Heller Machine Tools (www.heller-machines.com; Troy, MI) is offering a new lineup of machines for heavy-duty crankshaft milling, the RFK series, which are available in two types: for external or internal cutting. Both types of machines use two large disk-type milling cutters and both chuck the shaft between two spindles. In the case of the external machine, the cutting edges are positioned on the outside radius of the cutter; for the internal, the inserts are located along the inside radius. The tool surrounds the workpiece and it provides the cutting speed while the workpiece is rotated by the hydraulic chucks; this provides the feed. The determination of which approach-external or internal-is predicated on the form and dimensions of the workpiece. The RFK machines can handle both heavy-duty forged steel and cast iron crankshafts. Main and pin journals, cheek faces, cheek outer diameters, cheek profiles, and undercuts can be machined. The accuracy of the machining that is performed by the RFK machines is said to be so accurate that rough grinding can be eliminated. What's more, the machines are designed for flexible operation so that changing over from one workpiece type to another can be performed comparatively quickly.