Custom CNC Metal Machining Stainless Steel SS420 Conical Burrs for Coffee Grinder

The conical burr is the essential core mechanism—the "engine"—of high-end manual hand grinders and commercial electric coffee grinders. It consists of two mating parts: a cone-shaped inner burr with spiral, sharp cutting flutes, and a serrated outer ring burr.

To withstand the intense friction of daily grinding while maintaining food safety, we manufacture these burrs from ultra-durable, hardened metals. Our primary materials include food-grade SS420 stainless steel and high-carbon tool steels (such as 9Mn2V and 90MnCrV8), ensuring long-lasting sharpness and exceptional wear resistance.

Manufacturing a world-class conical burrs requires uncompromising industrial precision. The complex geometry of the cutting teeth leaves no room for error. Here is how we turn raw steel into a masterpiece of coffee engineering:

• High-Precision CNC Turning: We begin by feeding solid bar stock into our precision CNC turning centers. We machine the basic blank profiles for both the inner cone and the outer ring. This critical first step establishes perfect concentricity—ensuring the burr will not wobble or misalign during operation, which is vital for an even grind.

• Multi-Axis CNC Milling: Cutting the complex, sweeping spiral teeth (flutes) onto the conical surface is the most demanding step. We utilize advanced 3+2 Axis and simultaneous 5-Axis CNC milling to execute these intricate 3D toolpaths. This technology allows our cutters to move seamlessly across the curved surfaces, achieving extreme tolerances of ±0.005mm to ±0.01mm for flawless edge geometry