Eliminate Manual Deburring with Back-Burr Cutter & Path and the KEMPF ibex Compensating Holder
#burrfree straight out of the machine – that’s how it should be. The team at Jelba proudly presents the aluminum castings that can now be fully machined directly on the machine. From left to right: Production Manager Rainer Pilsl, CAM Programmer Jürgen Hausmann, Machinist Alexander Sammer, and KEMPF field representative Waldemar Freund.
How a company with now over 270 highly qualified employees and international customers can emerge “out of necessity” is demonstrated by JELBA Werkzeug- & Maschinenbau GmbH & Co. KG in Hauzenberg-Jahrdorf near Passau. Today, complete systems, custom machines, fixtures, as well as turned, milled, and precision components up to 80 tons in weight are manufactured here according to customer specifications. Burr-free machining straight out of the machine is becoming increasingly important for JELBA, which is why the deburring specialist KEMPF from Reichenbach-Fils initially supported the production of aluminum components for an extruder machine with expertise and two innovative deburring systems.
In 1990, Josef Bauer and Alois Jellbauer founded the company “JELBA” with six additional employees and one apprentice, initially operating out of a converted agricultural building. In October 1992, the company relocated to Jahrdorf/Hauzenberg to its current manufacturing facility. The initial focus on contract machining such as milling, turning, and grinding, along with established contacts in the automotive supplier industry, proved successful, resulting in work being carried out around the clock and on weekends to handle the volume of orders. Accordingly, continuous investments and spatial expansions were made in the following years. Today, with 10 halls, large-scale CNC machines, a highly versatile product portfolio, and customers from the automotive and energy sectors as well as aerospace, defense technology, and plastics manufacturing, JELBA Werkzeug- & Maschinenbau GmbH & Co. KG is in higher demand than ever.
#burrfree straight out of the machine makes the difference
Although a broad range is desired, the focus remains very specialized. Over the past years, the company has built a reputation in the field of ultra-precise machining, sometimes in the 1/100 or micron range, and consequently supplies customers from the aerospace sector with their stringent quality requirements. A major strength, backed by extensive expertise, lies in machining large components, which now accounts for about 50% of production. Turning operations up to 3.4 m diameter, cylindrical grinding up to 2 m diameter, as well as component lengths up to 16 m and weights up to 80 tons are possible. It becomes clear that the deburring work involved can no longer be done manually, especially when considering not only the raw data but also the massive production equipment.
Although work on various large components runs almost around the clock, the production of these parts is not comparable to conventional mass production. Nevertheless, JELBA focuses on machine deburring even for smaller components and manageable production volumes. The goal is to unlock potential through automated deburring processes and to avoid tying up highly skilled employees with manual deburring tasks. Machine deburring also ensures process reliability and, unlike manual deburring, consistently delivers the same reproducible results.
The KEMPF ibex deburring system in use: The compensating holder with 10 mm pressure and tension compensation even works vertically, compensating for dimensional variations on the undefined casting contour. This ensures a process-reliable, consistent chamfer and prevents quality fluctuations. The machining is performed without coolant supply.
Back-Burr Cutter & Path and ibex Deburring System Ensure Burr-Free Components
Ideal for universal deburring tasks directly on the machine are the
“Back-Burr Cutter & Path deburring system” and the ibex compensating holder, introduced at AMB in September 2023, which is also offered as the “ibex deburring system” together with the special
ibex cutters. The deburring specialist KEMPF from Reichenbach-Fils aimed to eliminate the manual and overly time-consuming deburring from the manufacturing process of aluminum castings used in extrusion machines for plastics processing. Initially, the deburring of these small-series components was still performed by operators who could not keep pace with the actual machine cycle time. Additionally, consistent deburring results were not achieved. These issues were quickly resolved by KEMPF field service representative Waldemar Freund through the selection of these two innovative deburring systems.
Both systems complement each other and can cover nearly every deburring task for small and large components. This makes them ideal for replacing previous manual tasks at JELBA with more meaningful activities. The Back-Burr Cutter & Path deburring system is perfect for all defined contours, i.e., those with minimal dimensional variation. Thanks to the individually created NC data set delivered with the cutter (Back-Burr Cutter), 3D contours, bores across all diameter ranges, as well as cross-holes and bore exits can be deburred burr-free and, above all, with absolute process reliability. Another advantage lies in the offset of the cutter’s cutting point during machining, which remains unique on the market. This offset continuously changes the cutter’s engagement point with the component, enabling significantly extended tool life.
The ibex deburring system, by contrast, covers automated deburring of undefined contours and edges, such as those found on cast components. The ibex compensating holder is responsible for pressure and tension compensation and can compensate axially up to 10 mm via an internal spring available in three pressure settings. The special conical ibex cutters with Cross-Cut geometry, working in synergy with the compensating holder, are even capable of compensating radial dimensional variations, ensuring process-reliable deburring of all contours with this system as well.
The Back-Burr Cutter & Path deburring system, consisting of the shown ball end mill and a custom NC program, ensures that the BXC-98-A ball end mill with a 9.8 mm diameter precisely and reproducibly follows the defined internal contour of the cross-hole and deburrs it. Thanks to the unique capability to shift the engagement point on the workpiece during machining, very long tool life can be achieved with each operation.
Implementation of Deburring Solutions Planned for Additional Machines
Both deburring solutions were initially used by JELBA exclusively for machining the specified aluminum castings. While the ibex deburring system traces and deburrs the undefined outer contour, the Back-Burr Cutter & Path deburring system is used to deburr the internal cross-hole. Although the entire machining process was extended by about one minute, this component has since been produced burr-free straight out of the machine, eliminating the need for rework.
JELBA now intends to leverage this advantage on additional machining centers by integrating more ibex deburring systems as standard into the tool changers of several machines. This way, all deburring operations on components made of aluminum, steel, castings, as well as welded assemblies, can be handled by just two tooling systems, allowing valuable labor time previously spent on manual deburring to be used more effectively.
A section of the external contour of the aluminum cast component from Jelba, deburred and chamfered using the KEMPF ibex deburring system – shown on the left before machining and on the right after machining. The ibex cutter used, featuring a special Cross-Cut geometry and 8 mm diameter, can reliably machine the bulge on the top of the contour thanks to the ibex compensating holder employed.
Section of the bore and cross-hole contours inside the component – left before machining and right after machining with the Back-Burr Cutter & Path deburring system. The NC program enables the ball end mill to deburr this 3D contour burr-free and with absolute reproducibility across all components.