2019 Technology Review: Machining

Vertical Machining Center Reduces Handwork in Complex Molds

Makino’s V90S is a next-generation vertical machining center (VMC) for five-axis continuous processing. This high-precision VMC evolved from Makino’s three-axis Vi series and has an updated spindle and tilting and rotating axis unit that Makino says supports tighter tolerances and decreased machining and polishing times. The V90S combines quick machine movements and accuracies with software for high-speed motion control. Makino says that the V90S is designed for high-speed finishing of multifaceted, 3D contours and that it cuts cycle times and reduces handwork in complex dies and molds.

To maximize work-zone volume and load capacity, the V90S can accommodate workpiece sizes up to 2200 x 1500 x 700 mm and weighing 5000 kg. Examples of such workpieces include the inner panels of automobile doors and front grilles. The X, Y and Z axes (2000 x 1300 x 800 mm, respectively) provide swift movements with rapid traverse rates of 58,000 mm/min and cutting feed rates of 40,000 mm/min. The V90S’s A axis tilts at ±30°, which is wide enough to machine holes for an angular pin, while the C axis rotates at ±60°, ensuring that the tool tip can be positioned to provide optimum contact with the workpiece. Makino says that this extends tool life, provides the required surface finish and minimizes post-machining hand processes.

Makino says that the V90S is equipped with a unique wide-open front door and open-ceiling design so that the vertical machining center provides improved ergonomics for operators to load and unload workpieces and to open ceilings for overhead crane access to the worktable. The work zone of the machine is designed to move chips into internal troughs which are evacuated with the lift-up chip conveyor. Makino says that as a result, the V90S extends tool life and provides exceptional surface finishes even in applications that require fine tool blends and matches.

Double-Column Machines Combine Speed, Stability

The latest additions to Hurco’s BXi CNC machine series are the BX50i, with X-, Y- and Z-axis travels measuring 37.4" × 53.2" × 23.6", and the BX60i, with X-, Y- and Z-axis travels measuring 52.1" × 63" × 27.6". The rigidity and thermal stability of the double-column design, combined with the weight of the machines, provide accuracy and improved surface finish capabilities. Designed for the moldmaking and aerospace industries, the machines are suitable for high-speed machining applications that require tight tolerances. The double-column design is said to minimize machine distortion and thermal deformation. Also contributing to rigidity is a ladder-style bridge. This design supports the head casting, keeps the spindle centerline close to the supporting structure and isolates the bridge from part weight.  

The machines feature integrated WinMax control software and the UltiMotion motion system. The control software supports multiple programming methods, including conversational programming, NC programming, and a Hurco-specific feature called NC/Conversational Merge.

The UltiMotion system is designed to determine the tool’s optimal trajectory, ensure consistent programmed feed rates and reduce cycle time. Compared to conventional systems, it is said to improve cornering velocity and reduce machine jerk. It includes up to 10,000 blocks of dynamic look ahead and adapts to toolpaths. It improves on CAM output through improved handling of machine mechanics and dynamics.

The BX50i has a table size of 59.1" × 37.8" and a table load capacity of 5,512 lbs. Its axes run as fast as 1,535 ipm. It features direct drive ballscrews. Its motorized, 47-horsepower spindle can rotate as fast as 18,000 rpm, and its spindle taper is HSK 63A. Spindle torque ranges to 88 ft-lbs at 2,800 rpm. It has 30 automatic tool changing stations and weighs 28,600 lbs.

Five-Axis Line Targets Die/Mold, Aerospace

Takumi USA’s series of five-axis machining centers includes the U600 model (XYZ/AC Travels: 24.4" × 39.4" × 19.7"/+30°-110° × 360°) and the U800 model (XYZ/AC Travels: 31.5" × 39.3" × 29.5"/±120° × 360°). Both machines utilize a trunnion-style, two-axis table and the Heidenhain TNC 640 control. The machines are designed for die/mold, aerospace and high-speed applications that require tight tolerances.

The U800 isa gantry machining center with a high-torque table (800 mm platter) with an 80-rpm, twin-torque motor in the A axis and a 100-rpm, single-torque motor in the C axis. It will be shown cutting a  20" tall, 4140 steel replica of the famous Venus De Milo sculpture to showcase its rigidity, speed and surface finish capability.

Handling System Eases Operator Access, Provides Storage

Hermle Machine Co.’s C 42 machining center will feature the company’s HS Flex work handling system. The handling system is said to be a powerful and compact automation tool that fits both the company’s Performance-Line machining centers and High-Performance-Line models. A flat mineral casting bed holds three axes of the handling unit and offers ergonomically convenient access for the operator.

The system also functions as a storage module, with one module installed as standard and an optional second module available. The modules are structured as a rack, offering customization in the pallet/workpiece arrangement. Up to four rack shelves can be ordered with a total ranging to 20 pallet storage spaces per module, providing up to 40 pallet storage spaces when two modules are installed.

Also on display is the C 650 machine model, the largest machine on the company’s Performance-Line series.