CNC Machining Techniques at Aizaki: From Precision Milling to EDM and Grinding

Stepping onto Aizaki Vietnam’s shop floor, you immediately sense the fusion of Japanese precision and advanced technology at work. Rows of modern CNC machines hum in unison – from multi-axis milling centers to high-speed lathes – all operated by a skilled team dedicated to perfecting every detail. This human-centered approach to cutting-edge manufacturing makes the topic of CNC machining approachable, even as we deal in microns and complex geometries. Aizaki Vietnam employs key CNC machining techniques that make it all possible, and leverages these techniques to achieve tight-tolerance, one-stop manufacturing for industries ranging from semiconductor equipment to aerospace. Aizaki’s technical strength lies not just in individual machines, but in how they are integrated to deliver precision components efficiently and reliably.

5-Axis CNC Machining

5-axis CNC machining is an advanced form of milling where the cutting tool or workpiece can move in five different axes simultaneously (typically X, Y, Z plus two rotations). In practical terms, this means the machine can approach a part from virtually any angle in one setup, enabling the creation of highly complex, high-precision parts without multiple re-fixtures. Manufacturers turn to 5-axis CNC when part complexity and precision demand it. If a part has features on several sides, tight tolerances between those features, or critical angles and contours, a 5-axis machine can handle it with fewer setups and greater geometric consistency than a traditional mill. This is especially crucial in high-stakes industries like aerospace and semiconductor manufacturing. In fact, 5-axis machining reduces overall production time by performing multiple operations in one setup and minimizes the need for custom fixtures. At Aizaki, this technique is used whenever we need to machine complex 3D surfaces or multiple features in a single clamping, ensuring high accuracy and efficiency for parts that must meet stringent specifications.

Aizaki Vietnam employs modern 5-axis CNC machining centers to realize these benefits. One highlight is the Brother Speedio M140X2 5-axis mill-turn center, a state-of-the-art machine that combines milling and turning capabilities in one unit. The M140X2 features a tilting A-axis and rotating C-axis, which enable machining of complex parts with multiple surfaces and angled features in one setup. In practice, Aizaki uses the M140X2 to produce intricate components that demand both milling and turning in a single machine – for example, a part that needs cylindrical features turned and milled features at various angles can be done entirely on this one platform. Thus, Aizaki achieves superior accuracy and efficiency for our clients’ most complex parts.

Vertical CNC Milling

Vertical CNC milling is the workhorse technique of precision machining. In a vertical machining center (VMC), the cutting tool (spindle) is oriented vertically, and it moves along X, Y, Z axes to remove material from a stationary workpiece fixed on the machine table. Vertical mills excel at machining prismatic parts – those with flat surfaces, slots, holes, and pockets – by using rotating cutting tools like end mills and drills to carve material. Vertical CNC milling is used for the majority of milled components because of its versatility and precision. It’s ideal for parts that require accurate flat surfaces, drilled holes, threads, and 2.5D geometries (features on various planes). Our engineers choose vertical milling for parts like enclosures, mounting plates, frames, mold components, and any geometry that can be accessed from the top. These machines are efficient for both prototyping and production, offering a good balance of speed and precision for moderate complexity parts. 

At Aizaki, we deploy vertical machining whenever the part geometry can be effectively handled in three axes – which is quite often, unless the part has hidden features or extreme angles that demand a 5-axis approach. With advanced control systems and rigid construction, our vertical CNC machines maintain excellent accuracy even during long production runs or when cutting tough materials. A wide range of parts benefit from vertical CNC milling. Essentially, if a part’s critical features all lie on one or several faces accessible from above, a vertical mill is typically the most efficient choice.

Aizaki Vietnam’s facility includes several vertical CNC machining centers, notably Okuma Genos M560-V, Okuma MB-series vertical machining centers (MB-46VA/ MB-46VAE / MB-56VA with rotary table), and Brother Speedio R-series machines (including R650X2 and R650Xd1 with rotary table, plus R450X2). These turning capabilities support parts commonly produced in SUS303/SUS304 stainless, C3604 brass, and S45C/SS400 steels, depending on application, supporting both repeat production and custom parts manufacturing where the process route must be tailored to geometry and functional requirements. 

