Advantages of Using Sand Casting
Nearly any alloy: Sand castings can be readily produced in nearly any ferrous or non-ferrous alloy. Some other casting processes will melt and pour super-alloys in vacuum, but that is not typically done as a sand casting. Some materials cannot be “worked”, and must be produced as a casting.
Low tooling cost: The relatively low cost of tooling makes sand casting a process of choice for lower volume needs. Patterns do wear so the material selected for the pattern (typically wood, plastic, or metal) will depend on the expected usage quantity of the part being produced. Though not necessarily cheaper in the short run, the use of machined (or “patternless”) molds may be a cost effective option for components with expected lower usage over a longer period of time.
Versatile – Size, Weight, Shape: Sand castings can be produced in weights from ounces to 200+ tons. Through the use of cores, internal structures can be cast in place. Shaped parts rely mainly on the imagination of the designer. Most sand castings, however, will need at least some machined surfaces, either because of innate tolerance limits of the process, or the need to mate with other components.