Busch® Carbide Round Cylindrical Bur

Rework micro-stone settings, break off edges cleanly, and achieve precise axial penetration without tool flex or flute chatter. The Busch® 1Z-AU Series Carbide Round Cylindrical Bur is an ultra-fine rotary micro-milling instrument engineered for master goldsmiths, diamond setters, horologists, and precision metal fabricators.

Belonging to the specialized HighTech-TOOL series, Figure 1Z-AU is manufactured from hot isostatically pressed (HIP) finest-grain tungsten carbide, providing structural density and uniform edge durability. Combining the axial penetration capability of a round ball end with the lateral milling action of a cylindrical body, the 1Z-AU features a specialized round-cut tooth pattern with a front-running blade. This unique geometry allows the tool to plunge directly into the metal along its axis, while the short cylindrical section behind the hemispherical dome can be used radially for side-milling and slot squaring. Its elongated, slender neck profile provides an unobstructed line-of-sight to the contact zone, which is vital when executing microscopic adjustments under high bench magnification. The solid carbide construction maintains dimensional accuracy and edge life across challenging materials such as platinum, titanium, 18K/14K white gold, and jewelry steel. Built on an industry-standard 2.35 mm (3/32") shank with an unmistakable gold identification ring, the series mounts directly into jeweler flexible shaft handpieces and precision bench micromotors. Available in miniature diameters from 0.20 mm to 0.40 mm (1Z-AU-002, 1Z-AU-003, and 1Z-AU-004), supplied as a single-piece package (1 pc/pack).

Why Choose Busch® Carbide Round Cylindrical Burs 1Z-AU

• Front-Running Blade Geometry: Features an overlapping front cutting tooth that enables direct axial plunging into the workpiece without deflection or skidding.

• Dual Axial & Radial Milling: Plunges axially like a round ball bur while using the short cylindrical flank behind the dome for radial slotting and side-wall trimming.

• Slender Neck Design: Tapered neck architecture provides clear visibility of the workpiece under high microscope magnification, especially on the ultra-fine 0.20 mm head.

• Hot Isostatically Pressed Carbide: HIP finest-grain carbide delivers edge sharpness, structural toughness, and wear resistance across abrasive and work-hardened metals.

• Engineered for Challenging Materials: Machines cleanly through platinum, titanium, white gold, jewelry steel, and hard non-ferrous precious alloys.

• HighTech-TOOL Gold Ring ID: Features the signature gold ring band on the neck for immediate visual recognition at the workbench.

• Universal 2.35 mm (3/32") Shank: Drops into standard jewelry flexible shaft handpieces, precision micromotors, and quick-change chucks without collet adapters.

Technical Specifications