The LASER LINE ULTRA (left) and LASER LINE PRECISION (right) by EWAG (Etziken, Switzerland) are machining centres specialising in the laser fabrication of cutting tools made of hard and ultrahard materials such as tungsten carbide (WC), polycrystalline diamond (PCD), monocrystalline diamond (MCD), polycrystalline chemical vapour deposition diamond (CVD-D) and polycrystalline cubic boron nitride (PcBN). The capabilities of the machines include cutting edge preparation, post-sharpening, fabrication of chip breakers and cylindrical margins as well as laser-modification of ground cutting tools. An industrial robot from FANUC combined with HSK or hydrodynamic clamping interfaces allows 24/7 continuous machine operation.
Owing to its 8-axis kinematic concept and the use of an industrial laser source emitting pulses in the picosecond (LASER LINE ULTRA) or nanosecond (LASER LINE PRECISION) time regimes, complex micro geometries can be made.
The new EWAG Laser Turning Module is a software option which allows machine users of the EWAG LASER LINE machines to fabricate rotationally symmetric parts. An excellent example is a measurement probe stylus as shown in Fig. 1. It has a steel body and a monocrystalline diamond tip which was completely lasered from a solid cylinder using the LASER LINE PRECISION.
Overview image of a measurement probe stylus made completely by laser technology
close-up of the MCD spherical tip
The machine user simply needs to create a 2-dimensional DXF file which describes the rotary profile either by lines, arcs or splines as well as input a few parameterised values in the user interface. Among the values is the workpiece material in which recommended laser and machine parameters are already predefined. Screenshots of the easy-to-use interface are shown in Fig. 2.
Screenshot of the user-interface of the EWAG Laser Turning Module
with a simple click of the “show” button, a visualisation of the DXF rotary profile is possible
The software initially reads in the DXF file and automatically sorts, shifts and offsets the profile segments. Afterwards, a program is automatically generated which describes the movement of the machines axes relative to the laser beam. Before or after fabrication of the rotationally symmetric part, the Laser Turning Module can also part and face the workpiece.
Workpiece features for which the Laser Turning Module can fabricate are summarised below.
- Processable materials: polycrystalline diamond, monocrystalline diamond, tungsten carbide and zirconium oxide (ZrO2)
- Diameter ranges between Ø=0.1mm to Ø=6mm given length to diameter aspect ratios of up to 10:1
- Fabrication of features as small as the laser beam radius, i.e. ≤ 0.013mm
- Typical tolerances are less than ±0,01mm
- Together with the Profile Studio software option, planar surfaces can be fabricated
- Together with the Pro3D software option, 3D cavities can be fabricated
The Laser Turning Module is intended to process both tool and non-tool related parts expanding the customer-base for machine users of the EWAG LASER LINE machines. Tool related geometries mainly consists of blank preparation or specialty tools for chipless processing. Non-tool related geometries are manifold and include measurement probe styli, guiding pins for the tool and die industry, as well as punches for punching or surface texturing applications. Examples of laser-turned parts made by the LASER LINE ULTRA of various materials and composed of various geometrical elements are shown in Fig. 3.
laser-turned part made of zirconium oxide
laser-turned part with arbitrary spline geometry made of carbide
PCD tool used for chipless finishing of moulds made of carbide
stamping tool made of carbide used for forming lens casings for mobile phone cameras
The new EWAG Laser Turning Module is a software option available now for the EWAG LASER LINE machines. Its simplicity and user-friendly programming interface typically requires between a half a day to one day of training and can be made on-site at the customer or virtually. Owing to the use laser technology, this software option allows the processing of carbide, PCD, MCD and ZrO2 in any type of rotationally symmetric form. More importantly, all these benefits come without the need for retooling, wear or processing forces typically associated with grinding or erosion.