Chicago-latrobe 48211 Screw Machine Drill Bit 11/64 Hss

Product Description

The CHICAGO-LATROBE 48211 is a screw machine length drill bit designed for high-production drilling in cast iron and steel. Built from high speed steel with a coated finish, it offers a 135-degree split point and web-thinned geometry that reduces thrust and improves centering without a separate punch or pilot. The straight-cylindrical shank fits standard drill chucks. At 0.1719 inches (11/64) in diameter and 2.125 inches overall length, this is a compact, stub-style bit sized for close-quarter or machine-mounted applications where a jobber-length bit would chatter or flex. The Series 2159 designation indicates a heavy-duty performance tier with parallel web configuration and regular spiral fluting.

This bit is suited for production machining environments, CNC drill presses, and manual drilling operations on ferrous materials including cast iron and steel. The screw machine length keeps the tool rigid under repeated cycling, making it a common choice for automated or high-cycle manual drilling fixtures. The 135-degree split point geometry eliminates walking on flat surfaces, reducing setup time in production lines. This bit conforms to NAS 907 specification under NAS standards, positioning it for aerospace-adjacent and precision industrial applications where dimensional compliance is required.

Key Features

• 135-degree split point with web thinning for reduced thrust and self-centering entry
• High speed steel construction with coated finish for wear resistance on ferrous materials
• Screw machine (stub) length provides added rigidity versus jobber-length bits
• Right-hand cut with regular spiral fluting for efficient chip evacuation
• Straight-cylindrical shank fits standard drill chucks without adapters
• Meets NAS 907 specification for dimensional and performance compliance

Compatibility

Designed for drilling cast iron and steel workpieces. Primary workpiece materials per specification are cast iron and steel. Compatible with any drill press, CNC machining center, or hand drill fitted with a standard straight-shank chuck sized to accept a 0.1719-inch shank.

Installation Notes

Installation of this drill bit is performed by machinists and maintenance technicians using any drill press or power drill with a compatible straight-shank chuck. Secure the shank fully in the chuck and verify runout before beginning a production run. Use appropriate cutting fluid or coolant as required by the base material to preserve bit life, noting that this bit does not support coolant-through delivery. Inspect the cutting edges for wear or chipping after extended use on hardened or abrasive materials.