Hatsukokoro Kaijin Aogami #2 180MM Bunka

**About Hatsukokoro Kaijin**  

Hatsukokoro Kaijin (海神) –  God of Sea

The Hatsukokoro Kaijin (海神, Sea God) is a relatively new addition to the Hatsukokoro lineup. It is a straightforward, no-frills series that places performance above aesthetics. Featuring a clean Migaki (polished) finish, a sandblasted bevel and no unnecessary decorative elements, its appearance is understated. However, don't let its simplicity fool you. If cutting performance is your priority, the Kaijin offers tremendous value for its price.

At its core is Blue No.2 (Aogami #2) carbon steel from Hitachi, known for its ability to take an exceptionally sharp, aggressive edge with excellent feedback on the cutting board. Paired with stainless steel cladding, it offers the cutting characteristics of carbon steel while keeping maintenance relatively manageable. It is a practical choice for those who want to experience carbon steel without committing to a fully reactive blade.

One of the key factors behind a good-performing knife is not simply how sharp the edge is, but how well the overall blade geometry works. A good knife needs an edge that bites aggressively into food, combined with a bevel that allows the blade to penetrate and release food smoothly. This is where the Kaijin performs particularly well.

The blade is ground exceptionally thin behind the edge, gradually transitioning into a subtle convex geometry. This combination allows the knife to glide through ingredients with minimal resistance while helping to reduce food sticking. Although very thin slices may occasionally cling to the flatter section of the blade, its overall cutting performance is impressive. In our potato tests, it outperformed most of the knives we have tried, with the exception of a few featuring more complex, hand-ground bevel geometries.

Another advantage of Blue No.2 is its ability to achieve high hardness while retaining a good balance of toughness. This allows the maker to work with a thinner blade geometry without compromising performance. The result is an edge that delivers an aggressive bite, particularly noticeable when cutting through proteins and ingredients with tougher skins — an experience that conventional stainless steel knives can sometimes struggle to replicate.

The Kaijin is also exceptionally thin, making it particularly appealing to those who appreciate laser-style knives. It is completed with a polished Migaki finish and a Wa-style octagonal mono-ebony handle, which complements the overall understated appearance beautifully.

Who would I recommend it to?

I would recommend the Hatsukokoro Kaijin to anyone who has been using entry-level stainless steel knives, such as VG10, and is looking to explore carbon steel. It offers a noticeable step up in cutting feel and performance, without demanding the maintenance or investment of some higher-end carbon steel knives.

For what it delivers at its price point, it is genuinely hard to beat.

• Origin (Made in): Seki, Japan
• Brand: Hatsukokoro
• Knife Type: Bunka
  
• Blade
  • Construction: Sanmai
  • Grind: Double-edged Blade (50/50 Grind
  • Hagane (Core Steel): Aogami #2 (Blue #2)
  • Jigane (Cladding): Stainless steel
    
  • Hardness: 63-64 HRC
    
• Blade Finishes:
  
  • Migaki
  • Sand-blasted
• Blade Length : 180mm
• Blade Height (at heel): 48mm 
• Spine Thickness
  • Above heel: 2.5mm 
  • Middle: 1.2mm 
    
• Handle
  
  • Full Bulbinga Wood
    
• Weight: 140g 
  

**Care Instructions:**  

Aogami #2 (Blue #2) is a premium high-carbon Japanese steel renowned for its sharpness and edge retention. However, it is not stainless, so the blade must be thoroughly dried after each use—especially the exposed core steel beyond the stainless cladding. Over time, a natural patina will form along the cutting edge, appearing as slight discoloration. This is a normal characteristic of carbon steel, not a flaw, and can even help protect the blade from rust.  

The iron cladding, which covers much of the blade, reduces maintenance and it will still rust. So make sure to wipe it dry after use and apply a layer of oil ( our kurobara oil or any neutral oil ) at the end of the day before storing it. To maintain the blade’s edge and its lifespan, avoid chopping it on bones and frozen foods.