How to work with Metal Clay?

Long razor blades or a single playing card can be used to slide between working surfaces and clay designs to aid in unsticking and removing the design from the working surface. Precious metal clay must be completely dry before you can fire it. It is often easier to refine and finish a design that is completely dry. Finishing dry designs before firing also makes polishing and finishing after firing easier.

Clay has several stages of drying-semi-moist, leather hard and bone dry. Semi-moist clay is still wet and malleable but quickly begins to dry along the edges. Leather hard clay is still too moist to fire, and you can make an indentation in it with your fingernail or dental tool. Bone dry clay is completely dry and can be sanded and fired. Semi-moist and leather hard clays are the easiest stages of dryness to make repairs or add additional clay to your design. Leather-hard clay can be fragile but it is still possible to lightly file, carve, sand, make holes in and otherwise continue to refine. It is much easier to finish leather-hard clay than trying to alter the clay once it is fired to sintered metal.

When sanding dried clay, use progressively finer grits to produce a smooth surface that is ready for polishing.

Sometimes it can be easier to create clay designs and design components with dry clay. You can put them together with the use of clay slip. When creating designs in the ''dry state, '' you may encounter minor chips or dislodged clay pieces that can be repaired by remoistening the clay evenly with water and then applying precious metal clay slip to adhere pieces and fill chips. To do this, paint the slip along one edge of a remoistened piece and press the two broken pieces together. Let the join dry completely. Follow up with additional coats of thin slip over the seam until the join line disappears. Smooth out imperfections by thinning the surface of the applied slip with water. Once it is bone dry, you can sand the seam smooth and fire.

Clay slips and pastes are available premade or you can make your own by blending water with wet clay until it is the consistency of pudding. You can also collect unfired bone dry clay scraps over time and grinding them to powder in a non-porous pestle. Combine the powdered clay dust along with a few drops of water in a small jar and let it sit until all the moisture is absorbed. Add more powder or water as needed to achieve the right consistency. Blend the slip mix with a spatula or paintbrush. Seal the jar with a tight-fitting leak-proof lid. The slip needs to be thick enough to cling to the container bottom if held upside down, yet thin enough to spread easily with a spatula or paintbrush.

There are several firing options once your precious metal clay designs are ready. You can fire them in a kiln, with a butane torch, on a gas stovetop or in a pot such as cast iron over intense heat. The manufacturer's directions included with each package of clay will tell you the correct temperatures and times for each firing application.

Once fired, metal clay appears to have a white or grey residue on the surface. This is actually not a residue, it is a bumpy texture caused by an effect known as scaling, for as the silver sinters, it sticks up from the surface of the metal as the binder is burned away. If you looked under a microscope at the metal, you would see that these scales resemble the texture of sandpaper. Rubbing the surface smooth causes the metal to become smooth and it will again reflect light and appear shiny. You can use a steel brush and soapy water to give the metal a brushed finish. To give the metal a brighter polish, use an agate or steel burnisher. Tumble pieces for 30 minutes with the appropriate steel shot and burnishing compound or polish using the appropriate wheels and polishing compounds with either a rotary tool or a bench lathe.

View the free metal clay online videos in the resource gallery for more tips, easy to follow directions and complete projects. Also check out the Secrets to Art Clay Success DVD hosted by Tamara Honaman, available for purchase for your home library.