Osg 61540 Screw Machine Drill Bit 0.1575 in Hss

Product Description

The OSG 61540 is a screw machine length drill bit designed for high-performance drilling in metalworking and machining applications. Built from high speed steel (HSS) with a coated finish, it measures 4.00 mm (0.1575 inches) in diameter with a 130-degree faceted point angle optimized for fast, accurate entry. The web-thinned, tapered web design reduces thrust and improves chip evacuation. With two spiral flutes and a straight-cylindrical shank, this bit is suited for use in CNC machining centers, drill presses, and screw machine operations where compact stub-length tooling is required. Installation and operation are typically performed by machinists and toolroom professionals.

This bit is rated for drilling steel, stainless steel, aluminum, aluminum alloy, and aluminum silicate workpiece materials, covering a broad range of common shop applications. The screw machine (stub) length format provides increased rigidity over jobber-length bits, making it well suited for close-tolerance hole-making in production environments. It falls within the 0.1500 to 0.2000 inch drill size range, fitting standard drill chucks and collet systems that accept 4.00 mm straight-cylindrical shanks. The Series 1100 designation identifies the OSG product family for this geometry and performance tier.

Key Features

• 4.00 mm (0.1575 inch) diameter with diameter tolerance of +0 to -0.018 mm for close-tolerance work
• 130-degree faceted point angle with web thinning for reduced entry thrust and improved chip flow
• High speed steel construction with coated finish for extended tool life in ferrous and non-ferrous materials
• Screw machine (stub) length format provides greater rigidity than jobber-length equivalents
• Two spiral flutes with regular spiral and 5xD flute-to-diameter ratio for efficient chip evacuation
• Right-hand cut with straight-cylindrical shank compatible with standard chucks and collet systems

Compatibility

Designed for drilling steel, stainless steel, aluminum, aluminum alloy, and aluminum silicate. Fits standard drill chucks and collet holders accepting a 4.00 mm straight-cylindrical shank. Suitable for use across the 0.1500 to 0.2000 inch drill size range applications in OSG Series 1100 tooling setups.

Installation Notes

Installation and tool changes should be performed by a qualified machinist with the machine powered down and locked out before securing or removing the bit. Ensure the chuck or collet is properly tightened to the shank before operating. Coolant-through is not supported on this bit; external coolant or cutting fluid application is recommended when drilling stainless steel or other difficult materials to manage heat buildup. Follow the machine manufacturer guidelines and applicable shop safety standards for feed rate and spindle speed selection based on workpiece material.