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This Kiritsuke is made of k720 aka O2 Steel differentially hardened and tempered to edge hardness between 60 and 65 Rockwell. Overall lenght is 280mm with 160mm long blade 51mm at the widest and tapered 3mm thickness. Handle scales are made of stabilized olive wood, wengè and doussie with cork and black felt liners. Pins are carbon fiber, brass and brass tubing filled with white resin (that looks black) of 3 and 4mm in diameters. This is not a traditional kiritsuke, it is my interpretation with western style full tang handle construction and bevels ground on both sides. Still a multipurpose chef’s knife like the classic kiritsuke. Looks like I can’t get an hamon line on this k720 steel, this process failed already a couple times for this steel but works very well for other like 1070 (c70). It might have to do with the rather long soak time required (between 15 and 20min at 820°c). Thankfully the acid etch in ferric chloride revelad a cool steel structure that I quite like and almost looks like a very high count damascus. Still a great steel I think! It took me a while to decide the handle construction this time, this is why I drilled pin holes on tang later on after the heat treatment. I do not suggest this at all, k720 steel is somewhat hard even if not quenched, drilling took a long time and a broken bit. I also experimented with punge line, ground it off on near the edge to have the entire lenght sharp but also a flat spot between handle and blade for a straight scale glueup. First time for me, I’m sure it has been done before but I have never seen it myself. I like the effect of the plunge line a lot this way, will do it again!
