The Perfect Combination for Structural Parts—Faster, Better, Lower Cutting Forces

The optimum machine tool combined with the optimum tool results in a perfect combination. And that makes cost-effective processes and impressive machining results possible. Article contributed by MAPAL.

Figure 1: Dietmar Maichel (left), project manager 3D milling at MAPAL, and Steffen Nüssle, sales director export and head of applications engineering at Zimmermann, in front of the FZH horizontal machining center (HMC).

The optimum machine tool combined with the optimum tool results in a perfect combination. And that makes cost-effective processes and impressive machining results possible. One good example of this is the cooperation between machine manufacturer F. Zimmermann GmbH and MAPAL.

F. Zimmermann developed its first horizontal machining centre (HMC) especially for the machining of structural parts for the aerospace industry. The aluminium structural parts, such as wing parts and frame ribs, are generally milled from solid material—with up to 95 percent material removal.

Fault-free machining with respect to dimensional accuracy and surface finish is crucial here. And the component structure that becomes more and more delicate with increasing material removal represents an additional challenge.

In order to make the milling process as efficient as possible even in these areas, Zimmermann has developed the FZH machining centre that offers maximum rigidity and features a robust, water-cooled travelling column. Whereas conventional machine concepts suffer from lever-related deviations with increasing slide, the guide carriage distance of the FZH increases with increasing plunging depth into the material.

In order to achieve maximum efficiency, Zimmermann employs its own patented M3ABC three-axis milling head in the machining centre, especially in the pocket corners of a workpiece. This milling head has to perform only very small swivel movements, allowing the feed rate to be kept constant and hence, the machining time to be significantly shortened.

The Beginning

At an open house in June 2017, Zimmermann demonstrated its machining centre with tools from competitors. These tools failed to meet the expectations, however, and were unable to exploit the performance of the machine.

“Why not test the performance of the MAPAL tools?” thought the project managers at Zimmermann, as MAPAL was presenting its milling cutters for high-volume machining at the event. A short time later, representatives of the two companies carried out extensive milling trials with different tools together.

Figure 2: MAPAL tools used at Zimmermann (from left to right): SPM-Rough ISO shoulder milling cutter with indexable inserts as roughing solution for diametre ranges above 25mm; SPM-Rough solid carbide milling cutter with wave profile as roughing solution for diametre ranges up to 25mm; OptiMill-SPM solid carbide milling cutter for multi-stepped semi-finishing of thin-walled structures; and SPM-Finish solid carbide milling cutter for finishing of deep pockets and delicate structures in a single pass.

The Milling Cutters

“Our goal was to choose the optimum tools from our portfolio for the machining operations on the Zimmermann machine,” explains Dietmar Maichel, project manager 3D milling at MAPAL. The tool manufacturer’s portfolio contains different milling cutters for the different tasks during the high-volume machining of aluminium structural parts. The tools are perfectly designed for use on such high-performance machines as the Zimmermann machine.

In particular, the SPM milling cutters, which are available in a solid carbide design and with PCD and ISO inserts, are being used today—a total of four tools, to be exact—at Zimmermann for the different demands of the roughing and finishing operations.

The Interaction

“The perfect combination of the machine, the three-axis milling head and the tools from MAPAL give the user a real performance boost,” says Steffen Nüssle, sales director export and head of applications engineering at Zimmermann, immediately after the first tests. “With the SPM-Rough ISO shoulder milling cutter, we achieved the best results that we have ever achieved with a tool with indexable inserts.”

The ISO tools with polished indexable inserts are the latest addition to the MAPAL SPM product range. The SPM-Rough with wave profile also surpassed the expectations for material removal with excellent smooth running.

“The complete machining of a 190x190x40 mm pocket is now effectively possible in less than a minute,” explains Nüssle.

The Present

The experts at F. Zimmermann are convinced by the MAPAL tools. “The use of the SPM milling cutters has given us a quantum leap forward in the aluminium machining. And it shows us what the perfect combination of tool and machine means in terms of performance,” says Nüssle. The tools are the first choice when it comes to machine acceptance tests or demonstrations for customers from the aerospace industry at Zimmermann.

The Future

The Zimmermann machines are suitable not only for the machining of metals. “Many of our customers manufacture parts of composite materials,” says Nüssle.

Zimmermann, therefore, also wants to mill trial parts of these materials using MAPAL tools.

“We are optimistic that with the MAPAL milling cutters for composite machining, we will also find a new secret weapon to exploit the performance of our machines even better,” says Nüssle. The corresponding plans are already in hand.

WANT MORE INSIDER NEWS? SUBSCRIBE TO OUR DIGITAL MAGAZINE NOW!

FOLLOW US ON: LinkedIn, Facebook, Twitter