Enamel is fired in a kiln that can reach temperatures over 1400 degrees Fahrenheit. It is most convenient to use a kiln with a door in the front (instead of on top) to fire enamels.
The amount of time in the kiln depends on the type of metal, the metal thickness, the enamel thickness, and the size of the piece.
The piece is finished firing, usually, when the enamel goes from looking like powder to a wet or glassy appearance.
3) Use protective gloves and a long-handled fork to remove the trivet containing the fired piece from the kiln and place it on an area that can handle the heat.
4) Allow the piece to cool in a warm dry place for 10 to 20 minutes.
If an enameled piece cools too quickly, the enamel will crack or break off the metal completely.
Each piece is usually fired a minimum of two times, once for each side. But can be fired considerably more times, depending on the depth of color to be achieved.