SINUMERIK CNC Programming Methods

CNC programming time is absolutely decisive to achieve high productivity levels when machining individual parts or small series. This was the backdrop when conceiving SINUMERIK ShopMill / ShopTurn machining step programming. However, when it comes to large series production the situation is completely different. These are generally fabricated over longer time periods. In this case, the pure machining time is relevant for productivity, and this is where the established and powerful SINUMERIK G code programming comes into its own. The same is true for parameterizable CNC programs for part masters. However, in the field, these two basic procedures span a wide area. This is where the third procedure comes into play: With the cycle support provided by programGUIDE, the advantages of machining step programming can also be leveraged in G code programs.

ShopMill/ShopTurn was developed for programming universal milling or turning centers in shopfloor environments. In this "job shop programming" landscape, the focus is on the time from first reviewing the workpiece drawing up to when the first chips fly. But where does the name "machining step programming" come from? It clearly illustrates how a professional mentally breaks down the fabrication of a part into discrete production steps: In CNC programs, face milling, roughing a circular pocket or turning a thread undercut are precisely represented as machining steps such as these. What is crucially important is that these machining steps can be completely parameterized without any DIN/ISO know-how – so that somewhat less-experienced personnel can be quickly brought up to speed.

Not only this: Consequentially programming in machining steps allows associated machining operations to be linked, including an automatic consistency check. A message is output if a certain geometry is programmed without this being subsequently assigned to a machining step. The same applies if a drilling operation is programmed without subsequently programming a position pattern.

An additional highlight of machining step programming is that while writing program code, the component geometry is always displayed true to scale as dynamic broken-line graphics. Any errors can be immediately identified. Using a softkey or key combination Ctrl+G, operators can simply toggle between a text-based description and a to-scale representation – a second, space-consuming CNC display is not required.

A conscious decision has been made to keep the number of machining steps, as well as their associated parameters, clear and transparent for day-to-day use: "Easy-to-use" is and will always remain the key focus for ShopMill and ShopTurn. If maximum flexibility is required, then SINUMERIK with G code programming is the perfect choice.

In conjunction with SINUMERIK, DIN/ISO programming is deliberately not mentioned: The standard was last adapted back in 1983, when it represented state-of-the-art CNC technology. Today, SINUMERIK is a high-end CNC that addresses a wide range of machining technologies. To offer the complete system functionality in CNC programs, in addition to classic DIN/ISO G codes, SINUMERIK uses a wide range of CNC language commands.

The extensive set of CNC language commands allows the finest machining details to be programmed along with supporting CNC functions. The result: Especially when it comes to fabricating large series, CNC program machining times can be fully optimized. This is complemented by a high degree of flexibility, as language commands are incorporated in the readable CNC commands, which are similar to those of high-level computer languages. Parameterizable CNC programs for part masters can be efficiently created in a structured fashion by using user variables and control structures. When required, CNC users can even utilize this high-level language for machining cycles that they have generated themselves.

A text editor integrated in SINUMERIK Operate is the basis for writing SINUMERIK G code programs. It supports CNC programming by color coding specific CNC language commands – such as rapid traverse, path, feed and spindle commands. Features including Cut, Copy & Paste are also included in the command set. Further, by creating blocks, long and complex CNC programs are shown in a transparent and structured fashion. Several CNC programs can also be opened in parallel. This has a positive impact when generating programs for multi-channel applications, for example, turning centers equipped with several turrets.

programGUIDE involves SINUMERIK G code programming with integrated text editor. The difference: Machining cycles can also be parameterized for universal milling, drilling and turning technologies. This means that programGUIDE combines the high flexibility of G code programming with the benefits of machining step programming.

In addition to standard geometries for freely definable milling and turning contours, the same range of cycles is available as provided in ShopMill and ShopTurn. However, in this case, technology values such as tool and cutting rates are programmed outside the cycle. programGUIDE ensures a higher degree of flexibility, for example, for multi-channel turning machines. A tool can be changed at one turret, while the other turret is still involved in a machining operation.

Mill-turning or turn-milling? For SINUMERIK, this question is superfluous. Irrespective of whether the basis machine technology is turning or milling – the other technology can be activated using system software independent of any specific technology. Or put another way: There is a ShopMill in every ShopTurn – and vice versa. A differentiation is also not made in programGUIDE. Turning and milling operations are mapped to the specific machine kinematics using powerful transformations, such as cylinder, peripheral surface and 5-axis transformations.

Digital twins also offer all three CNC programming techniques. With SinuTrain for SINUMERIK 828D and 840Dsl or Run MyVirtual Machine for SINUMERIK ONE, precisely the same tools used in the CNC on the shopfloor are also virtually available at the PC in CNC job planning. As a consequence, graphic elements in CNC programs, i.e. the cycles and machining steps, can be ported in both directions. As a consequence, personnel can be flexibly deployed, both on the shopfloor as well as in CNC job planning at a PC.