Chicago-latrobe 48420 Screw Machine Drill Bit 0.07 in Hss

Product Description

The CHICAGO-LATROBE 48420 is a screw machine length drill bit designed for high-production drilling in metalworking applications. Built from high speed steel (HSS) with a coated finish, this bit features a 135-degree split point and a web-thinned, parallel web configuration that reduces thrust and improves centering on entry. At 0.07 inches in diameter (Wire Size 50), the 48420 is suited for close-tolerance work where diameter consistency matters. The straight-cylindrical shank fits standard drill chucks, and the two-flute spiral design evacuates chips efficiently during operation. Overall length is 1-11/16 inches with a flute length of 11/16 inches, keeping the bit rigid and minimizing deflection in short-reach setups.

This bit is intended for heavy-duty drilling in cast iron and steel workpieces. The screw machine length format — shorter than jobber length — makes it the preferred choice in drill presses, CNC turret lathes, screw machines, and multi-spindle setups where rigidity and repeatability are critical. The right-hand cut spiral flute configuration is standard for conventional drilling operations. Manufactured to NAS 907 and ISO standards, the 48420 is appropriate for production shops, machine shops, and maintenance environments requiring consistent, repeatable small-diameter hole quality.

Key Features

• Wire Size 50 (0.0700 inches) diameter with tight tolerance of +0.0000 to -0.0005 inches
• 135-degree split point reduces walking and lowers required thrust force
• Web-thinned parallel web for easier penetration in hard ferrous materials
• High speed steel construction with coated finish for extended tool life
• Screw machine length (1-11/16 inches overall) maximizes rigidity and minimizes deflection
• Manufactured to NAS 907 and ISO standards for production-grade consistency

Compatibility

Designed for drilling cast iron and steel workpieces. Compatible with any standard drill chuck accepting a straight-cylindrical shank. Intended for use in drill presses, screw machines, turret lathes, and CNC equipment requiring Wire Size 50 tooling.

Installation Notes

Install and remove drill bits only with the spindle fully stopped and the machine isolated from power. Secure the straight-cylindrical shank firmly in the chuck and verify runout before production drilling. Use appropriate cutting fluid or coolant for steel workpieces to extend bit life, noting this bit does not support coolant-through delivery. Follow shop safety practices and applicable OSHA machining guidelines when operating rotating tooling.