On the fast track to special tools


Increasing customer requirements for special tools in terms of delivery time, costs and flexibility have prompted the KOMET GROUP to optimise the process chain – from the customer order to CAD and CAM through to production. Time and quality advantages are the result. A prize was awarded at EMO 2013 for this commitment: The KOMET GROUP achieved second place thanks to outstanding performance in the category CAD/CAM at the first "Machining Expert" competition held by the machine tool manufacturer DMG Mori Seiki and the Institute of Production Engineering and Machine Tools at the Leibniz University of Hanover.


The KOMET GROUP, Besigheim, is one of the leading single-source suppliers of precision tools. Managing Director Dr. Christof Bönsch describes his company as follows: "Our core competencies lie in the solution-oriented development, manufacture and sale and distribution of metal cutting tools and forward-looking services. The KOMET GROUP is constantly striving to provide the best delivery service and binding adherence to delivery dates."

Short delivery deadlines are also crucial for the important area of KOMET®  special tools which are usually developed and produced in a quantity of just one. In order to precisely implement the customer's requirements in a suitable tool with as little effort as possible, the KOMET GROUP has continuously expanded the CAx process chain and adapted it to fit particular needs. Thus, a separate CAD/CAM engineering team permanently looks after the automation of the CAx process chain with the aim of efficiently creating special tools. Oliver Glöckle, Team Leader in the area of CAD/CAM research and development, reports: "Integrated CAD/CAM processes have top priority with us. The Siemens NX CAD/CAM system, with its influence stretching from production development to machining, is therefore at the heart of our work."


In 1996, the KOMET GROUP had already introduced the Siemens NX CAD/CAM system, which is updated continuously by the employees and customised to fit requirements using self-developed tools. The CAD/CAM team looks after CAD modules as well as the fully automatic generation of relevant CAM processes. Post processors are also developed by the employees and adapted to the existing machine tools, for example, from the manufacturers DMG Mori Seiki, Stama, AXA and Chiron. Moreover, the simulation software Vericut from CGTech runs on the user interfaces of individual CAM workstations. "In order to achieve a realistic visualisation of the machining process including collision prevention, we have implemented the appropriate virtual machine models," explains Oliver Glöckle. "We then make the approved NC programs available on the KOMET network. They can be called up at any time from the machine."


Concept verification on the customer component

An essential task of the CAD/CAM team is to maintain an overview of the whole process which consists of various elements: Creating and verifying the tool concept, 3D designs using CAD modules and generating NC operations with individually extended CAM modules.

When customers enquire about a special tool, they expect the concept to be worked out quickly and flexibly. In order to overcome these challenges, KOMET has developed the capability to import complex customer drawings into the Siemens NX CAD/CAM system. This enables the component to be analysed in three-dimensional space, which allows interfering contours to be detected early on and taken into consideration. Using their own, standardised structural elements, which have been stored in CAD, the KOMET developers can put together the required special tools quickly and easily and test the concept. Geometries once created can always be used at a later ordering stage.


The standardised design of special tools using the CAD building block system is of great importance for achieving reduced throughput times and the associated lower costs. The basis for the CAD model is the workpiece to be machined. The cutting edges are selected and positioned in the 3D CAD program as required. The appropriate inserts for the selected cutting edges are saved in the system using so-called knowledge-based algorithms. This allows even an employee with little knowledge of CAD to generate the tool base body. Among other things, a virtual balancing process of the tool in the system is possible.


The result is impressive: Designing a completed special tool through a menu-guided selection of components using CAD building blocks saves around 50 percent of the development time. Modifications to the tool are also subsequently possible at any time. Moreover, it is important to store all the information required for automatic generation of the NC operations using the subsequent CAM building blocks.


