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Pursuing excellence to create better tools.

Craftsmanship shaped by the needs of working professionals.

Kumagai Kajiya is a tenth-generation blacksmithing company.

For generations, we have crafted tools designed for demanding environments — from abalone hooks and oyster knives used along rugged coastlines to durable weeding tools created for everyday work.

Our craftsmanship is rooted in traditional forging and heat-treatment techniques passed down through generations of blacksmiths.
By continuously refining our tools through real-world use and feedback from professionals, we pursue strength, sharpness, and reliability without compromise.

Many of our products were born from challenges faced in daily work.
Through repeated testing and refinement, we create tools that are not only durable, but truly practical and comfortable to use.

At Kumagai Kajiya, we believe a great tool should help people work better, last for years, and perform without hesitation in harsh conditions.

This spirit of craftsmanship continues to shape every tool we forge.

  • Abalone hooks crafted to meet the needs of fishermen, with shapes that vary by region.

  • The Mekabu Cutter features a unique blade design that allows only the mekabu to be separated from wakame stems.

  • Because every fisherman handles oyster knives differently, the shape of each grip is carefully adapted to suit different users.

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Applying fishing tool craftsmanship to weeding tools.

Inspired by the challenges of everyday weeding, we developed durable and practical tools using the forging techniques perfected through generations of fishing tool craftsmanship.

After more than 100 prototypes and repeated field testing, we created tools designed to remove weeds more effectively while remaining strong enough for demanding outdoor work.

Built through real use and continuous refinement, our tools are made to perform reliably for years to come.

Striving for the Ultimate

In the early stages of development, we created flat blades similar to ordinary sickles.
However, flat blades only cut the grass above the roots, allowing weeds to quickly grow back again.

We believed we needed a tool that could remove weeds from the roots entirely.
Through more than 100 prototypes, we repeatedly refined the blade shape, angle, and handle design in pursuit of that goal.

Eventually, we developed a uniquely shaped sickle that loosens soil effortlessly when used vertically, and uproots weeds completely with its serrated edge when used horizontally.

The result was what we considered the ultimate weeding tool — the “Kusatori Kagi Kama.”

From Struggle to a Best Seller with 30,000 Units Sold Annually

When we first introduced the finished product to retailers, its unusual shape — unlike any traditional sickle — was met with hesitation.
Few were willing to even try it.

We were confident that once people used it, they would immediately understand its value.
Yet despite that belief, expanding sales channels proved to be a long and difficult challenge.

Amid many skeptical reactions, a local roadside station gave us an opportunity to sell the product.
By then, we had begun to wonder ourselves whether it would truly succeed.

However, once placed in a small corner of the store, the response was overwhelming.
The sales were so strong that the store manager called us in surprise.

Customers who used the tool began sharing comments such as, “It removes weeds unbelievably well,” and word quickly spread by recommendation.
This led to orders from other roadside stations, and the number of retailers steadily grew.

Today, our tools are sold in roadside stations and home improvement stores across Japan, with annual sales reaching 30,000 units.

Tools Designed for Exceptional Work

Kumagai Kajiya tools are built to perform in harsh environments.
Customers often tell us, “We will use them carefully and with great respect.”

But in truth, we want our tools to be used hard.

Forged using traditional blacksmithing heat-treatment techniques passed down through generations, our blades are exceptionally tough.
Even when struck against stone, they resist chipping and bending while maintaining outstanding sharpness.

As tools, their purpose is simple: to help people work better, last longer, and withstand demanding use.
For us as craftsmen, there is no greater satisfaction than creating tools that truly serve the people who use them.