The innovative "Back-Burr Cutter & Path deburring system" delivers reliable results even under the most challenging conditions
As a specialist in non-ferrous castings, the family-owned company Ohm&Häner Metallwerk GmbH & Co. KG from the quiet town of Olpe in the Sauerland region has been a globally recognized supplier and manufacturing partner for the medical technology, railway technology, construction machinery sectors, and about 30% for the automotive sector since its founding in 1961. What began with the construction of the first plant hall and the first aluminum melting furnace in-house has developed over the decades into a company with now 580 employees, operating today as a specialist for small and medium series production. Manufacturing ranges from batch size 1 up to an average annual demand of 40,000 pieces in the field of complete aluminum component manufacturing.
The company’s structure offers so much flexibility that up to 400 new parts are developed and produced annually, including many prototypes and small series, for example, for high-performance sports cars produced in manageable quantities. Above all, components used in this sector must meet very high quality standards and maintain them throughout the entire production cycle. Since lightweight construction is mandatory for such vehicles and also for future e-mobility, the material aluminum is naturally in demand, which the specialists at Ohm&Häner shape into the desired form. Complete 3D simulations of the casting process, proprietary clamping fixtures, and an in-house department for optimization and design are prerequisites established to guarantee these standards.
For a complex automotive component made of aluminum casting, intended for medium-volume production of about 400,000 pieces over seven years, the required defined deburring of two internal cross-holes with an asymmetrical contour was initially missing for final approval. Furthermore, due to the comparatively high quantity, the entire machining—including deburring—was to be performed fully automatically directly in the machine. Despite numerous tests with various tools on the market, no deburring results meeting the requirements could be achieved.
Back-Burr Cutter & Path Deburring System from KEMPF as the Only Solution
Only after contacting KEMPF field sales engineer Max Staab of the deburring specialist KEMPF GmbH from Reichenbach-Fils—who has been recognized and valued for decades as a competent and respected contact in precision metalworking—was a suitable solution actually found. The specialist in custom tools and deburring solutions places particular emphasis on the cost-effectiveness of the products offered.
By using the “Back-Burr Cutter & Path deburring system,” which consists of a spiral-fluted, high-temperature-resistant ball cutter and a specially generated NC data set for the application, bore intersections, thread exits, and even highly complex contours can be precisely and reproducibly deburred over long production runs. Especially when components are to run cost-efficiently, fully automated, and without manual rework from the production line, the Back-Burr Cutter & Path deburring system is the first choice. Unlike commonly used deburring tools that perform a linear movement relative to the cross-hole while rotating, this deburring system employs a more effective method—namely contour-parallel deburring along the edge or contour to be machined. This means that different bore diameters do not necessarily require different tool diameters and the associated time-consuming tool changes, since a ball end mill can ideally machine multiple bore diameters starting from 0.9 mm. Through the individual creation of the data set, the cutter precisely follows the contour of the component to be deburred and reliably removes any burrs, including on the backside of bores, without residue. The system is largely unaffected by burr size or contour geometry. .
Long Tool Life and Consistent Quality Exceed All Expectations
A unique feature and a key differentiator of the Back-Burr Cutter & Path deburring system lies in the NC data set, which automatically shifts the cutter's point of engagement relative to the component during machining. This prevents localized wear and achieves a significant increase in tool life.
At Ohm&Häner, the deburring system fully convinced and exceeded all performance expectations. The required machining operations were executed with process reliability and consistent quality over many thousands of components, significantly improving the total component machining time. Although the machine time increased from 1:00 min to 1:24 min, this was more than offset by eliminating all manual tasks (for deburring and inspection). Thanks to the technical deburring solution, all removable burrs could be eliminated in the machine without time-consuming intermediate steps, resulting in a substantial cost advantage.
KEMPF Expertise Beyond Standard Deburring Solutions
Especially companies seeking cost savings and further optimization opportunities in every respect due to cost pressure or increasing demands, and who have not yet found a suitable solution on the market, are well advised with the described deburring system. All programming effort is handled by KEMPF, so the customer receives a deburring system that delivers maximum performance from the start with minimal effort.
The deburring specialist KEMPF demonstrates with this innovative system that almost any deburring task can be performed directly in the CNC machine . Additional deburring with KEMPF tools was also carried out on the component’s mounting flange and was performed reliably and quickly using a spring-loaded deburring cutter. In addition to the deburring tools used, a PCD bell tool designed by KEMPF also impressed, consolidating several operations for machining the filling nozzle while leaving no burrs. The tool, ordered on short notice by Ohm&Häner, was designed and delivered by KEMPF within a very short time, ensuring the planned production start was met and sparing the customer unnecessary time and cost pressure.
Burr-Free Straight Out of the Machine
Since implementing the tooling solutions, especially in the area of deburring, Ohm&Häner has been able to produce components without any manual work and thus with consistent quality. This primarily results not only in lower costs and faster throughput times but also in fewer complaints.
As the supplier of these tools, KEMPF draws on decades of experience in this field and a correspondingly extensive range of tooling solutions. The machining spectrum is diverse, and so are the tools. Beyond the mostly “simple” applications, there are always customer requests where, due to nearly inaccessible bore intersections or complex contours, no standard tool can be used, or where previous tooling solutions simply do not deliver a process-reliable, defined, and above all secondary burr-free result. KEMPF has proven to be a reliable problem-solving partner beyond the standard portfolios of many competitors, also at Ohm&Häner, enabling the customer to achieve burr-free components straight out of the machine despite challenging conditions.
Basically, an impossible deburring task with conventional rotating deburring tools. Only the combination of a deburring cutter and CNC program allows such an asymmetrical contour to be deburred. Aluminum castings generally do not provide the necessary conditions to perform a defined deburring with the Back-Burr Cutter & Path deburring system reproducibly. Nevertheless, the customer was impressed, and no other deburring tool could achieve the desired deburring of this internal bore intersection with the required quality within the machining process.
The technical field service team from KEMPF—Max Staab, Winfried Schulte, and Raimund Hütte from Ohm&Häner, who also develop many components for the automotive industry in prototype development. After several attempts with tools from competitors, only the deburring system supplied by KEMPF ultimately proved convincing.
For the component (far left in the image), KEMPF provides not only the Back-Burr Cutter & Path deburring system (ball end mill on the left). For additional deburring operations on the component’s flange, a spring-loaded milling cutter is used (middle tool). Additionally, after evaluating the machining process, KEMPF quickly assembled a PCD bell tool from the extensive range of semi-standard PCD tools (right), which operates completely burr-free and therefore eliminates any manual work on the respective component.