Solid Carbide Ball Nose Spiral Router Bit

A: Scallop height is strictly determined by two geometric factors: the tool’s diameter and the programmed stepover distance. To minimize these ridges and achieve a smoother surface, you must either decrease the stepover percentage (typically setting it between 8% and 12% of the tool diameter) or use a ball nose bit with a larger diameter for the finishing pass. While a smaller stepover yields a superior finish and reduces manual sanding, it will proportionally increase the total CNC machining cycle time.

A: While Sundi’s ball nose bits feature a center-cutting geometry that allows for direct vertical plunging, our engineers strongly recommend utilizing a ramping entry (either helical or linear) whenever the toolpath allows. At the exact bottom center of a ball nose tip, the rotational cutting speed effectively drops to zero. Plunging vertically creates excessive axial pressure and heat at this dead center. Ramping distributes the cutting load across the curved edge, facilitating better chip evacuation and significantly extending the tool’s lifespan.

A: Yes, it is highly recommended. Standard ball nose bits are often preferred over flat-bottom straight bits for 3D roughing (such as terracing or raster roughing). The hemispherical tip distributes cutting forces more evenly and lacks the fragile 90-degree corners of a square end mill, making the ball nose bit highly resistant to chipping under heavy chip loads. It efficiently clears bulk material to establish the basic 3D contour before a smaller tapered bit is introduced for fine detailing.