. I think the cladding might be painted though, I've never seen a steel so evenly flat grey color before. But I'm no knife expert either.

02-21-2013, 02:58 AM
I say with with no expertise in metallurgy, but my observation is blue does not react as quickly as some others, but produces a darker patina as opposed to the greys I get with white.

02-21-2013, 03:05 AM
I wouldn't even worry about forcing it. It doesn't seem like the steel is terribly reactive anyway.

02-21-2013, 03:07 AM
on the blue steel that i have, i only get a dark grey patina that forms on the exposed edge of my knife. mine is clad in soft stainless as well.

02-21-2013, 04:36 AM
Sounds like others' experience is the same as mine then...I may recommend this steel to friends who would normally want stainless only.