Location: Hot Metal Room
Annealing PPE: Facemask/goggles, leather apron, gloves
Hammering PPE: Ear defenders
Process
Cut copper circle using tin snips or Metal cutter. (Be aware of sharp off cuts and lever falling on head.)
Turn gas on. Ignite acetylene torch. Make sure flame is a long, blue flame.
Heat Copper until it looks like petrol spilled on a wet road.
The Colour Changing
Talking to Myself
Once heated run water over copper, dry off and place on either leather sand bag for soft indentations or wood stump for harder marks in the copper. ALWAYS work the hammer around your copper circle, outside to inside. This encourages an even bend in the bowl and is known as sinking and raising the vessel.
After several rounds of annealing the copper bowl is covered in heat scale. This is removed by soaking the bowl in a solution (white vinegar with salt crystals). I chose to file the edges of my bowl to contrast the rustic appearance of the bowls surface to the metallic shine of its original state.