Kennametal 4150249 Carbide Stub Drill Bit 7.70 Mm

Product Description

The KENNAMETAL 4150249 is a screw machine length (stub) solid carbide drill bit designed for high-performance drilling in demanding production environments. Built to DIN 6537K standards, it features a 140-degree split point for fast penetration and reduced walking on entry. The 7.70 mm cutting diameter is matched to an 8.00 mm straight cylindrical shank, and the multilayer TiAlN coating - applied at the tip - extends tool life in abrasive and moderately heat-intensive materials. With an overall length of 3.1102 inches and a maximum drilling depth of 1.1417 inches, this bit is suited for close-tolerance production work where rigidity and repeatability matter.

This drill bit is intended for use in CNC machining centers, drill presses, and screw machines where stub-length tools are preferred for improved stiffness and reduced deflection. It is well suited for drilling steel, cast iron, and similar ferrous workpiece materials in job shop and production machining settings. The right-hand cutting direction and regular spiral flute geometry support efficient chip evacuation in typical through-hole and blind-hole applications. A licensed machinist or CNC operator is the typical end user.

Key Features

• Solid carbide construction for rigidity and wear resistance in production drilling
• 140-degree drill point angle reduces thrust and minimizes workpiece burring on breakthrough
• TiAlN (TiN tip) multilayer coating improves heat resistance and extends edge life
• Stub length (screw machine length) design increases rigidity and reduces deflection versus jobber-length bits
• Straight cylindrical shank with 8.00 mm diameter fits standard toolholders and drill chucks
• DIN 6537K specification compliance supports interchangeability in metric tooling setups

Compatibility

Designed as an OEM-style replacement or production-use drill bit for CNC machining centers, turret lathes, and screw machines requiring a stub-length solid carbide bit in the 7.70 mm diameter class. Belongs to KENNAMETAL Series B041A-CPG.

Installation Notes

Installation is performed by a qualified machinist or CNC setup technician. Ensure the machine spindle is fully stopped and the toolholder is clean and free of debris before seating the shank. Verify runout at the cutting edge after installation using a dial test indicator - excessive runout accelerates carbide wear and can cause premature breakage. Follow the machine manufacturer and ANSI B11 safety guidelines for tooling installation and drill press or CNC operation.