Metal clay has enabled craftsmen to easily manipulate metals in their work and introduce preciousness and toughness where soft clay has failed.
Metal clay has enabled craftsmen to easily manipulate metals in their work and introduce preciousness and toughness where soft clay has failed. They are composed of minute metal particles that are mixed with an appropriate binder, and have been used for various purposes including making jewelry, beads, and sculptures. The metals used in making metal clay include gold, silver, platinum, copper, bronze and steel. These are manufactured by several firms including PMC, Art Clay, Metal Adventurers, Kempers, Makins and Hardar’s Clay. The metals used have different characteristics besides differing in prices; gold and silver are more expensive and easier to use; copper and bronze are less expensive but require specialized firing in kilns as hand held torches cannot be used. These are manufactured with different shelf lives, shrinkage rates, speed of drying and other characteristics.
After purchasing your preferred metal clay, manipulation involves shaping it into the desired products using tools and materials such as non-stick Teflon surfaces, non-stick hand oils such as olive oil, rollers, card stacks, needles, knives, and tissue blades among others. This is then dried, followed by firing in either kilns or through use of hand held torches according to the type of clay. The reduction in size that accompanies firing is what necessitates use of clay shrinkage calculator to predetermine the size of the final product. The reasons behind the decrease in size include the size of the particles hence the size of material used and the type of binder used.
Metal clay calculator is available in many websites that sell metal clay from various manufacturers. One measures the size of the unfired piece in terms of length, width, or height, which can be expressed as card stacks or mat boards. The calculation involves entering the type of clay you are using and the measurements described above, and the final measurement after firing is given to you. The units of measurement are usually in millimeters or inches, though these can be inter-converted during the calculation- you can enter figures in millimeters and get an answer in inches or vice versa according to your preference. For instance, 1mm before firing in a PMC shrinkage calculator translatesto0.75mm, which can also be given in inches as 0.03. The online shop shrinkage calculators also enable you to determine the amount of original metal clay that can give you a desired final piece.
Clay shrinkage calculator give an estimate based on the maximum rate of shrinkage as provided by the manufacturers, hence the accuracy is not guaranteed. Similar clays from different manufacturers may have different shrinkage rates, and there is also the fact that this rate is also determined by other factors such as the time taken in firing and the firing temperature, the thickness and size of the piece to be fired, and the types of binders used. It is however, a good estimate that can be relied upon whether one is engaging in professional metal clay businesses or hobbies, since the discrepancy is small and the figure is given as a range or its average, guiding you on the amount of shrinkage to expect.