The Precision of EDM vs CNC Machining

In the world of precision part manufacturing, two dominant technologies stand out: CNC (Computer Numerical Control) Machining and EDM (Electrical Discharge Machining). For businesses seeking reliable, highquality components, understanding the strengths of each method is crucial for selecting the optimal manufacturing process. As a onestopshop for custom parts, we leverage both technologies to deliver unparalleled precision and value.


cnc machining center
CNC machining is a subtractive manufacturing process where preprogrammed computer software dictates the movement of highspeed cutting tools. It mills or turns a block of solid material—such as aluminum, stainless steel, or brass—into a final part. CNC is renowned for its excellent accuracy, versatility, and speed in producing complex 3D shapes with tight tolerances, typically in the range of ±0.005 inches (±0.127 mm) or better. It is the goto solution for the vast majority of parts, from prototypes to highvolume production runs, offering a superb balance of precision and efficiency.

EDM, particularly the wire and sinker (or ram) EDM variants, operates on a fundamentally different principle. It uses controlled electrical sparks to erode material into the desired shape. A wire EDM machine utilizes a thin, electrically charged wire to cut through hardened steel with extreme accuracy, achieving tolerances as tight as ±0.0001 inches (±0.00254 mm). Sinker EDM uses a preshaped electrode to create cavities, holes, and intricate details. The key advantage of EDM is its ability to machine incredibly hard, conductive materials that are difficult or impossible for CNC cutters to handle. It excels at creating sharp internal corners, complex geometries, and microfeatures without inducing mechanical stress on the workpiece.

So, which is more precise? The answer is not a competition but a synergy. While EDM can achieve finer tolerances in specific scenarios, CNC machining provides broader geometric versatility and faster material removal rates. The true precision lies in choosing the right tool for the job.

Our onestopshop service harnesses the power of both EDM and CNC machining. We expertly guide our clients through the selection process. For most components requiring high speed and excellent surface finishes from common materials, our advanced multiaxis CNC centers are ideal. When your project involves ultrahard tool steels, intricate internal features, or exceptionally tight tolerances, our EDM capabilities provide the definitive solution.

cnc machining online

By integrating these technologies, we ensure that every part, from a simple bracket to a complex mold insert, is manufactured with the highest possible precision and costeffectiveness. Partner with us to leverage this combined expertise, ensuring your projects benefit from the optimal manufacturing strategy for superior quality and accelerated timetomarket.