PLASTER MOLD
CASTING/PRECISION
SAND CASTING
Patterns are made in halves on separate plates (cope and drag) or single plate (match plate) and patterns are placed in a box (flask) and sand with binder is packed around the pattern OR a ceramic slurry is poured over the pattern and allowed to harden. The pattern is removed (plaster molds are oven dried for several hours) and the 2 flasks are placed together and molten metal poured into the cavity created. Internal areas are cored using other types of sand with binders. Process is not usually automated.
-Castable aluminum and zinc
alloys
-Good dimensional accuracy
-Excellent surface finish, 125 RMS
and better
-Requires little or no draft
-Medium and short run (good for
prototypes)
-Low to moderate tooling costs
(short lead times)
-Very little restrictions to design
