Continuing where last month left off, diamond turning is no longer limited to one method of turning, nor is there only one material that utilizes the diamond turning process. With continued progress of machine tools throughout the decades, machinists are no longer restricted to turning one material. From plastics to metals to infrared crystals, several elements can be turned using this machine tool. It isn’t just multiple materials that can now be turned; there are different diamond turning approaches that produce different results.

Breaking away from traditional turning — a technique that produces an even, streamlined article — this machine tool can produce objects other than optical systems, mold inserts, etc.  It all just depends on the turning method used. And among these other, increasingly more common methods, the objects that are produced may be created for decoration rather than practical use. If you’re wondering how it can be considered progress when some techniques of diamond turning create articles that don’t necessarily have a purpose, just take a look at how theses approaches are completed and what they can produce. Outlined below are two more untraditional turning techniques.


Photo courtesy of CNCCookbook

Technically considered a cutting tool used in a milling machine rather than a machine tool, fly cutters are one type of milling cutters. As they are typically used in milling machines or machining centers, the question remains: How does diamond turning come into play? Well, in previous, now antiquated procedures of diamond turning, normally only spherical objects could be produced, because of the location of the workpiece and the tool. In a new technique of fly cutting, these two items are reversed. Fly cutting has the tool mounted to the spindle, and the workpiece mounted to the slide. While traditional turning mainly created spherical objects, fly cutting changed the nature of turning — slightly. With the positions of the tool and workpiece reversed, fly cutting "turns out" elliptical or flat surfaces.



How much more elaborate can turning get? How about articles that were created with no rotational axis whatsoever? Does that make things more elaborate? At Greenlight Optics, to create optical systems, CNC machining is more sensible and feasible, so free-form machining isn’t commonly conducted at our facility. But, free-form machining is regularly used in the automotive, aerospace, and die mold industries. As this approach’s name implies, objects created through free-form machining have free-formed surfaces. However, they can be somewhat difficult to make because the machinist has multiple different tool path generation methods to choose from. But another aspect that makes free-form machining noteworthy is its precision. Free-form machining is accurate down to 1µm (that’s 1,000nm). This makes free-from machining ideal for medical technology. Without the capability of free-form machining, laser surgery, medical imaging, and other technologies of today wouldn’t be possible.