a pattern set - up especially useful for making prosthetic dental appliances is assembled by attaching a plurality of refractory casts to a support member so that adjacent casts along the length of the support member are circumferentially offset with respect to one another . the casts carry expendable patterns that are connected to the support member by gating systems laid down on faces of the casts . the support member has outward protrusions supporting the weight of the casts and may be formed by a plurality of segments fitted together in end - to - end relation .