30mmx40mm 5pcs Coarse Grit Bracelet and Ring Concave Diamond Drill Bit

The Bracelet and Ring Concave Cylinder Head Diamond Burs are high-precision tools engineered for shaping, hollowing, and refining curved surfaces in jewelry components—especially bracelets, rings, and pendants. The unique concave cylinder design allows for smooth contouring of rounded surfaces while maintaining clean edges and consistent symmetry.

Features:

• Concave Profile: Perfect for forming smooth, rounded channels on curved surfaces like rings and bangles.

• High-Quality Diamond Coating: Ensures excellent cutting efficiency and long-lasting performance on hard materials.

• Precision Ground: Designed for stability and control during detailed work.

• Versatile Application: Suitable for use on gemstones, precious metals, ceramics, and glass.

• Available in Multiple Sizes:

  • First size = Head Diameter

  • Second size = Concave Width

Applications:

• Jewelry making and repair

• Shaping ring interiors and bracelet channels

• Fine detailing on domed or curved surfaces

• Ideal for lapidary artists, metalsmiths, and gemstone carvers

Recommended Use:

• Use with rotary tools, flex shafts, or micromotors.

• Apply water or coolant to extend lifespan and reduce heat.

• Operate at moderate speeds with light, even pressure.