UPN-01 Wire EDM

December 01, 2013

Makino announces the release of the UPN-01 ultra-precision horizontal wire EDM for micro-tolerance and fine surface finish applications. Designed with a unique horizontal wire feed system, this sub-micron level precision wire EDM provides reliable unattended operation even when working with wire diameters as fine as 0.00078 inches (0.02mm). Its oil dielectric configuration also makes it an ideal solution for high-accuracy machining of carbide and other hardened materials.

"The UPN-01 pursues the ultimate in precision micro machining, advancing closer to the world of 0.1µm machining," says Brian Pfluger, Makino's EDM Product Manager. "It delivers fine surface quality and superb accuracy every time, achieving a best surface finish of 0.17µm Rz and accuracies as fine as +/-0.5µm. This level of capability is ideal for manufacturers of fiber optics, electronic connectors, medical components, micro molding and other high-accuracy machining applications."

The UPN-01 machine travels for the X-, Y-, and Z-axes are 6.29 inches (160mm), 6.29 inches (160mm) and 1.96 inches (50mm) respectively, with additional U- and V-axis travels of +/-0.27 inches (7mm). The UPN-01 will accommodate a maximum workpiece size of 5.90 by 5.90 by 1.57 inches (150 x 150 x 40mm), with a maximum payload of 17.63 lbs (8 kg), which includes the tool holder.

The machine is also configured with an ultra-precision rotary C-axis which is used for holding and indexing of the work piece, and provides rotational positioning accuracies of +/-2 arc seconds. Due to the machine's horizontal configuration, the convention work table configuration is replaced with a frame or clamp style tooling system, which can also be automatically exchanged using the optional 16 station Automatic Work Changer (AWC) system.

The UPN-01's wire diameter range is 0.00078~0.00393 inches (0.02~0.1mm) with a minimum start hole diameter of 0.00118 inches (0.03mm). Reliable and consistent automatic wire threading is achieved by using an air injection and suction system. The maximum taper angle capability is +/-6 degrees with a 0.00393-inch (0.1mm) wire diameter and 1.57-inch (40mm) plate thickness.

From machine construction to advanced control features, the UPN-01 is designed for reliable and repeatable high-accuracy machining of micro-tolerance features.

The UPN-01 features a thermal control system that maintains constant dielectric and casting temperatures. A tightly sealed and insulated machine cover system and high-performance air conditioner control the internal machine and work zone environment temperatures to within +/-0.5 degrees C. This isolates the effects of the ambient air fluctuations during operation, and ensures high-accuracy machining by maintaining a stable machine attitude even during long hours of operation.

The UPN-01 incorporates a revolutionary new motion control system that incorporates pneumatic static pressure guideways and linear motor technology. The pneumatic guideway system, which is similar to high-accuracy coordinate measuring machines (CMMs), minimizes mechanical friction and ensures consistent high-precision movement for fine feeds, while eliminating the need for oil lubrication. Makino also engineered the UPN-01 with a unique linear motor system that further reduces movement friction and movement inertia to attain sub-micron level accuracy. The linear motor system is not design for rapid movement, but has been purpose-built to deliver the smallest possible movement increment, while overcoming traditional linear motor issues of heat generation and repulsive cogging torque of the magnetic forces.

The machine's movement positioning and repeatability accuracy is rated at +/-0.00002" (+/-0.5µm). The machine also uses a 0.0000004" (0.01µm or 10 nanometer) scale feedback system, which provides a minimum programmable increment of 0.000004" (0.1µm). The UPN-01 is capable of achieving a mechanical movement roundness of 0.000008" (0.2µm).

The UPN-01's oil-based dielectric design heightens the control of the machining spark gap for enhanced accuracy and finish quality. The machine is also fitted with Makino's newly developed MGW-V1 NC power supply unit that produces ultra-small electrical discharge pulses at 50 nanosecond cycles. Together, these features provide the precision necessary to machine micro slot details with a finish width of 0.0013" (32µm) using a 0.00078" (0.02mm) diameter wire.

The UPN-01 wire EDM machine contains several standard and optional features to facilitate long hours of unattended, precision micro-machining.

