Global machine tool manufacturer Makino has launched a new horizontal machining platform optimized for five axis small part production. The linear X, Y and Z axes of the a51nx-5XU are built from the same structure as Makino’s a51nx horizontal machining center, with a rigid bed casting with three-point leveling providing a solid foundation. A tiered-column design redirects machining forces and resists deflection, including forces high in the Y-axis. The a51nx-5XU design offers dynamic stiffness and strong vibration management, complemented by high-performance linear guides for long-term reliability. The new horizontal machining center features a newly designed 5th-axis table and work-pallet magazine.
B and C axes in a single casting
With increasing demand for small-part 5-axis machining, many companies are adding aftermarket 5th-axis rotary tables to 4-axis machining centers. However, these 5-axis retrofits frequently offer less rigidity and pose several challenges in cable interface management. The a51nx-5XU avoids these issues with a single casting design that houses and integrates the B- and C-axis’ twin direct-drive motors. This single-piece casting provides high rigidity and a minimized profile that reduces interference between the spindle and worktable. All cables are concealed to the roofline of the machine’s splashguard and can be easily accessed and managed outside of the machining area. The a51nx-5XU rotary table design eliminates the stack-up errors, loss of rigidity and cable management challenges common to many table-on-table designs.
The design of the large direct-drive motors within the B and C axes provide rapid traverse rates of 75 rpm and 150 rpm to minimize non-cut time. Jacket cooling of the direct-drive motor stators and bearing perimeters reduce the risk of thermal deformation to help maintain repeatable, high-accuracy performance. The C-axis also benefits from a BT-style 50-taper Big Plus (BBT50) interface and clamping mechanism, which provides location and clamping of the workpiece within the 5-axis machine envelope.
Integral Automation Efficiency
Traditionally, one of the biggest challenges associated with 5-axis part production has been automated capabilities. Makino has designed the a51nx-5XU with a work-pallet magazine (WPM) that simplifies pallet changes in horizontally oriented 5-axis applications and facilitates unattended operation.
The WPM takes the place of a traditional horizontal pallet changer, providing manufacturers with automated load/unload capabilities for maximum machine utilization. This technology follows a similar design to that of Makino’s matrix tool magazine, allowing quick transfer of workpieces between magazine and machine worktable. The standard WPM offers storage capacity of 22 different workpieces with sizes up to 300 mm in diameter by 300 mm tall. An optional, larger capacity WPM provides storage of up to 58 workpieces with diameters up to 200 mm. Parts are mounted directly to the 50-taper dual-contact tool holders (BBT50) and stored in the WPM matrix. This capability optimizes the a51nx-5XU for continuous, unattended manufacturing in both high-mix, low-volume and low-mix, high-volume production environments.
A work data management panel allows operators to process data defined per pallet and manage work schedules. Priorities can be set and changed for each pallet, helping to accommodate for engineering changes or urgent one-off part orders. For advanced levels of scheduling control and machine networking, the a51nx-5XU can also be equipped with Makino’s MAS-A5 control system.