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Lost wax casting is the mon type of casting usedin the jewellery industry for production. Casting gives thejeweller or silversmith the ability to produce repeat patternsover and over again, which can substantially save on timeand labour and gold alloys are generally vacuum cast, whileplatinum and palladium use centrifugal casting whichrequires higher temperatures, is a more difficult processand therefore can be more begin with you need to make a suitable model either inmetal or in modelling wax. Modelling wax can be bought atmost reputable tool shops or ordered on line es inblock, sheet, tube or rod form. At this stage you could alsooutsource the making of the model to a professionalmasterpattern makerorwax that the model needs to be as perfect as youcan get it because any imperfections at this stage will bereplicated in each casting you produce. In creating yourmodel, consideration needs to be given to the finalweight of the item and therefore you should avoid anyunnecessary thickness in the metal while also payingattention to not making areas too thin either - for exampleclaw thicknesses. If you are planning to use stones in theresulting piece, these should also be planned out in to shrinkage on solidification, and the polishing andfinishing process, your final casting will be slightly smallerby about 1-3% so you need to allow for this in your masterpattern. And remember, if you make a wax model and casta metal master pattern from that, you need to allow forshrinkage to occur twice. Knowledge of shrinkage isinformation picked up through experience as models don’tnecessarily shrink uniformly. Remember that it is alwayseasier to take metal away than to have to add it later soerring on the side of caution is advisable. For example, fora ring, you could make it slightly smaller so you can size itonce es back from casting if the design lends itselfto doing , a master model maker or wax model maker will hav