Kennametal 4150239 Stub Drill Bit 6.90mm Carbide Tialn

Product Description

The KENNAMETAL 4150239 is a stub-length (screw machine length) drill bit engineered for high-performance drilling in metal, alloy, and hard-material applications. Built from solid carbide and finished with a multilayer TiAlN coating at the tip, this bit delivers elevated wear resistance and thermal stability compared to HSS alternatives. The 140-degree split point reduces thrust and improves centering without a pilot hole. At 3.1102 inches overall length with a 1.3386-inch flute, it is designed for use in CNC machining centers, drill presses, and screw machines where rigidity and tight-tolerance hole quality are required. Installation is performed by machinists and CNC operators working to DIN 6537K standards.

This drill bit is suited for production drilling environments requiring consistent hole diameter within a tight tolerance band. Its stub-length geometry provides added rigidity over jobber-length bits, reducing deflection in short-to-medium depth holes. The straight cylindrical shank at 8.00 mm diameter fits standard collet chucks and drill chucks. Maximum drilling depth is 24.00 mm (0.9449 inches), making it appropriate for through-holes and blind holes in workpieces where depth-to-diameter ratio does not exceed approximately 3xD. It performs reliably in both dry and light-lubricant drilling setups where coolant-through capability is not required.

Key Features

• Solid carbide construction for superior hardness and wear resistance over HSS or cobalt alternatives
• TiAlN tip coating improves thermal resistance and extends tool life at elevated cutting speeds
• 140-degree point angle reduces entry thrust and self-centers on flat or curved surfaces
• Stub-length body (79.00 mm OAL) maximizes rigidity and minimizes deflection
• Right-hand, regular spiral flute with tapered web for efficient chip evacuation
• Manufactured to DIN 6537K specification for consistent dimensional tolerance

Compatibility

Designed for use in standard collet chucks or drill chucks accepting an 8.00 mm straight cylindrical shank. Part of the KENNAMETAL B041A-CPG series, covering drill diameters in the 6.50 mm to 8.00 mm range (0.2500 to 0.3000 decimal inch).

Installation Notes

This bit is installed by machinists and CNC operators into compatible toolholding systems; verify chuck or collet bore matches the 8.00 mm shank diameter before seating. Power down and lockout the spindle before changing tooling. Do not exceed the 24.00 mm maximum drilling depth rating. Confirm cutting parameters (speed and feed) are appropriate for solid carbide tooling in the workpiece material to avoid tip fracture.