One click and the NC program is ready

The CAD model must then be converted into tool paths in the CAM module. To do this, the CAD/CAM team creates a special CAM building block system that, if possible, generates all the required milling, drilling and thread cutting operations, including fully automatic machining in 5-axis mode. Customised auxiliary modules were developed to complement the standardised strategies available in the Siemens NX CAD/CAM system as an easy way of generating special applications that fit the NX CAM context. To do this, the team uses TCL (Tool Command Language) to program UserCycles in a user-oriented way. The team applies its user expertise to develop NC operations for special applications, such as spiral milling, withdrawal countersinking, single lip deep hole drilling cycle, etc. Today, roughing and finishing operations can be directly generated based on the stored raw material geometry. CAM operations are also automatically sorted according to tool in order to avoid unnecessary tool changes. This automatism results in additional significant time savings. Moreover, during NC programming, there are fewer errors of the type which can never be quite avoided completely when manually entering geometries, tools and approach/exit paths.


The CAM building block system ultimately completes the integrated process chain from the customer's enquiry to the creation of the concept and the building-block-aided CAD design through to its use on the machine. At the same time, standardisation plays a significant role in enabling changes and updates be made to individual components automatically without intervention by a specialist designer. KOMET Development Manager Dr. Niklas Kramer is enthusiastic about his CAD/CAM team: "They have produced outstanding work in recent years. Especially with special tools, the optimised process chain contributes significantly towards our customers receiving their desired special tool within the shortest time."


The KOMET process chain within the benchmark

This is the reason the managers decided to participate in the "Machining Expert" competition held by DMG Mori Seiki and the Leibniz University of Hanover which was advertised in the run-up to EMO 2013. What makes this event so special is that it recognises the company's effort and achievement in adapting and expanding the CAD/CAM process chain, whereas with many other competitions, the focus is only on the final component. Niklas Kramer explains: "We wish to demonstrate that we are also very innovative in the development and production process of our precision tools and therefore provide our customers with added value."


The organisers of the "Machining Expert" competition are the Institute of Production Engineering and Machine Tools (IFW) at the Hannover Centre for Production Technology (PZH) as well as the machine tool manufacturer DMG/Mori Seiki, who, for many years, has played a leading role in the development and production of chip-removal machine tools used for implementing complex manufacturing processes. They wish to establish a serious comparison platform that examines innovative and practice-approved process chain solutions relating to simultaneous multi-axis machining and therefore shape the future of computer-aided production.


The top-ranking nature of the competition can be seen in, among other things, the fact that the participating companies are not evaluated only on the submitted documents. Independent IFW experts travelled to the sites of the ten finalists in order to examine the actual process chain and to scrutinise it. After processing and analysing the recorded data, a jury, comprising three internationally recognised experts in the field of production engineering from Germany, Canada and Japan, eventually evaluated the entries submitted by the finalists: Prof. Dr-Ing. Berend Denkena, Director of the Institute of Production Engineering and Machine Tools (IFW) at the Leibniz University of Hanover, Prof. T. Aoyama, Director of the Department of System Design Engineering at Keio University, Tokyo, and Prof. Dr.-Ing. Yusuf Altintas, Head of Manufacturing Automation Laboratory (MAL) of the University of British Columbia in Canada. The renowned professors are leading members of the "International Academy for Production Engineering“ (CIRP).


In their qualified opinion, the KOMET GROUP achieved second place and was presented with the award on the first day of EMO 2013 in Hanover. Dr. Christof Bönsch, Managing Director of the KOMET GROUP: "We are very pleased about this award, because it is simultaneously a reward and an incentive which inspires us to continue implementing new ideas."



Institute for Production Engineering and Machine Tools (IFW)at the Hannover Centre for Production Technology (PZH)

An der Universität 2
30823 Garbsen, Germany


Machining Expert contact person:

Dipl.-Ing. Patryk-Manuel Hoppe
Tel.: +49 (0) 511 762 19848
Fax: +49 (0) 511 762 5115

Press contact

Trade press:

Wolfgang Klingauf

+49 (0) 821.524693