Guhring 9038990014000 Micro Drill Bit 1.40mm 140pt Carbide

Product Description

The GUHRING 9038990014000 is a solid carbide micro drill bit designed for precision drilling in demanding industrial and machining applications. Built to Series 3899 standards, it features a 140-degree faceted point angle and a TiAlN coating that resists heat and wear during high-speed cutting. The bit measures 1.40mm in diameter (wire size 54, 0.0551 decimal inch) with an overall length of 38.00mm and a flute length of 10.00mm. Web-thinned geometry reduces thrust and improves chip evacuation at entry. The straight-cylindrical shank measures 3.00mm in diameter and seats securely in standard collet chucks or drill chucks. This bit is installed by machinists, toolmakers, and CNC operators working with tight-tolerance small-diameter holes.

This micro drill bit is suited for precision drilling in cast iron and steel workpieces, covering primary material codes K and P. The 5xD flute-to-diameter ratio supports drilling to a maximum depth of 7.90mm (0.311 inch). The regular spiral flute with right-hand cut directs chips upward and out of the hole. Applications include component manufacturing, mold and die work, and CNC machining centers where small-diameter, close-tolerance bores are required. The h7 shank diameter tolerance ensures consistent runout when seated in precision toolholders.

Key Features

• Solid carbide construction in material grade K40 for hardness and wear resistance
• TiAlN coating extends tool life in ferrous materials including cast iron and steel
• 140-degree faceted point angle reduces walking and improves entry accuracy
• Web-thinned geometry lowers thrust force and enhances chip flow
• Straight-cylindrical shank with h7 tolerance for precise collet or chuck fitment
• Right-hand spiral flute with 5xD ratio supports depths up to 7.90mm

Compatibility

Designed as a Series 3899 OEM-style micro drill bit for precision machining in cast iron and steel. Suitable for use in CNC machining centers, drill presses, and manual machines equipped with collet chucks or drill chucks accepting a 3.00mm straight-cylindrical shank.

Installation Notes

This bit is installed by machinists or CNC operators; power down or disable the spindle before changing tooling. Secure the shank fully within the collet or chuck to the recommended grip depth to minimize runout. Micro drills are brittle — avoid side loading, pecking beyond manufacturer cycle recommendations, or applying hand pressure to redirect the spindle. Follow applicable machine guarding and PPE requirements per shop safety standards.