Nanbu iron kettle manufacturing process
Workshop in Minami Semboku
The accumulation of each technique creates beauty and ease of use.
The world of Nanbu iron kettles created by craftsmanship and aesthetic sense
Unique patterns and shapes, including detailed arare patterns.
Iron kettles, which are a condensation of craftsmanship and aesthetic sense, best represent the tradition and formality of Nambu ironware.
It is made using a method called the ``yakimata method,'' in which pig iron is poured into a mold made of sand.
The product is completed after going through numerous steps, including making the mold, casting, and coloring.
Also, only one product can be made from one prototype.
At the Semboku factory, you can see up close the skills of Nanbu ironware craftsmen called ``Kamashi.''
design
First, we will design what kind of iron kettle we will make. Next, we draw a full-size drawing, copy it onto a 1.5 mm thick iron plate, and cut it out to create a sawn template.
Making a mold
Using a tool called a ``gyu'' to make an unglazed mold that matches the size of the iron kettle, the mold is made by mixing foundry sand and clay liquid and turning a grinding board.
Pattern stamping
The pattern is stamped on the sawn body shape while it is still waiting for it to dry. Each piece is stamped one by one using a brass rod with a conical tip.
Mold assembly
The core is the mold that goes inside the outer mold, which is divided into upper and lower parts, the torso mold and the butt mold. Assemble the mold by inserting the core held in one hand into the body mold that lies on its side, and then covering it with the butt mold. The gap between the outer mold and the core is the thickness of the iron kettle.
Casting
Iron is melted in an electric furnace at 1,400℃ to 1,500℃, then poured into a mold using a ladle called a ``yugumi.''
Mold removal/sand removal
The cast iron hardens and is pulled out of the mold. Then, remove the sand from the core and remove the casting burrs.
Coloring
Heat an iron kettle to approximately 250℃ and use a ``kugobrush'' to bake lacquer on its surface. Furthermore, apply ``Ohaguro'' or ``Chajiru'' evenly at a temperature of about 100℃ to 150℃. Then, carefully wipe it off several times with a well-drained cloth.
Complete
The iron kettle is carefully inspected after being wiped clean, and the kettle is completed with a glaze.