The Unsung Hero Behind Each Cup of Dripped Blue Bottle Coffee Yamaha Motor Newsletter (Oct. 12, 2021 No. 92)

A steady stream of coffee traces a beautiful path down into the cup below, almost like a fine indigo thread. The flavor- and aroma-rich drip coffee brewed at Blue Bottle Coffee locations worldwide all use the same dripper. Each one of these beautiful and high-quality drippers is produced in Japan in the small town of Arita in Saga Prefecture on the country’s southern island of Kyushu, a place long known for its porcelain work.

The artisans of this area craft and hand-fire these drippers in Kyuemon kilns to fashion them into fine pieces of art in their own right, and aiding in the quality control process of this 400-year-old tradition is technology from Yamaha Motor.

The Final Inspection Guaranteeing Micron-Level Precision

The drippers found at Blue Bottle Coffee stores are all handcrafted by Arita ceramicists and fired using Kyuemon kilns and techniques. Each one is an art piece and a product of incredible attention to detail in its design, construction, and beautiful silhouette, from the ridges ensuring a steady flow of coffee at the right speed to the single hole at the bottom that feeds fresh coffee into the cup below.
  This small outlet at the bottom is pivotal to creating the thread-like stream of coffee and is, in fact, one of the secrets behind each flavorful cup of Blue Bottle Coffee. Hence, its shape and size are inspected at the micron level. Their commitment to precision at the extreme is underpinned by an “unsung hero” of Yamaha Motor’s Monozukuri technology and expertise.

  The Yamaha-original inspection tool (shown at the top) is now used by Arita’s master ceramicists to check the size of the dripper’s outlet once firing is complete. The tolerances in place for deeming a dripper as acceptable for shipment are extremely small, and because porcelain ware is delicate by nature, discrepancies on the micron level arise even with the skills of a master. Any drippers that do not pass this final inspection are not shipped, making it an essential part of the process of bringing Blue Bottle Coffee’s signature flavor to its customers.

The Artisan’s Seal Certifying Top-Tier Craftsmanship

The Yamaha technicians on the inspection tool project were first deeply impressed by Blue Bottle Coffee’s incredible dedication to providing each of their customers with a great cup of coffee, but were equally full of respect for the level of precision and craftsmanship seen in the creation of the Arita ware porcelain dripper itself.
  Harutaka Goto of Yamaha’s Prototype Technology Division recalls the first meeting that was suddenly requested by Blue Bottle Coffee to discuss an inspection tool for their dripper: “Hearing of their dedication to ensure accuracy down to 1/100 mm for a cup of coffee, it inspired us to use all the technologies at our disposal to help.”
  The tool’s gauge (pictured above) is the result of a wide range of machining knowledge and technologies and the hints of this are not easily visible to the human eye. The gauge’s elliptical and tapered shape is one of them. The degree of this taper is so minute that it is indiscernible by the naked eye, but the two small lines on the tip of the gauge speak to why it has this shape. The small space between them represents the range of tolerance for meeting Blue Bottle Coffee’s quality standards, and only drippers with outlets that fall into this space are certified as finished products. To fashion such a small and precise instrument, Yamaha uses a high-end machining center that is also used to create parts for the YZR-M1 MotoGP racebike.
  “This dripper combines the passion and high demands of Blue Bottle Coffee with the centuries-long tradition and techniques of Arita ware,” explains Goto. “This high-level collaboration between people who take immense pride in their work is what leads to each delicious cup of coffee. We believe the tool we made for them is like an artisan’s seal that guarantees the level and value of their work.” But what made Goto and the team happiest was hearing praise from the artisans of Arita themselves: “The way Yamaha thought through just about anything and everything with the end users in mind and then demonstrated the technical capabilities to bring the result of that thinking to life was immensely impressive.”