Diamond Mounted Points Guide: Shapes, Sizes & Applications

Diamond mounted points guide
Mounted point shapes A1, A11 and A12

Diamond mounted points are precision abrasive tools consisting of diamond grains bonded to a small head mounted on a steel shank. They are used for internal grinding, slot grinding, profile grinding, and deburring of hard materials such as carbide, hardened steel, glass, and ceramic.

What Are Diamond Mounted Points?

A diamond mounted point is a small abrasive wheel mounted on a steel shank, driven by a rotary tool or internal grinding spindle. The head is made from diamond grains in a resin or metal bond, and the shank diameter (typically 3mm, 6mm, or 8mm) fits standard collets.

Mounted Point Shapes and Sizes

Diamond mounted points are classified by shape (cylinder A1, A3, A11, ball A12, etc.) and by shank size. Common shapes include the A1 cylinder for internal grinding, the A11 pointed cone for deburring and slot work, and the A12 ball shape for concave radii.

Diamond vs CBN Mounted Points

Diamond mounted points grind carbide, ceramic, glass, and other non-ferrous hard materials. CBN mounted points grind hardened steel and high-alloy tool steels. Choosing the right abrasive type depends on the workpiece material you are grinding.

Mounted Point Bonds: Resin and Metal

Resin bond mounted points give a fine finish and are easy to use, ideal for finishing and tool grinding. Metal bond mounted points hold grains firmly for heavy stock removal and long life, ideal for production grinding of carbide and ceramic.

How to Choose a Mounted Point

Diamond and CBN mounted points comparison
  • Shape: A1 cylinder for internal grinding, A11 cone for slot and deburring, A12 ball for radii.
  • Shank size: 3mm, 6mm, or 8mm to fit your spindle collet.
  • Abrasive: Diamond for carbide, ceramic, glass; CBN for hardened steel.
  • Grit: Coarse (D151-D213) for stock removal; fine (D46-D91) for finishing.
  • Bond: Resin for finish and easy use; metal for heavy removal and long life.

Common Mounted Point Applications

To choose a mounted point, match the shape to the geometry you need, select diamond or CBN based on the workpiece material, pick a grit size for the finish you want, and confirm the shank diameter fits your spindle. Higher concentration gives faster removal; lower concentration gives smoother finish.

Choosing a Mounted Point Manufacturer

For a wide range of grinding rods and mounted points, contact our engineers with your material, shape, and shank size requirements.

Mounted points are widely used for internal bore grinding, die and mold finishing, deburring, and precision contour work on carbide tools, ceramic components, and hardened steel parts. They are essential accessories for tool rooms and CNC grinding machines.

Frequently Asked Questions

Q: What causes diamond mounted points to wear out faster, and how can this be prevented?

A: The wear rate of diamond mounted points depends on the material being ground, the coolant used, and the point's operating conditions, such as spindle speed and feed. Running the point at its recommended speed and load, together with proper coolant application, significantly extends the life of the diamond layer. Regular monitoring and following the manufacturer's guidelines help prevent premature wear.

Q: How do I know when it's time to replace a diamond mounted point?

A: Signs that a diamond mounted point needs replacement include a noticeable decrease in grinding performance, increased spindle power consumption, or visible excessive wear on the abrasive head. If the point starts scoring or burning the workpiece, or no longer holds its shape, the diamond layer is worn and the point should be replaced to maintain accuracy and efficiency.

Q: Are diamond mounted points suitable for all types of grinding applications?

A: Diamond mounted points are specifically designed for precision grinding of hard materials like ceramics, carbide, and certain composites where traditional abrasives struggle. While versatile, they may not be the optimal choice for every grinding task; suitability should be confirmed based on the specific workpiece material and the desired outcome.

Q: What is the correct procedure for replacing a diamond mounted point?

A: Replacing a diamond mounted point is a simple changeover rather than a wheel reconditioning operation. Switch off the spindle, remove the worn point from the collet or chuck, and insert a new point, making sure the shank size fits and run-out is within tolerance. Follow the manufacturer's instructions for mounting, and true the new point on the machine if required.

Q: How do diamond mounted points contribute to the precision and surface finish in grinding?

A: Diamond mounted points provide the cutting surface essential for achieving high precision and fine surface finishes in grinding operations. Their sharp, durable diamond crystals remove material effectively while maintaining dimensional accuracy. The quality and sharpness of the point directly affect the overall quality and consistency of the finished part.