CNC Turning and Automatic Lathes

CNC turning is the machining process where a cutting tool removes material from a rotating workpiece (usually cylindrical), typically to create round features like shafts, bushings, or flanges. In a CNC lathe or turning center, the workpiece spins at high speed while stationary or moving tools traverse along the length and diameter to cut away material. The result is a part with rotational symmetry, such as a cylinder, cone, or complex profile along a diameter. Aizaki employs both conventional CNC lathes and CNC automatic lathes to cover a broad range of turned component needs. For larger or more complex turned parts, Aizaki uses multi-tasking turning centers that have multiple axes, as these can perform milling operations like drilling cross-holes or machining flats in the same setup as turning. For high-volume production of very small or slender parts, our CNC automatic lathes come into play. We also use automatic bar-fed lathes when we need to run unattended production – they can automatically feed in new material, allowing continuous operation and shorter cycle times per part.

For CNC lathes, Aizaki operates Okuma Genos L300-MYW (Y-axis) as well as Okuma LB3000EX and Genos-L250 machines. For automatic lathes, Aizaki utilizes Citizen Miyano BNJ-51SY6 and Citizen Cincom models (B12E, A32, A16, L20) to cover a wide size range of bar work. These turning capabilities support parts commonly produced in SUS303/SUS304 stainless, C3604 brass, and S45C/SS400 steels, depending on application. 

Precision Grinding (Surface, Cylindrical, Internal)

Precision grinding is a finishing process where a rotating abrasive wheel is used to remove very small amounts of material from a part’s surface, bringing it to exact dimensions and an extremely smooth finish. There are a few types of grinding relevant to Aizaki’s work: surface grinding (for creating flat surfaces), cylindrical grinding (for external diameters), and internal grinding (for bores or inner diameters). Unlike milling or turning, grinding isn’t primarily used to remove lots of material quickly; instead, it’s typically applied after initial machining to achieve final dimensions and surface qualities that are difficult to attain with cutting tools alone. Grinding can routinely achieve tolerances on the order of a few micrometers and surface finishes measured in single-digit microinches Ra – levels of precision and smoothness that critical components often require. 

At Aizaki, we turn to precision grinding when parts demand exceptionally tight geometric tolerances (such as roundness or flatness within 0.001 mm) or a superior surface finish for functional or cosmetic reasons. In general, if a feature’s tolerance is tighter than what our CNC mills or lathes can consistently hold, or if a surface finish needs to be extremely smooth (bearing quality), we will add a grinding step. Many high-end industrial components get a grinding process. Surface grinding typically produces the reference faces of tools and fixtures, or finishes machine parts that interface and must be extremely flat and smooth. 

Aizaki Vietnam is equipped with specialized grinding machines to perform these tasks. Key pieces of equipment include the Shigiya GPL-30B cylindrical grinding machine, the Kent KGS-63AHD surface grinder, and the Pintai NC-150 CNC internal grinding machine (ID range Φ1–45 mm). It’s a heavy, rigid machine – ideal for achieving both high accuracy and repeatability in production settings. We use this grinder to finish grind shafts, pins, and other round parts, often after heat treatment, to their final dimensions. 

Wire EDM

Wire EDM (Electrical Discharge Machining) is a unique non-traditional machining process used to cut intricate shapes through conductive materials using electricity rather than mechanical force. In wire EDM, a very thin wire (often brass, usually 0.1–0.3 mm in diameter) is continuously fed through the workpiece, and a series of rapid electrical discharges (sparks) jump between the wire (the electrode) and the workpiece, selectively eroding the material without actually touching it. Wire EDM is known for being able to cut complex profiles with very high accuracy and fine surface finish, including sharp internal corners and tiny radii that traditional milling cutters cannot achieve. 

