Chicago-latrobe 48234 Drill Bit Letter B 0.2380 in Hss

Product Description

The CHICAGO-LATROBE 48234 is a screw machine length drill bit designed for heavy-duty drilling in cast iron and steel. It carries a Letter B diameter of 0.2380 inches and features a 135-degree split point that reduces walking at the start of a cut and lowers the thrust required to penetrate hard materials. The flutes are spiral-cut in a regular helix with web thinning applied for improved chip evacuation. The high-speed steel construction with a coated finish provides wear resistance under sustained production use. At 2.5 inches overall length, this stub-style bit fits tight-clearance applications where a jobber-length bit would foul on the workpiece or fixture.

This bit is suited for machining and fabrication environments where screw machine length geometry is specified. Typical applications include CNC screw machine operations, drill press work, and hand-held drilling in ferrous metals such as carbon steel and cast iron. The straight-cylindrical shank seats in standard drill chucks without requiring a Morse taper adapter. Series 2159 construction meets NAS 907 and ISO standards, making it appropriate for aerospace-adjacent and precision manufacturing applications where dimensional tolerances must be held tight.

Key Features

• Letter B diameter, 0.2380 inches, tolerance +0.0000 to -0.0007 inches
• 135-degree split point reduces thrust and eliminates center-punch requirement on most setups
• Screw machine (stub) length at 2.5 inches OAL improves rigidity and reduces deflection
• Web-thinned parallel web for faster chip clearance in deep holes
• High-speed steel with coated finish for extended tool life in ferrous materials
• Right-hand cut, 2-flute spiral design, straight-cylindrical shank for universal chuck compatibility
• Meets NAS 907 and ISO specifications

Compatibility

Designed for drilling cast iron and steel workpieces. Straight-cylindrical shank at 0.2380 inches diameter fits standard 3-jaw drill chucks on drill presses, CNC screw machines, and hand-held power drills accepting the Letter B size range.

Installation Notes

Installation and use of this bit should be performed by machinists or qualified trades personnel familiar with metalworking drill practices. Secure the shank fully in the chuck before operation and verify runout is within acceptable limits for the application. Always wear appropriate eye protection and ensure the workpiece is clamped or fixtured before drilling. Do not exceed the recommended speed and feed parameters for the workpiece material and bit diameter.