Abstract: A two-platen clamp apparatus for an injection molding machine includes a first platen having a first mold mounting surface and a second platen having a second mold mounting surface. A first rail and a second rail extend parallel to each other and to a machine axis, the first and second rails disposed at a rail elevation vertically below the machine axis. The second platen is slidably coupled to the first and second rails and translatable between mold-closed and mold-open positions. At least one force-exertion member is coupled to the second platen for clamping the first and second platens together, each clamping force exerted along an axis parallel to and offset vertically below the machine axis. At least one force-reaction member is coupled to the first and second platens for resisting separation of upper portions of the first and second mold mounting surfaces during exertion of the clamping force, each of the at least one force reaction member disposed at an elevation below the machine axis.