Mikisyo Hamono is a multigenerational blacksmith shop based in Miki City, Japan, a town with a centuries-long tradition of blade making that extends well beyond kitchen knives into woodworking tools, agricultural blades, and traditional crafts. The shop is run by Hiroyuki Nagaike — born in 1939 — who takes the craftsman name Kohsetsu Nagaike when working in his professional capacity, a traditional Japanese practice that reflects the seriousness with which he approaches his craft. His knives are made the old way, hammer-forged by hand with a precision that comes only from decades of experience.
The ko deba is a compact version of the traditional deba, Japan's dedicated fish-breaking knife, and at 103mm this one is purpose-built for smaller fish, fine filleting work, and detail cuts on herbs and small vegetables. It is forged in a ni mai construction — meaning two-layer — with a White #2 carbon steel edge clad in soft iron, ground to a traditional single bevel on the right side. That single bevel geometry is what sets a ko deba apart from most Western knives, allowing it to follow the contour of bones and skin with a level of precision that a double bevel simply cannot match. White #2 carbon steel is prized for its purity and the exceptionally keen edge it produces straight off the stones.
Carbon steel care is straightforward. Wipe the blade clean during use and dry it immediately after washing. Avoid leaving water or acidic foods on the blade for any length of time. As a single bevel knife, sharpening is done on the flat side and the bevel side separately — take care to maintain the original geometry. The soft iron cladding will develop a natural patina with use, which adds character and provides a measure of protection.Business Name: Mikisyo
Location: Miki City, Japan
Blacksmith: Hiroyuki Nagaike (Kohsetsu Nagaike)
Construction: Hammer Forged, Ni Mai (Two Layer)
Edge Steel: White #2 Carbon Steel
Cladding: Soft Iron
Edge: Single Bevel, Right Sided
Weight: 2.5 oz (72 g)
Blade Length: 103 mm
Total Length: 217 mm
Spine Thickness at Heel: 3 mm
Blade Height: 39 mm
The ko deba is a compact version of the traditional deba, Japan's dedicated fish-breaking knife, and at 103mm this one is purpose-built for smaller fish, fine filleting work, and detail cuts on herbs and small vegetables. It is forged in a ni mai construction — meaning two-layer — with a White #2 carbon steel edge clad in soft iron, ground to a traditional single bevel on the right side. That single bevel geometry is what sets a ko deba apart from most Western knives, allowing it to follow the contour of bones and skin with a level of precision that a double bevel simply cannot match. White #2 carbon steel is prized for its purity and the exceptionally keen edge it produces straight off the stones.
Carbon steel care is straightforward. Wipe the blade clean during use and dry it immediately after washing. Avoid leaving water or acidic foods on the blade for any length of time. As a single bevel knife, sharpening is done on the flat side and the bevel side separately — take care to maintain the original geometry. The soft iron cladding will develop a natural patina with use, which adds character and provides a measure of protection.











