Making Shakudō and Shibuichi
1) Make a Cuttlefish mold
- Make an impression for the ingot in a large piece of Cuttlefish
- Steady the Cuttlefish by holding it between bricks on a level surface
2) Make a charcoal crucible by putting a hollow in charcoal like that used for a barbecue
3) Hold the crucible with a mesh basket with a handle or some grips
4) Put 95% copper and 5% gold in the crucible along with borax (for flux)
5) Heat with the oxy-acetylene blow torch until the metal starts spinning and moving
6) Tip from the crucible, into the Cuttlefish mold
7) Let it cool
8) De-oxidize the outside of the ingot in 10% sulphuric acid (to clean it)
9) Wipe it dry
10) Roll to desired thickness
When cold rolling, annealing (heating up to soften) is needed regularly. The maximum width of flat metal that can be achieved is 16mm and is tricky because the edges crack etc. Creating wire is much easier.
Same as with Shakudō, but with 90% Copper and 10% Silver for a dark grey and down to 70% Copper and 30% Silver for lighter greys.