Art Clay Copper Firing Guide
Art Clay Copper can be fired in a kiln or with a butane torch.
The sintering temperature for Copper is in the range of 750ºC to 1000ºC.
The melting point of Copper is 1085ºC
With metal clays we are aiming to sinter the green piece and not melt it. The completeness of the sintering process will depend on the amount and thickness of the metal clay, the sintering temperature used and the time held at the sintering temperature.
Kiln Firing of Art Clay Copper
- Pre-heat the kiln to 970ºC and
- Place the piece into the preheated kiln for 30 minutes (use proper equipment and safety precautions
when putting pieces into or taking them out of the kiln).
- Remove the red-hot piece with tongs and immediately quench in a container of cool water, to remove the oxidized layer
- Firescale oxidation can be minimised by firing the piece under a layer of carbon or by wrapping the piece in a firing blanket.
Butane Torch Firing of Art Clay Copper
- Place a piece no larger than Australian 50c piece or US Silver Dollar and 25g in weight on a firing brick
- Heat until cherry red color
- For pieces 10g or less and 1mm or less in thickness fire for at least 7 minutes;
- For pieces up to 25g and 2.5mm thick fire for 10 minutes;
- For thicker pieces extend the firing time by approximately 1 minute for every additional 0.5 mm of thickness
- After firing immediately quench in cool to remove the firescale (oxidized layer).
NOTE: If a hot, fired piece is left to cool in the kiln or open air after firing, the oxidized layer will be thicker and small bits may fly into the air. If you have fired a piece and will not be quenching it, cover it immediately after firing with fiber blanket until cool.
If you would prefer not to quench your piece, and still want to prevent firescale, you may choose to bury Art Clay Copper in activated carbon, in a
stainless steel firing pan, and fire at 750ºC. Allow to cool in the kiln.