Aizaki employs wire EDM when a part or feature is too delicate, too hard, or too geometrically complex for conventional machining. We also use EDM for features like very narrow slots or inside corners that need a sharp 90° angle – for instance, the corner of a square pocket milled with even the smallest endmill will have a radius, but EDM can achieve a much sharper corner by using a thin wire. Another strength of wire EDM is making through-hole cutouts with intricate detail, such as the profile of a gear or the lattice of a medical implant, with tolerances often around ±0.005 mm and excellent surface finish. Essentially, when the design calls for fine features or hard material machining that pushes beyond the limits of mills and lathes, wire EDM is our solution.

Aizaki Vietnam utilizes advanced wire EDM machines to accomplish these tasks, ensuring we can handle fine-detail work in-house, including the Seibu M500S. This platform supports precise, repeatable cutting for complex profiles in hardened materials, where traditional milling would be limited by tool access, cutter radius, or cutting forces. Keeping wire EDM capability on-site enables us to maintain tighter control over lead time, revision changes, and final quality verification before shipment.

CMM-Based Verification

CMM stands for Coordinate Measuring Machine, a high-precision 3D measurement device used for quality assurance. After all the machining, grinding, and finishing processes are done, the only way to be sure a part meets the specifications is to measure it – and that’s what CMM-based verification is about. CMMs are extremely accurate (in the order of microns) and are essential for validating tight tolerances and complex geometries, as it is a core part of any precision machining service. At Aizaki, every critical component undergoes rigorous quality assurance checks, often including CMM inspection, to ensure it meets our ISO 9001 certified quality standards. This process gives both us and our customers confidence that the parts will fit and function as intended in their applications.

CMM-based verification is used whenever high precision is required or when a part has many dimensions that need documentation. In practice, for aerospace, semiconductor, and medical industry parts (which constitute a big portion of Aizaki’s clientele), 100% CMM inspection of key dimensions is a common requirement. We employ the CMM for first-article inspections, in-process sample inspections, and final outgoing quality checks. If a component has tight GD&T (Geometric Dimensioning and Tolerancing) callouts – say flatness, perpendicularity, or true position tolerances that are very tight – the CMM is the ideal tool to measure those reliably. It is also used for complex curved surfaces that might be difficult to gauge with manual tools; the CMM can scan profiles and compare them to CAD models directly. 

Aizaki Vietnam’s quality lab includes the Accretech XYZAX AXCEL RDS, supported by complementary metrology systems including the XYZAX SVF NEX 3D measuring machine, Accretech Surfcom FLEX-50A surface texture measurement, and Keyence IM-7000/7020 image dimension measurement.

One-Stop Manufacturing with Integrated Techniques

A key advantage of Aizaki’s approach is how these machining techniques work together under one roof to deliver a seamless manufacturing solution. Rather than treating each process in isolation, we integrate milling, turning, grinding, wire EDM, and metrology into a cohesive workflow that matches processes to feature and verifies outcomes. Where surface treatments are required (e.g., anodizing, plating, passivation), they are managed to specification as part of an end-to-end production flow. The result is stable output for precision components, with achievable tolerances and inspection rigor defined by geometry, material, and process route.

For customers sourcing a cnc machining service, this integrated approach helps simplify supplier management while maintaining technical rigor, particularly for multi-process components that require disciplined routing and verification. For teams evaluating long-term cnc machining service partners among global machining parts manufacturers, Aizaki Vietnam’s model is designed to deliver stable output from prototype through repeat production with clear process ownership.

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About Aizaki

Aizaki Vietnam is a Vietnam-based machining manufacturer built around an integrated, multi-process workflow. We support precision machining for industries ranging from semiconductor equipment to aerospace by combining 5-axis machining, vertical milling, turning, grinding, wire EDM, and in-house metrology. Unlike many machining parts manufacturers that specialize in only one process, Aizaki’s technical strength lies in how these techniques are connected, so parts move through the right process route with fewer handoffs and clearer accountability.