Diamond Ball Burr 3.1 mm EXO PRO by EXO — rotary tool bit for grinding and engraving

Diamond Ball Burr 3.1 mm EXO PRO by EXO is a rotary tool bit with a spherical diamond-coated head designed for precise grinding, shaping and engraving on hard materials. The 3.1 mm ball profile provides controlled contact area for detailed surface finishing, cavity profiling and deburring. The bit is compatible with standard rotary and die grinders and is intended for use where durable abrasive performance and dimensional accuracy are required.

Advantages

The diamond-coated spherical head delivers long-lasting abrasive action and consistent cutting performance on ceramics, glass, stone and hardened alloys. The compact 3.1 mm diameter ball allows access to small radii and tight contours while maintaining stability during rotation. The tool bit is balanced for steady operation in standard rotary and die grinders and offers predictable material removal rates for fine finishing and detailed engraving.

Suitable for

• Precise engraving and detailed carving on glass and ceramics
• Shaping and profiling small cavities in stone and composites
• Deburring and finishing hardened metal parts and alloys
• Model making, jewelry work and dental laboratory tasks requiring fine detail
• Surface refinement before polishing or coating

Key specifications

• Head shape: spherical (ball)
• Head diameter: 3.1 mm
• Abrasive type: diamond-coated surface
• Shaft compatibility: fits standard rotary and die grinders
• Primary materials: suitable for ceramics, glass, stone, hardened alloys
• Typical applications: grinding, shaping, engraving, deburring, cavity profiling

How to use

Secure the rotary tool bit in the collet or chuck of a compatible rotary or die grinder, ensuring firm clamping and correct alignment. Operate the tool at recommended speeds for diamond burs and apply light, even pressure while moving the bit across the workpiece to avoid overheating and premature wear. Use steady, controlled passes to achieve the desired profile or surface finish, and allow periodic cooling breaks when working on heat-sensitive materials. Clean the bit after use to remove debris and maintain abrasive effectiveness.

Usage recommendations

For best results, select motor speeds appropriate for the work material (moderate to high speeds for stone and glass, lower speeds for delicate ceramics) and use water or an appropriate coolant when required to reduce heat and prolong tool life. Wear eye, respiratory and hand protection, and perform work in a well-ventilated area. Replace the bit when abrasive performance diminishes to maintain precision.