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Home | Japanese Kitchen Knives | Myojin Riki Seisakusho 180mm Bunka Cobalt Special Stainless Bubinga Ha

Myojin Riki Seisakusho 180mm Bunka Cobalt Special Stainless Bubinga Handle

$301.00
$301.00
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READ IMPORTANT DELIVERY OPTION INFORMATION

Hand ground stainless clad Takefu Special Cobalt stainless fine convex ground by Myojin Naohito at his workshop Myojin Riki Sesakusho in Tosa on Shikoku island.

Cobalt Special is a high performance stainless steel from Takefu Specialty Steels made specifically for cutlery. It’s alloy and refining techniques provide excellent rust resistance, edge life toughness and edge formation. Cobalt Special has 1.1% carbon, 16% chromium along with tungsten, molybdenum and vanadium and cobalt which strengthens the matrix and adds to edge holding.

It must be noted these are ground very fine and will not tolerate rough use, no bones or twisting on cutting boards. 

Naohito-san became known to us here from his fabulous grinds and finishes on the Konosuke Fujiyama FM knives. We have been consistently impressed with how nicely these fine blades cut and at the quality of his finish work. It is exciting to get more knives finished by this young but very talented sharpener and now blacksmith as Naohito-san has begun to forge some of his own knives. 



About This Knife

General Purpose

Good for veggies and boneless protein

Avoid Bones & Dense Foods

If you can't bite it, don't cut it.

Stainless Steel

Non-reactive blade.

Convex Grind

Super smooth cutting feel.

Ambidextrous

Suitable for all users.

Bunka

A bunka is a Japanese multipurpose kitchen knife known for its angular kiritsuke-style tip. Its flat edge profile excels at push-cutting and chopping, while the sharp, pointed tip provides precision for detail work and piercing tasks. Versatile and agile, the bunka covers everyday prep from vegetables to proteins with a bit more tip control than a standard santoku.

Listed Length: 180mm
Total Length: 311mm
Edge Length: 169mm
Heel Height: 41mm
Spine Thickness: 2.1mm
Weight:
Orientation: Ambidextrous

Blade Type: Stainless Steel
Steel Type: Cobalt Special
Steel Hardness (HRC): undisclosed
Reactive: No
Handle Type: Japanese (wa)
Handle Material: Bubinga & Horn Ferrule

  • This is a stainless steel knife made from thin, hard steel.
  • Hand wash and towel dry after use. Do not air dry or use the dishwasher. Regular neglect can lead to oxidation.
  • Avoid twisting, scraping, or use on dense or hard foods and surfaces to avoid early dulling and edge damage. If you wouldn't bite into it, don't cut it with this knife.
  • Use on wooden cutting boards only. Do not use bamboo, cheap plastics or metal cutting boards.

Dive Deeper

Medium-fine finish

We recommend sharpening by hand using whetstones starting around 1000 grit progressing to at least 4000 for this steel type and edge geometry. Finish with a monodiachrome strop for a smooth cut with a substantial bite. Finer finishes are possible, but the knife may slide on smooth foods and overall edge retention may suffer. During repair, use a super coarse stone to pass chips quickly to help keep flat bevels.

  • Avoid pull-through sharpeners and non-water-cooled mechanized systems.
  • Strops and ceramic honing rods are preferred for as-needed edge maintenance. If you have to use a honing rod to be able to use the knife comfortably, it's time to sharpen the knife.

Sharpening Supplies

Stones & Accessories selected specifically for this knife.

Arato-kun #220 Extra Coarse Grit Whetstone

Arato-kun #220 Extra Coarse Grit Whetstone

$34.00
$34.00
Bernal Cutlery Takarazukushi 1200 Grit Blue Marble Semi-Soft Ceramic Japanese Whetstone

Bernal Cutlery Takarazukushi 1200 Grit Blue Marble Semi-Soft Ceramic Japanese Whetstone

$74.00
$74.00
Bernal Cutlery Takarazukushi 4000 Grit Yellow Semi-Hard Resinoid Japanese Whetstone

Bernal Cutlery Takarazukushi 4000 Grit Yellow Semi-Hard Resinoid Japanese Whetstone

$82.00
$82.00
Arashiyama #6000 Whetstone Stone NO Wooden Base

Arashiyama #6000 Whetstone Stone NO Wooden Base

$58.00
$58.00
Arashiyama #6000 Whetstone With Nagura Stone and Wooden Base

Arashiyama #6000 Whetstone With Nagura Stone and Wooden Base

$62.00
$62.00
Bernal Cutlery Monodiachrome™ Precharged Deburring Strop

Bernal Cutlery Monodiachrome™ Precharged Deburring Strop

$40.00
$40.00



Cobalt Special

Composition: Proprietary (not publicly disclosed)

Cobalt Special is a proprietary stainless steel known for high hardness, fine grain, and strong corrosion resistance. While not a carbide former itself, inclusion of colbalt in alloys improves overall hardness heat-treat response, edge stability, and carbide refinement (of other carbide forming elements). While the exact formula is undisclosed, it performs like an advanced VG-10 variant—hard, sharp, and durable for premium kitchen and professional knives.