Guhring 9038990002500 Micro Drill Bit 0.0098 in Carbide

Product Description

The GUHRING 9038990002500 is a solid carbide micro drill bit engineered for precision drilling in cast iron and steel. Belonging to Series 3899, it carries a Wire Gauge size of 87, corresponding to a decimal diameter of 0.0098 inches. The 140-degree faceted point geometry with web thinning reduces thrust force and improves centering accuracy at small diameters. A TiAlN coating enhances heat resistance and extends tool life in ferrous materials. The overall length is 38 mm, the spiral flute length is 3 mm, and the straight-cylindrical shank diameter is 3 mm. Cutting direction is right hand. This tool is intended for machinists, toolroom technicians, and precision metalworking shops.

This micro drill bit is suited for small-hole drilling operations in ferrous workpiece materials, specifically cast iron and steel, as indicated by material grade K40 and material codes K and P. Typical applications include component manufacturing, mold and die work, and precision fixture fabrication where tight hole tolerances are required. The h7 shank diameter tolerance and straight-cylindrical shank design allow consistent seating in collet chucks and precision drill chucks. The 5xD flute-to-diameter ratio supports chip evacuation in shallow-depth applications up to a maximum drilling depth of 0.1040 inches (2.63 mm).

Key Features

• Solid carbide construction at material grade K40 for rigidity and wear resistance in ferrous materials
• TiAlN coating for elevated heat resistance during dry and semi-dry cutting
• 140-degree faceted point with web thinning for accurate entry and reduced thrust at 0.0098 inches diameter
• Spiral flute type with regular spiral for consistent chip flow
• Straight-cylindrical shank at 3 mm diameter with h7 tolerance for accurate chuck fitment
• Right-hand cut with 5xD flute ratio supporting shallow-depth precision holes

Compatibility

Designed for use in cast iron and steel workpieces as an OEM-style precision micro drill in Series 3899 applications requiring Wire Gauge 87 diameter holes.

Installation Notes

Installation and use should be performed by qualified machinists or toolroom technicians familiar with micro-diameter tooling. Secure the straight-cylindrical shank firmly in a compatible collet chuck or precision drill chuck rated for the shank diameter before operation. Micro drills are brittle at this diameter — avoid side loading, misalignment, or excessive feed rates that can cause tool breakage. Ensure spindle runout is minimized to protect the tool and maintain hole-location accuracy.