Product Description
A gorgeous warm-coloured and strong clay, with an extremely simple firing schedule.
Art Clay Copper only requires a 30 minute kiln firing time and you don't need to use any activated carbon or firing pans - you can even fire it with a torch! It is a incredibly reliable clay, and the clay we recommend whole heartedly to anyone new to base metal clay.
You shape and work with Art Clay Copper just like normal silver clay. You can mould it, press textures into it, stick dry pieces together, set stones in it; exactly as you would when working with silver clay. Art Clay Copper has a shrinkage rate of 8-10% which is similar to Art Clay Silvers 8-9%.
Make sure any tools you use are clean of silver clay as this would contaminate your copper, creating an alloy which doesn't take to firing very well at all. Use separate files and abrasive papers/sponges, as these are almost impossible to clean.
Kiln firing:
Put the dried clay on shelf paper on a kiln shelf, as the copper can stick to the shelf slightly. Place in a hot kiln and fire at 970C for at least 30 minutes. When finished , don't let the kiln cool down. Yu need to quench the piece immediately from hot. Keep a steel bowl just under the kiln door, and as soon as you open the door, tip the kiln shelf over so the piece/pieces drop into the water. Every second the piece is exposed to the cooler air, it will oxidise, which will damage the piece. The quenching will allow most of the oxidised layer which occurs during firing to peel off.
We also highly recommend firing under a thin layer of carbon - this makes the quenching a little less stressful, as the carbon layer will protect the copper and you can take a little longer moving it from the hot kiln to the quenching bowl. We literally poor a little carbon on top of the piece straight onto the shelf, so the piece is just covered with a couple of millimetres of carbon. This gets poured into the quenching bowl with the piece, but can then be sieved out, dried, and used again.
Torch firing:
You can torch fire smaller Art Clay copper pieces, keep them under 35gm, and ideally not much bigger than a 50p coin as anything bigger is impossible to keep evenly heated for the whole firing.
Place piece on a firing brick and heat until cherry red (much hotter than silver needs) for at least 5-7 minutes, depending on size. Copper needs to be quenched immediately once you move the flame from it. This stops it from getting too much firescale/oxidisation. Keep a bowl of water close to your firing brick and keep it so it is level or under the edge of the fibre brick; using long tweezers or tongs, either push the piece towards the water following it with the flame until it hits the water, or move the flame away and quickly pick up/push the piece into the water.
Storing Art Clay Copper:
The surface of Art Clay Copper will naturally start oxidising and the colour will darken over time if left in the air. If you do get a darkened surface on your unfired clay - scrape most of the layer off smoosh in any small dark pieces into the remaining clay. To avoid oxidisation of unused clay, wrap it in layers of cling film tightly, then place in a grip seal bag or air tight container. Our Art Clay Storage Pot is great for keeping your clay fresh and workable. Keep the clay indoors at a moderate room temp and out of direct sunlight.
Did you know we stock embeddable copper findings? 'Embeddable' means you can add them to your clay in the wet stage and fire all at once.
Click here to see our full range of embeddable findings.