The machine's horizontal wire feed system allows for automatic threading of fine wire diameters as small as 0.00078 inches (0.02mm). This is achieved using a combination of forced air through the workpiece, and simultaneously clean start holes to eliminate troublesome wire guide maintenance. Through this methodology, a 0.02mm diameter wire can be threaded through a correctly positioned 0.03mm diameter start hole.

Simple, automatic core or slug removal is another benefit of the horizontal design. By suspending workpiece vertically, gravitational pull helps to evacuate cores from the work zone. This also helps to prevent wire break as the core or slug separates from the base material, as the blank will fall away from the wire and not create a wire pinching condition. In situations where cores are wedged between workpiece walls, an automatic jet nozzle will use dielectric fluid to flush out materials up to 0.59" (15mm) square in size, and the slug is allowed to fall freely to the bottom of the work tank where it will not cause any interference or crash potential. An extruding pin fitted with a sensor confirms core removal to facilitate completely unattended operation from roughing to finish machining. The evacuated cores can then be lifted up and recovered from the machine without sticking a hand into the dielectric fluid.

The UPN-01 does not contain a conventional machine table, and instead uses special palletized tool holders to suspend the workpiece. The work piece is loaded and unloaded in the machine using a pneumatic chuck system. The UPN-01 can also be equipped with several optional features for improved efficiency in unattended high-accuracy machining, such as the 16-Station automatic workpiece changer.

The UPN-01 also features Makino's new Hyper i control system, which features a user-friendly interface similar to that found on tablets and smartphones, making operation very intuitive and straightforward. A large 24" class HD touch-screen display provides a commanding view for operation, and the Hyper i control also features many helpful intelligent tools for the operator. Digital onboard electronic manuals, instructional training videos, and advanced process control functions provide the operator with all of the resources necessary to remain highly productive.

Related Glossary Terms

  • chuck

    chuck

    Workholding device that affixes to a mill, lathe or drill-press spindle. It holds a tool or workpiece by one end, allowing it to be rotated. May also be fitted to the machine table to hold a workpiece. Two or more adjustable jaws actually hold the tool or part. May be actuated manually, pneumatically, hydraulically or electrically. See collet.

  • electrical-discharge machining ( EDM)

    electrical-discharge machining ( EDM)

    Process that vaporizes conductive materials by controlled application of pulsed electrical current that flows between a workpiece and electrode (tool) in a dielectric fluid. Permits machining shapes to tight accuracies without the internal stresses conventional machining often generates. Useful in diemaking.

  • feed

    feed

    Rate of change of position of the tool as a whole, relative to the workpiece while cutting.

  • linear motor

    linear motor

    Functionally the same as a rotary motor in a machine tool, a linear motor can be thought of as a standard permanent-magnet, rotary-style motor slit axially to the center and then peeled back and laid flat. The major advantage of using a linear motor to drive the axis motion is that it eliminates the inefficiency and mechanical variance caused by the ballscrew assembly system used in most CNC machines.

  • numerical control ( NC)

    numerical control ( NC)

    Any controlled equipment that allows an operator to program its movement by entering a series of coded numbers and symbols. See CNC, computer numerical control; DNC, direct numerical control.

  • payload ( workload)

    payload ( workload)

    Maximum load that the robot can handle safely.

  • process control

    process control

    Method of monitoring a process. Relates to electronic hardware and instrumentation used in automated process control. See in-process gaging, inspection; SPC, statistical process control.

  • threading

    threading

    Process of both external (e.g., thread milling) and internal (e.g., tapping, thread milling) cutting, turning and rolling of threads into particular material. Standardized specifications are available to determine the desired results of the threading process. Numerous thread-series designations are written for specific applications. Threading often is performed on a lathe. Specifications such as thread height are critical in determining the strength of the threads. The material used is taken into consideration in determining the expected results of any particular application for that threaded piece. In external threading, a calculated depth is required as well as a particular angle to the cut. To perform internal threading, the exact diameter to bore the hole is critical before threading. The threads are distinguished from one another by the amount of tolerance and/or allowance that is specified. See turning.

  • wire EDM

    wire EDM

    Process similar to ram electrical-discharge machining except a small-diameter copper or brass wire is used as a traveling electrode. Usually used in conjunction with a CNC and only works when a part is to be cut completely through. A common analogy is wire electrical-discharge machining is like an ultraprecise, electrical, contour-sawing operation.