Osg HP243-2969 Screw Machine Drill Bit 19/64 in Carbide

Product Description

The OSG HP243-2969 is a screw machine length drill bit designed for high-performance drilling in steel, alloy steel, and cast iron. It carries a 19/64-inch (0.2969 inch decimal) diameter with a 140-degree point angle and an R-thinned point geometry that reduces thrust and improves chip evacuation at entry. The bit is ground from solid carbide and finished with OSG EgiAs coating for extended tool life in demanding production environments. Overall length is 3.11 inches (79 mm) with a flute length of 1.61 inches (41 mm). The shorter screw machine length profile offers increased rigidity compared to jobber-length bits, making it well suited for close-tolerance holes in tough materials.

This drill bit is intended for use in CNC machining centers, turret lathes, and screw machine applications where rigidity and hole accuracy are priorities. The straight-cylindrical shank measures 0.3150 inch (8.00 mm) in diameter and fits standard collets and chucks used in production shops and toolrooms. The 3xD flute-to-diameter ratio and tapered web configuration support chip flow in through-hole and blind-hole operations on steel and ferrous cast materials. It is typically purchased by machinists, tool-and-die shops, and production facilities running high-volume drilling cycles.

Key Features

• Solid carbide construction for rigidity and wear resistance in ferrous materials
• EgiAs coating reduces friction and extends cutting edge life in steel and alloy steel
• 140-degree point angle with R-thinned web minimizes entry thrust and walking
• Screw machine length (3.11 inches OAL) provides enhanced rigidity over jobber-length alternatives
• Right-hand spiral flute with tapered web configuration promotes chip evacuation
• Drill bit diameter tolerance of +0.006 to +0.021 mm supports close-tolerance hole requirements

Compatibility

Primary workpiece materials are steel, alloy steel, and cast iron. Compatible with standard straight-bore collets and drill chucks accepting an 8.00 mm (0.3150 inch) shank. Part of the OSG HP243 series covering the 0.2500 to 0.3000 inch decimal diameter range.

Installation Notes

Installation and use of this tool should be performed by qualified machinists familiar with carbide tooling. Secure the shank fully in a collet or drill chuck to the manufacturer-recommended engagement depth before running spindle power. Carbide tooling is brittle — avoid side loads, interrupted cuts without proper feed-rate adjustment, and re-chucking a hot bit without allowing it to cool. Follow your machine tool manufacturer guidelines and applicable shop safety protocols when setting speeds and feeds for carbide drills in ferrous materials.