Chicago-latrobe 48390 Screw Machine Drill Bit 0.161 in

Product Description

The CHICAGO-LATROBE 48390 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, this bit delivers consistent performance in demanding shop and field applications. The 135-degree split point reduces walking and penetrates work materials faster than a standard 118-degree point. At 2.125 inches overall length, the shortened screw machine geometry provides added rigidity and is well suited for use in turret lathes, screw machines, and CNC drilling operations where close-tolerance holes are required.

This bit is sized at 0.161 inches in diameter, corresponding to wire gauge size 20. It is intended for drilling cast iron and steel in industrial manufacturing, maintenance, and fabrication environments. The heavy-duty Series 2159 designation indicates construction suited for repetitive cycling in production equipment. The parallel web configuration and web-thinned geometry reduce thrust requirements and extend tool life during high-volume runs. Licensed machinists, tool-and-die technicians, and maintenance mechanics are the primary installers and users of this tool.

Key Features

• 135-degree split point for fast penetration and reduced walking on entry
• Web-thinned, parallel web design reduces drilling thrust and heat buildup
• High speed steel construction with coated finish for extended wear resistance
• Screw machine length body adds rigidity over jobber-length bits in fixed tooling setups
• Right-hand cut with regular spiral flute for efficient chip evacuation
• Meets NAS 907 specification under NAS designation for dimensional conformance

Compatibility

Designed as a replacement or production-use screw machine length drill bit for drilling cast iron and steel workpieces. Fits standard straight-cylindrical shank drill chucks and collet holders accepting 0.161-inch shank diameter tooling.

Installation Notes

This bit is installed into a drill chuck or collet holder by a machinist or maintenance technician. Ensure the machine spindle is fully stopped and locked out before changing tooling. Verify chuck or collet bore is clean and undamaged before seating the shank. Do not exceed the spindle speed and feed rate recommendations for the workpiece material and bit diameter.