Tsuiki is a metal working technique that is derived
from the words 'hammer' and 'raise'.
The creation of vessels via this metal working
technique require an array of different tools.
A kettle alone, for instance, would require dozens
of anvil stakes and hammers to complete.
When our artisans hammer,
they hammer to shrink not stretch the copper.
The artisan has an image of the finished kettle in
their mind and their hands move to bring it to life.
Throughout the shaping process the copper hardens
and is put in a furnace to soften.
After shaping is complete, the kettle is individually coloured
using oxidizing methods developed over seven generations.
Below are just some of the different tools and techniques
that Gyokusendo artisans imploy in their work.
Hammers and mallets of different shapes and sizes line the walls and fill the cupboards.
In additional to shared tools, each artisan will also make their own, adjusting for fit and balance.
From shrinking to the final planish, the artisan will carefully choose the hammer or mallet based on the size of the work and the proces being undertaken.
Toriguchi (Anvil Stakes)
Placed and set inside carved out holes of an artisan's wooden sitting block, toriguchi are essential tools in the shaping and texturing of our copperware.
The name toriguchi (tori 鳥 bird, kuchi 口 mouth) comes from the resemblance to a birds beek.
The hundreds of toriguchi lining the walls are maintained and occasionally even reshaped by the artisans themselves.
Once the starting sheet is cut to size, the edges are lifted by sinking a large base using a mallet.
This is the first step before shaping with a hammer begins. As the sheet is pounded, wrinkles form around the edges and the artisan is careful not to let any of the wrinkles overlap.
Annealing allows copper to gain malleability. As it is worked the copper stiffens and so this process is undergone as many times as is necessary to create the final shape.
It's through this repetition of hammering and annealing that a piece will take its final form. To finish a seamless kettle, for instance, the artisan will have to anneal it roughly 15 times.
Once the initial sinking is complete, the artisan will use different anvil stakes to raise the edges further and bring the outside edges in to create a vessel.
As the material is hammered, wrinkles form at the edges and an artisan's familiarity with the material and ability to avoid them from overlapping is a marked sign of their skill.
Tinning & Baking
A small amount of tin is melted and spread thinly over the surface of the piece and then baked. The temperature of the baking will allow the artisan to create different finishing colours.
During the baking process, the artisan will rely on their experience and trained eye to know when the piece has been baked sufficiently.
This process of tinning in this way was first developed by our artisans during the early 20th century.
A mirror finished hammer is used to strike the entire piece to remove bumps and other imperfections, as well as add texture.
Small decorative motifs are chiselled onto the surface using a countless number of small edged tools.
The engraver will also specialize in chasing and repousse, where the copper surface is sunk in or pushed up to create dynamic imagary. They may also do inlay work, where different metals are placed inside a grove created on the copper's surface.
After using a sulfer solution to darken the copper surface, each piece is then carefully polished by hand. Copper salts are used after to bring out the final colour.
Manipulating the process only slightly, allows Gyokusendo artisans to create 9 different colours on our copperware.