In the aerospace industry, aluminium structural parts, such as wing parts and frame elements are generally milled from solid material. A buy-to-fly ratio of 22 (95 %) is not uncommon here.

New machine generations that have sufficient drive power and the necessary spindle speeds make the high-performance machining of aluminum parts cost effective. MAPAL has developed a new range of aluminium roughing mills especially for these machines.

The OptiMill-SPM (structural part machining) high performance mill is equipped with a cutting edge that makes up 60%-80% of its diameter. This represents the maximum contact depth for the high-performance milling of aluminum.

Thanks to a highly positive cutting edge geometry and optimised chip flutes, the cutting force of PCD mills is reduced by up to 15%. Even when milling on standard machines, this reduction in cutting force results in more efficient machining parameters, and hence in improved performance.

​The bottleneck form of the mill prevents the tool from bending during the machining process. Another advantage of this stable design 
is the clearance that is created between the wall of the part and the mill shank. This prevents chips from scratching the wall of the part, particularly if it has deep pockets.

OptiMill-SPM tools with internal cooling are available in a solid carbide design with a diameter range of 6 to 32 mm or in a PCD design with a diameter range of 6 to 50 mm as part of the standard range. The range of products also includes variants with the well-known CFS replaceable head system.

With an extensive and diversified range of tools for reaming, drilling and milling and many years of process experience, MAPAL places a huge focus on aluminium machining.

Two new products address additional customer requirements:

1. The PCD milling cutter FaceMill-Diamond-ES
2. The indexable insert milling cutter NeoMill-T-Finish

Both of these increase economic efficiency in aluminum milling applications.

The milling cutters have fewer cutting edges than the established FaceMill-Diamond tools, making them a more cost-effective and an “Economical Solution”. With a diameter of 50mm (1.96"), for instance, the FaceMill-Diamond-ES has five cutting edges, while the classic FaceMill-Diamond has twelve. Another difference is the area of application: The FaceMill-Diamond-ES is suitable for shoulder milling, trimming and machining thin-walled parts, as well as face milling.

The new milling cutter is available in the diameter range of 32mm(1.26") to 80mm (3.15"). Dimensions have not changed in comparison to existing FaceMill-Diamond models. Accordingly, it can be used directly in existing production, if, for example, the larger chip space of the new tools should be used. Cutting depths of up to 10 mm are easily possible.
All milling cutters in the FaceMill-Diamond-ES series can be reground and re-equipped. They are exclusively available as milling cutters for arbor mounting.

With the new system, customers can also use other cutting materials in addition to the PCD-tipped inserts, depending on application and workpiece material, such as uncoated carbide or carbide with CVD diamond or PVD coating. This means the optimum cutting material can be used for aluminium workpiece materials with different silicon content and casting processes (sand casting, pressure die casting and permanent mould casting).

The indexable inserts each have up to four usable cutting edges. An optimum version is available for every customer and every requirement, offering maximum economic efficiency and process reliability.
A patent-pending insert arrangement system is what makes the new milling cutter unique. The main inserts, which perform stock removal of up to 2.5mm (0.98"), are attached to the circumference. A wide finishing insert arranged axially is responsible for the ability to reach surface roughness levels of Rz = 1.5 µm.

The innovative system enables homogeneous wear and tear on the cutting edges: Thanks to the special arrangement of main inserts and wide finishing inserts, all main inserts have the same feed per tooth, smooth running for good surface quality and no burr formation.

The resulting longer tool life is reflected in a lower cost per part with a high level of process reliability.
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Each tool is adapted specifically to the customer’s requirements. Maximum economic efficiency and productivity are the top priority. The tool body is usually made from steel. If weight restrictions are in place, MAPAL manufactures the tool body in aluminum or with a weight reduction bore.

The NeoMill-T-Finish can be configured in the diameter range from 50mm (1.97") to 315mm (12.4") and can be ordered as a monolithic unit or an adaptive unit for milling holders with arbor.

​Cutting speeds of up to 6,000m/min (236,220IPM) and feed rates of 2.5mm (0.98" IPR) per revolution are possible in use.