This is also confirmed by Dipl.-Ing. Volker Nötzel, managing director at tool manufacturer Schumacher Precision Tools GmbH in Remscheid. For more than 100 years, Schumacher has been developing and producing tools for manufacturing internal threads for industry at its Remscheid site. The engineers in Remscheid have now completely digitized the design and manufacturing processes. Fully parameterized models are also used for optimization purposes in FEM solid simulations. An express service allows individually designed tools to be manufactured as single pieces or in small series with digital design within just 48 hours. 

Fully parameterized 

Together with its sister company GAP Gesellschaft für angewandte Prozesslenkung GmbH, Schumacher Precision Tools GmbH has been intensively involved in data integration and digital control methods at a scientific level for more than 30 years. At the beginning of the research, a CIM strategy was used to link all areas relevant to production and processing in terms of information technology. Twenty years ago, deep learning approaches from the field of artificial intelligence (AI) were pursued and neural networks were used for condition monitoring of CNC machining centers in collaboration with RWTH Aachen University.

Thanks to all its R&D activities, Schumacher now relies on its own modular engineering system for product development. The modular system includes the ToolDesign (TD) and ToolSimulation (TS) modules, which are used to digitally design cutting tools using variant design and to simulate and test them in use before production using FEM solid simulation. Accordingly, Schumacher Engineering works with fully parameterized tool models. Up to 180 parameters of automated variant design describe each tool in 3D space – right down to the edge rounding.

The fully digitized toolkit developed by Schumacher and GAP provides an excellent basis for intensive cooperation with E. ZOLLER GmbH & Co. KG. As reported by the owner and managing director of Schumacher and GAP, Dr. Bernd Schniering, it is in particular the personal contacts with Mr. Christoph Zoller that enable the development engineers of the companies involved to work together in a very trusting manner. 

Bernd Schniering and Volker Nötzel consider ZOLLER's expertise and competence in the high-precision measurement of all relevant parameters on tools to be particularly high. They specifically emphasize that the specialists in Pleidelsheim take on board recommendations from metrological practice. "They then optimize their measuring devices and software within a short period of time," explains Bernd Schniering.

As emphasized, cutting tool manufacturers have required tools with specifically rounded cutting edges for many years. At Schumacher in Remscheid, the process planners therefore have the appropriate production equipment—for example, vibratory finishing machines. 

As a result, they have certified quality assurance with documentation of the cutting edge parameters. They work with a »mμFocus« inspection device from ZOLLER. "After extensive comparisons of the currently available measuring methods and measuring devices, we were convinced that the »mμFocus« from ZOLLER meets our reproducibility requirements," explains Volker Nötzel. It is compact and robust. This makes it suitable for measuring both during production and as part of the final inspection. It works optically without contact, using laser light and a measuring microscope. The measuring spot is only 10 x 10 mm. Even the smallest contours and geometries can be measured with an accuracy of less than 1 μm. In addition, the »mμFocus« inspection device can easily handle complex geometries such as cutting edges and thread flanks on cutting segments on highly twisted thread drills. 

Thanks to its large vertical working or adjustment range (Z-axis), the »mμFocus« can be used to measure very small and also large tools flexibly and with repeatable accuracy. "This makes »mμFocus« particularly suitable for continuous quality assurance, especially for threading tools. Thanks to the very short setup and adjustment times, our measurement technicians can measure all tools completely, for example when manufacturing special tools in small series. Roundings with design-specified dimensional ranges between 2 and 5 μm can be measured reliably and with repeatable accuracy. This enables us to ensure that the threaded tools manufactured comply exactly with the specifications," reports Volker Nötzel. He is convinced that the optical measurement technology of the »mμFocus« inspection devices has become indispensable for further optimizing threaded tools.