This paper describes an aluminum casting jewelry manufacturing because of the current manufacturing costs are higher. Material or metal that is commonly used to cast jewelry is silver which aluminum Alternatives to metal. Melting is There is a close color and surface finish can be beautiful. But aluminum is a material that is cheap has studied and tested. Replacement aluminum casting body jewelry. The temperature in the baking mold before casting to test all five temperatures are 550 500 450 400 350 degrees Celsius then casting body jewelry in the next stage of the research process casting jewelry with the. aluminum to Experimental temperatures used in baking mold casting plaster for the mold temperature of 400 is appropriate. Best of casting jewelry with aluminum. The results showed that there is minimal waste and a 102 pieces of 48 pieces and has a smooth surface. A similar performance to the other materials available. Similar properties

Material selection for mold making are not only material prices wages but also there are other factors such as thermal strength shine and resistance to temperature changing that caused distortion and cracks. Preform injection molding from Polyethylene Terephthalate (PET) consumes time for drying granulated plastic in 4 – 6 hours at 140 - 160°C and injects at 280 – 300 °C. This is a very high temperature to inject into mold at 10 – 15°C in cool area. The material for mold making must be able to resist to thermal shock. Today molding machines are made of grade P20 steel (Standard JIS) to produce preform that takes long cycle time due to poor cooling. The research aims to compare the pricing time in mold making to preform injection time that made of aluminum -A7075 grade and grade P20 steel. The experiment is to make a mold that made of aluminum A7075 grade and grade P20 steel injects 15 gram preform. The PET is used to blow into a blow mold with pressure at 30 – 35 bar (Two – Stage) that are 2 bottles of 350 ML. The results of material selection for preform mold making showed that aluminum A7075 grade is cheaper 27.04% the mold price is cheaper 23.6% and consumes less cycle time than grade P20 steel.