Complex fixtures and composites layup tools are also examples of milled parts that might have a similar complex 3D shape. High speed machining is an important topic for die/mold machining, because of the need to take light milling passes productively in order to realize both the required geometry and the required surface finish. Hard milling is another important issue, because many molds and dies are milled in their hardened state, to prevent heat treating from affecting the geometry. In addition to milling, EDM is another machining technology used to produce dies and molds. For certain machined features and for certain hard workpieces, the more efficient way to produce the 3D form may be to mill that shape into a ram or sinker EDM electrode, then use that electrode to machine the shape into the final die or mold tooling. Hole making is another class of machining operations relative to die/mold machining. Dies and molds are assemblies that often consist of plates and other components with various holes for cooling, venting, ejection and other necessary functions of the tooling. Producing an injection mold, for example, can involve considerable drilling, tapping and helical milling of various holes in order to produce the needed components.