WoodWorkCalc

Bits / Workshop reference

Ball-nose & tapered ball-nose bits

Choose a rounded tip for 3D contours and understand what stepover can—and cannot—predict.

How it works

The spherical tip follows curved surfaces. Adjacent passes leave a cusp; smaller spacing reduces the ideal geometric cusp but increases travel.

When to consider it

Consider ball-nose tooling for compatible 3D relief and contour finishing. Tapered tools need the actual taper and tip radius represented in CAM.

Where it does not apply

Do not enter the shank diameter as the ball diameter. A flat-surface scallop estimate does not predict finish on every slope or grain direction.

Resulting profile • cross-sectionMaterial
Cross-section of a rounded groove. Tip diameter and shank diameter are separate dimensions. Concept diagram, not to scale; guards and fixtures are omitted.

Before the first cut

  1. Confirm tip radius versus diameter, taper angle and usable cutting reach from the tool drawing.
  2. Check the shank and tapered body against the model for collisions, not just the tip.
  3. Separate roughing from finishing where appropriate; calculate scallop geometry without treating it as a cutting-load limit.

Review collet engagement & stickout · Review material setup & zero

If the result looks wrong

Stop the machine and make it safe to inspect before checking the tool or workpiece.

Visible ridges

Check stepover, raster direction and surface slope; runout and deflection also affect finish.

Deep details are damaged

Check whether the taper or shank collides before the tip reaches the intended feature.

Use the matching calculator

Calculator outputs describe geometry, time or cost—not permission to operate at those values.

Make the setup repeatable

In Machine & Bit Settings, keep these details in the standard fields, additional fields and setup notes. Record a test date only after testing that exact setup.

  • Tip radius / diameter
  • Taper and usable reach
  • Finishing stepover and toolpath direction

No cutting settings are automatically supplied or saved by this guide.

References & exact specifications

These public references explain the tool families or software features. Locate your exact part number and machine manual before setup; product families are not interchangeable.

Guidance reviewed September 2026. Diagrams are original simplified explanations, not manufacturer drawings.

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