Guhring 9038990003300 Micro Drill Bit No. 81 Solid Carbide

Product Description

The GUHRING 9038990003300 is a solid carbide micro drill bit designed for precision drilling in demanding metal-cutting applications. Ground to a 140-degree faceted point with web thinning, it produces clean entry geometry and reduces thrust in hard materials. The TiAlN coating improves heat resistance and extends tool life in ferrous materials. At 38 mm overall length with a 5 mm flute length and a maximum drilling depth of 4.51 mm, this bit is built for tight-tolerance, small-diameter work. The straight-cylindrical shank measures 3 mm in diameter, and the bit diameter tolerance is held to h7 for consistent fit in collet-style toolholding. Installed by machinists and tool-and-die professionals in CNC and manual drilling operations.

This micro drill bit is sized to wire gauge No. 81, equivalent to 0.0130 inches in decimal, making it appropriate for fine pilot holes, through-holes in castings, and precision drilling in cast iron and steel workpieces. The spiral flute with a regular spiral type and a 5xD flute-to-diameter ratio provides efficient chip evacuation in short, shallow holes. Series 3899 from GUHRING is engineered for small-diameter solid carbide tooling where dimensional accuracy and coating durability are critical. Typical applications include component manufacturing, mold and die work, and precision fabrication shops running cast iron or steel stock.

Key Features

• Solid carbide construction in material grade K40 for rigidity and wear resistance in hard workpiece materials
• TiAlN coating for elevated heat resistance and extended tool life in steel and cast iron
• 140-degree faceted point geometry with web thinning to reduce entry thrust and improve hole entry accuracy
• Straight-cylindrical 3 mm shank with h7 diameter tolerance for precise collet fitment
• 5xD flute-to-diameter ratio spiral flute for effective chip removal in shallow-depth drilling
• Right-hand cut with regular spiral type for standard CNC and manual drill press spindle rotation

Compatibility

Designed for use in cast iron and steel workpieces as noted by primary workpiece material codes K and P. Fits standard 3 mm collet toolholders. No coolant-through capability; external coolant or mist lubrication applies where required by the application.

Installation Notes

This tool is installed by machinists in CNC machining centers, drill presses, or manual milling machines using a collet or chuck sized for a 3 mm straight shank. Secure the shank to the full recommended grip depth before running the spindle. Because this bit has no coolant-through capability, apply external cutting fluid or mist coolant appropriate for the workpiece material to manage heat and chip evacuation. Inspect the cutting edges under magnification before each use, as solid carbide micro drills are brittle and susceptible to chipping if the point is damaged or the setup introduces runout.