Kennametal 1957789 Screw Machine Drill Bit 5.90mm Carbide

Product Description

The KENNAMETAL 1957789 is a screw machine length drill bit engineered for demanding metal-removal applications in production and maintenance environments. Built from solid carbide in the KC7315 material grade and coated with TiAlN for heat and wear resistance, this bit delivers consistent performance in cast iron and steel. The 140-degree split point reduces thrust and improves centering without a center punch. Overall length is 2.598 inches (66.00 mm) with a 5.90 mm cutting diameter, making it compact enough for tight-access drilling on screw machines, CNC lathes, and machining centers. Installed by machinists and tool-and-die professionals in high-cycle production settings.

This drill bit is designed for short-hole drilling in cast iron and steel workpieces, with a maximum drilling depth of 20.00 mm. The B966A series follows DIN 6537K geometry standards, which specifies screw machine (stub) length proportions for rigidity and reduced deflection in high-feed applications. The straight cylindrical shank at 6.00 mm diameter fits standard collet chucks and tool holders common to CNC turning and milling setups. Web-thinned geometry reduces cutting forces and improves chip evacuation on entry. This bit is suited for both job shop and automated line use where repeatable hole quality in ferrous materials is required.

Key Features

• Solid carbide KC7315 grade construction for extended tool life in ferrous materials
• TiAlN coating improves heat resistance and reduces built-up edge at elevated cutting speeds
• 140-degree standard point angle with web thinning reduces thrust and improves self-centering
• DIN 6537K specification geometry ensures consistent screw machine length proportions
• Two-flute regular spiral design promotes chip clearance in through and blind holes up to 20.00 mm deep
• Drill bit diameter tolerance of +0.004 to +0.016 mm supports close-tolerance hole sizing

Compatibility

Designed for use in cast iron and steel workpieces. Compatible with standard collet chucks and tool holders accepting a 6.00 mm straight cylindrical shank. Fits screw machines, CNC lathes, and machining centers equipped for stub-length carbide tooling in the 5.00 mm to 6.50 mm diameter range.

Installation Notes

Installation and tool changes should be performed with the machine in a fully stopped and locked-out state per applicable machine guarding and lockout/tagout procedures. Seat the straight shank fully into the collet or tool holder and verify runout before initiating a cut. Carbide tooling is brittle and should not be used in hand-held or unsupported drilling setups. Inspect the cutting edges and coating condition before each production run to avoid premature hole-quality degradation.