A press tool for a press assembly includes an additive manufactured body including a plurality of stacked layers of additive manufacturable material extending between an interior side and an exterior side. The interior side has a part forming surface including a surface profile for forming a part. The exterior side has a plurality of hollow cores defined by longitudinal walls and lateral walls meeting at joints. Press inserts are coupled to the longitudinal walls and the lateral walls at the exterior side. The press inserts are configured to be pressed inward by a pressing load during a pressing operation for forming the part. The press inserts distribute the pressing load along the longitudinal and lateral walls.