Retrofitting with the Right Partners Pays Off

With his innovation of the rotating center, Karl Friedrich Bruckner set significant changes in motion over 100 years ago. Today, the third generation at Karl Bruckner GmbH in Weinstadt, Swabia, is already responsible for the production of high-precision centers for turning and grinding as well as face chucks, face drivers and quills. The products are supplied as original equipment to renowned German machine manufacturers and to customers all over the world.

In the recently completed new building, 64 employees take care of all customer needs on an area of around 6,500 m2, including 35 well-trained specialists in production. The demands are high, as the precision required for the clamping devices must be achieved consistently. Production is carried out across all types of machining, using machines capable of achieving this high precision with robust process stability. To date, this has included the Ceres 330 universal internal and external cylindrical grinding machine from Schaudt Mikrosa BWF, which was purchased in 2004 and was designed for workpieces up to 300 mm in diameter.

Production foreman Marc Sigle, who is responsible for the smooth flow of production, is not only responsible for the machining performance of the machines, but also shares responsibility for their procurement and replacement. When it became challenging to achieve the required accuracy with the Ceres 330, Marc Sigle explored various options: “In terms of dimensional accuracy and process stability, the Ceres has been exemplary over the years. The machine has a relatively simple design, but was perfectly matched to our product and ran as a pure production machine for us all those years without any problems”, recalls Sigle, who worked on the Ceres himself for several years and knows it inside out. As it turned out, this was advantageous in every respect.

Retrofit Challenge
The general question about whether retrofitting old machines is worthwhile is also affirmed by Jörg Huttelmaier. “One of the arguments in favor of a retrofit, apart from the lower costs, is that the machine operator knows the machine well and therefore does not need any training time. The space requirement remains the same, and as a rule the foundation can continue to be used”, says Jörg Huttelmaier, adding, “Sustainability and recycling are important topics today. From an environmental point of view, a retrofit is always a good thing, because the CO2 footprint is much lower than with a new machine.“

Jörg Huttelmaier continues, “Retrofitting is not about simply replacing all the old parts with new ones. Rather, a decision must be made with a sense of proportion and experience as to which process should be used where. Our retrofit procedures always start with a detailed survey of the machine and documentation of all damage. The machine is completely disassembled for this purpose. The individual measures and steps of the general overhaul and the customer’s requirements are then recorded in a specification sheet, which is then agreed with the customer.”

For the Ceres 330, the main challenge wasn’t the condition of the machine, but rather the requirements of the machining programs - in other words, the control system. Initially, they considered replacing the old control system with a new one from the same manufacturer. But the program adaptations, which were essential for Bruckner, would have required an immense amount of programming because, among other things, special features for internal grinding and dressing were needed. However, this would only have been possible at an equally immense cost with the self-contained software packages provided by this manufacturer.

The HDC specialists had gained a picture of the requirements on site before the project began. “At HDC, we have our own programmers who write programs for a wide variety of control systems. But in this case, the effort and the associated costs went far beyond the normal level”, says Jörg Huttelmaier. “Our assessment was that we needed a CNC control and software partner whose system was comprehensively flexible and open enough to implement the wide range of machining requirements that Bruckner had for the Ceres 330.”

For this problem, Jörg Huttelmaier used his contacts to Marc Riedl, sales manager for southern Germany at the control and software manufacturer NUM. The intensive discussions revealed that NUM was exactly the right partner for the application at Bruckner.

Control software that leaves nothing to be desired
NUM has a global presence as a manufacturer of high-end CNC solutions and is particularly successful in the markets of Asia, the USA, France, and the Scandinavian countries. In Germany, Austria, and Switzerland, the company is primarily known for its control software, which is available in different variants for milling, turning, grinding operations, and gear cutting.

The Swiss company, headquartered in Teufen, offers a wide range of perfectly matched products such as CNCs, drive amplifiers, and motors. In addition, they provide training, support, and service lines. NUM CNC controls are characterized by a complete openness of the system to the operator, enabling easy implementation of their know-how and perfect adaptation to a wide range of machines. To fully leverage this flexibility, NUM provides the necessary development tools, or the NUM staff can implement special functions according to customer specifications and put them into operation.

At NUM, the focus is always on the customer’s needs. This means that the various HMI are pre-configured, but can be adapted depending on the application. A team of specialists at NUM takes care of this customization work. “Our scalable and flexible Flexium+ series CNC systems are excellent for retrofitting because they can be perfectly adapted to any need and any machine”, Marc Riedl elaborates.