Chicago-latrobe 44740 Jobber Drill Bit Size 70 Hss 135

Product Description

The CHICAGO-LATROBE 44740 is a jobber length drill bit in wire gauge size 70, measuring 0.0280 inches in diameter. Built from high speed steel with an oxide coating, this bit is designed for heavy-duty precision drilling in tight-tolerance applications. The 135-degree split point geometry reduces walking on entry and requires no center punch on most workpieces. With a web-thinned, tapered web configuration and regular spiral fluting, it channels chips efficiently and maintains cutting performance through demanding materials. Licensed HVAC techs, machinists, and sheet metal professionals reach for bits like this when hole placement and diameter accuracy are non-negotiable.

This bit is suited for drilling cast iron, stainless steel, and carbon steel in production and maintenance environments. At 1.25 inches overall length with a 0.375-inch flute length, it fits compact drilling situations where longer bits would flex or chatter. The straight-cylindrical shank at 0.0280 inches diameter seats securely in standard drill chucks and collets. The Series 150ASP designation indicates a high-performance tooling line built to NAS 907 Type B standards, making it a reliable choice for aerospace-adjacent and general metalworking applications where dimensional tolerance matters.

Key Features

• Wire gauge size 70, 0.0280-inch diameter with a tight tolerance of -0.0005 to 0.0000 inches
• 135-degree standard point angle reduces drill walk and improves entry accuracy
• High speed steel construction with oxide coating for heat and wear resistance
• Web-thinned tapered web reduces thrust required during cutting
• Right-hand cut, 2-flute regular spiral design promotes efficient chip evacuation
• Meets NAS 907 Type B specification for heavy-duty performance

Compatibility

Designed for use in cast iron, stainless steel, and steel workpieces. Compatible with standard drill chucks and collets accepting a 0.0280-inch straight-cylindrical shank.

Installation Notes

Install and remove drill bits only with the drill or press powered off and the chuck key removed. Secure the workpiece firmly before drilling to prevent movement that can snap small-diameter bits. Use cutting fluid when drilling stainless steel or hardened steel to manage heat and extend bit life. Inspect the cutting edges before each use; a dull or chipped bit at this diameter will wander and produce oversized holes.