Pioneers in Machining Technology
NEW WIRE-CUT AND DIE-SINKING EDM MACHINES FROM MAKINO
In the UK, Makino is best known for its medium to large machining centres for producing anything from tool steel moulds to aircraft components in aluminium and titanium. Companies in the gas turbine business will also know the company for its VIPER grinding platforms for high-efficiency production of nickel alloy parts. Sole UK agent NCMT will, however, focused on a different side of the Japanese manufacturer’s business at the show.
Less well-known are its electric discharge machining (EDM) machines, of which it produces over 1,000 per year. At MACH 2016, two competitively priced machines were launched in the UK, a die-sinker and a wire-cut model. New Hyper i control technology will also feature. Its smartphone-type user interface with touchscreen navigation helps a novice user to match the capability and productivity of an experienced operator.
Makino EDAF3 die-sinking EDM machine
The EDAF3 ram-type EDM machine on show and its smaller counterpart, EDAF2, have a rigid and precise structure and integral thermal cooling of the Y- and Z-axis cast components to ensure long-term accuracy. Table size is 700 mm by 500 mm and the dielectric reservoir is built in to the base casting to improve thermal stability further and to minimise the machine’s footprint.
Access to the working area is unrestricted due to a programmable, three-sided drop-tank system. Unattended machining is extended by automatic electrode change and automated workpiece delivery and removal options. A fluid cooling unit maintains the dielectric at a constant temperature for stable burning conditions, while ram temperature control and a high precision, C-axis head are additional features. Electrodes weighing up to 75 kg may be used.
The machine uses the latest Hyper-i control system with an interface similar to that found on tablets and smartphones. It delivers efficient and productive results while bringing new levels of user-friendly operation to the shop floor. The control contains intelligent, intuitive and interactive functions streamlined to assist the operator at every step of the machining process. It also enables easy access and selection of power settings to produce accurate results in the fastest possible cycle times.
The new, on-board programming system, Makino Program Generator, has been designed to simplify use of the control, while generating aggressive machining programs to meet the demand for shortened lead-times on today’s shop floor. By providing answers to prompts and inputting basic data, even novice operators are able to generate efficient and safe burn routines. The new program generator also allows for programming of multiple electrodes and multiple burn locations.
ArcFree technology is standard on EDAF-series machines. In the past, if a CNC sinker developed a destructive DC arc during machining, the job would have to be stopped and both the workpiece and the electrode cleaned. Sometimes they would have to be scrapped. Makino machines have sophisticated spark gap monitoring and arc prevention circuits, so there is virtually no possibility of a destructive arc developing. Even jobs that offer less than optimal surface areas of burn due to electrode / workpiece geometry can be started with unusually high current density and relied upon to continue flawlessly, promoting operator confidence during unattended running.
Makino’s High Quality Surface Finish technology provides the EDAF with improved electrical conductivity for more consistent discharging and spark diffusion. It eliminates secondary discharges that waste energy while permitting increased efficiency of the sparks for a superior finish without lowering metal removal rates. A new power-saving mode automatically activates at the end of machining, reducing the machine’s power consumption while idle by 70 percent.
Optional performance enhancing features include Makino’s Z-axis stabiliser technology involving liquid cooling of the Z-axis ball screw and nut, allowing cavity floor surface blending to within one micron. A further option is a fine-hole configuration for precision machining of details smaller than the eye can see.
The machine can be factory ordered with the control mounted on either the left or right, facilitating easy integration of one or more machines with a variety of commercially available electrode and work pallet handling robots.
Makino U6 H.E.A.T. wire-cut EDM
Makino’s most technologically advanced wire-cut machines, the U3 and U6, was presented for the first time in the UK. Designed for ease of operation, versatility and low operating cost, the machines are the next-generation solution for improved profitability in wire EDM processes.
The new models offer enhanced performance in a design that makes competitive cycle times and high degrees of accuracy and surface finish easy to achieve. With the addition of new HyperCut technology and the Hyper-i control, even novice operators can program and produce top quality components with the most complex geometrical features. It is a significant competitive advantage for shops experiencing difficulty replacing skilled EDM operators.
The U6 was on the NCMT stand, offering X-, Y- and Z-axis travels of 650 mm, 450 mm and 420 mm respectively. Workpieces up to 1,000 mm by 800 mm by 400 mm with a maximum weight of 1,500 kg can be accommodated. Other features are reduced wire consumption rates and a choice of two guide configurations for the 0.1 to 0.3 mm diameter wire - conventional round or split V - to accommodate nearly all material types and flushing conditions.
Both the U3 and U6 are available in optional H.E.A.T. configuration, featuring Makino’s High Energy Applied Technology, which was integrated into the machine at the show. It incorporates high pressure, dual digitally controlled flush pumps and a large capacity, four-step filtration system that together provide even faster machining speeds. H.E.A.T. technology is designed to provide unparalleled wire EDM speed and accuracy in parts featuring poor or difficult flushing conditions.
An extensive library optimises cutting using standard hard brass wires, high-speed coated wires and high-taper soft wires. The extent and versatility of the entire cutting condition library ensure that all workpieces can be machined at optimum productive levels. Makino is a long-standing industry leader in reducing wire consumption. No special settings are needed, as every cutting condition including sealed and poor flush applications is automatically optimised.
U-series wire EDM machines feature an innovative design in which the entire bed casting is used as the dielectric reservoir. This design approach reduces the footprint compared with previous models and eliminates the need for additional external fluid tanks. By merging all machine components into a single base structure, improved mechanical rigidity and thermal stability are provided and the stationary table design ensures sustainable long-term accuracy. Additionally, work zone access has been simplified for ease of access and maintenance.
Makino’s HyperCut technology is a three-pass process developed to produce surface finishes as fine as 3µm Rz in standard tool steels. This performance enhancement represents a 20 percent reduction in cycle time and 14 percent reduction in wire consumption compared to the previous technology.
Makino has also developed a proprietary Pro-Tech circuit that provides electronic galvanic protection to the workpiece to prevent or at least minimise rusting and oxidation, preserving the integrity of the part without need for chemicals.