Casting Mold for Side Rail

Every Eames Aluminum Group chair features two aluminum side rails that establish its silhouette and provide structural support. A different shape is used for each model, and the various side rails’ distinct angles of curvature allow for a range of seated postures across the collection, from upright to reclined. Each has a deep groove that runs along its length and into which the seating pad is inserted. This L-shaped casting mold would have been used to produce side members for the reclining chair. In order to go from wooden model to finished aluminum rail, the narrow wooden model first had to be split evenly down the middle. Next, a sand-based mixture was packed around each side to create a mold in two parts. These were then fit back together to form a cavity into which molten aluminum was poured. Sand casting is often used for small production runs or prototypes because the molds themselves are inexpensive to produce (and not very durable).