A CLAYTIVITY project cannot be taken home immediately after it has been made – it has to be dried out and bisque fired in a kiln first and this process can take up to three weeks before the project can be returned.
Read on to learn a little more about this process..
It is very important to let the clay dry out thoroughly (about 7 – 15 days) otherwise when it is heated up in the kiln, as the water turns to steam and expands rapidly the project will explode and shatter into hundreds of little pieces which will scatter over everything else in the kiln. With thicker pieces or bigger lumps of clay, like the body of a snowman, you can’t always tell if it is completely dry as it may look dry on the surface but in the centre it may still be a little moist so it’s best to be patient and wait rather than risking a catastrophic mess happening inside the kiln!
When the projects are dry, they are carefully loaded into the kiln on ceramic shelves. When a shelf is full, another shelf is added on special shelf supports, like another floor level in a house, so more projects can be loaded onto that shelf. Then one more shelf can be added and filled before the lid is closed on the kiln and is ready to start firing.
A small cone is placed in the switch mechanism, the kiln lid is then closed and the kiln is switched on. Coils of electric elements heat up the kiln to about 1000 degrees centigrade which takes about 5 – 6 hours, depending on how many projects are in the kiln. At this temperature, particles of clay melt and fuse together changing into bisque, a material that is very hard when it has cooled down and the projects glow with red hot heat like the embers in a campfire. When the kiln reaches this temperature, a small cone which has been placed in the switch mechanism starts to melt causing the kiln to switch off.
After about 12 hours when the kiln has cooled down the lid is opened and the kiln is unloaded. The projects are no longer clay projects but are now bisque, very hard and white with a beautiful surface.
The projects are wrapped in newspaper and boxed up, ready for delivery or collection but they are not finished yet – there is one more thing to do and that is usually up to the client. Paint them with acrylic colours and for the final touch finish with an acrylic gloss or glitter paint and we are sure you will be delighted with your project!