Guhring 9038990008900 Micro Drill Bit No. 65 Solid Carbide

Product Description

The GUHRING 9038990008900 is a solid carbide micro drill bit designed for precision drilling in demanding metalworking applications. Sized at wire gauge No. 65 (0.0350 inches in diameter), it features a 140-degree faceted point angle and a TiAlN coating that extends tool life in high-heat cutting environments. The bit measures 38 millimeters in overall length with a 10-millimeter flute length and is web-thinned to reduce thrust and improve chip evacuation. A straight-cylindrical shank with a 3-millimeter diameter ensures secure chuck engagement. This tool is installed and used by machinists, tool-and-die makers, and precision fabricators working with tight-tolerance bore requirements.

This micro drill bit is suited for drilling cast iron and steel in applications where small-diameter, high-accuracy holes are required. The 5xD flute-to-diameter ratio supports controlled chip flow in shallow-to-moderate depth holes, with a maximum drilling depth of 8.67 millimeters (0.3410 inches). Right-hand spiral flutes and a regular spiral type make this bit compatible with standard CNC machining centers, drill presses, and precision hand equipment configured for right-hand rotation. Series 3899 is Guhring's micro-drill line targeting close-tolerance work in production and tool room environments.

Key Features

• Wire gauge No. 65 diameter — 0.0350 inches — for micro-precision bore work
• 140-degree faceted point with web thinning reduces entry thrust and improves centering
• TiAlN coating increases heat resistance and extends tool life in ferrous materials
• Solid carbide construction in K40 material grade for rigidity and wear resistance
• Straight-cylindrical shank, 3 millimeters in diameter, fits standard collets and chucks
• Right-hand cut, regular spiral flute with h7 diameter tolerance for repeatable results

Compatibility

Designed for use in cast iron and steel workpieces as noted by primary workpiece material codes K and P. Compatible with standard right-hand rotation spindles accepting a 3-millimeter straight-cylindrical shank.

Installation Notes

This drill bit is installed by machinists and CNC operators; ensure the spindle and all motion axes are fully stopped and locked out before changing tooling. Seat the shank fully in a collet or drill chuck rated for the shank diameter to prevent runout at micro-drill diameters. Do not exceed the recommended maximum drilling depth of 8.67 millimeters without retracting to clear chips. Coolant-through is not supported on this bit, so apply external coolant or cutting fluid appropriate for the workpiece material.