Chicago-latrobe 48728 Screw Machine Drill Bit Hss

Product Description

The CHICAGO-LATROBE 48728 is a screw machine length drill bit designed for high-speed steel cutting in general-purpose metalworking applications. It features a 0.1405-inch diameter corresponding to wire size 28, a 118-degree standard point angle, and a bright uncoated finish. The overall length is 1-15/16 inches with a 15/16-inch flute length, making it shorter and more rigid than jobber-length bits. Two spiral flutes with a right-hand cut and a straight cylindrical shank are standard. Web thinning reduces entry resistance in harder materials. This bit is well suited for machinists, tool-and-die tradespeople, and maintenance mechanics working on production or repair drilling tasks.

This drill bit is intended for drilling cast iron, non-ferrous metals, and steel in screw machine, lathe, and drill press setups where a shorter, stiffer bit is preferred over a jobber-length tool. The reduced length improves rigidity and helps maintain hole location accuracy in production environments. It belongs to CHICAGO-LATROBE Series 157, a general-purpose high speed steel line built to ISO standards. Typical users include machinist shops, industrial maintenance departments, and metal fabrication operations requiring consistent small-diameter hole quality.

Key Features

• Wire size 28 diameter at 0.1405 inches with a tight tolerance of +0.0000 to -0.0007 inches
• Screw machine length body for added rigidity and reduced deflection compared to jobber-length bits
• 118-degree standard point angle with web thinning for reduced entry thrust
• Two spiral flutes in a regular helix configuration for efficient chip evacuation
• Bright uncoated high speed steel construction suited for general-purpose metalworking
• Right-hand cut with a straight cylindrical shank for compatibility with standard drill chucks

Compatibility

Designed for use in standard drill chucks and screw machine setups that accept straight cylindrical shanks. Primary workpiece materials include cast iron, non-ferrous metals, and steel. Part of the CHICAGO-LATROBE Series 157 general-purpose drill bit line built to ISO standards.

Installation Notes

This bit is installed and operated by machinists and maintenance mechanics using drill presses, screw machines, lathes, or hand-held power drills. Secure the straight shank firmly in a drill chuck before operation and verify the spindle is stopped before changing bits. Use appropriate cutting fluid when drilling steel or cast iron to extend tool life and improve hole finish. Inspect the cutting edges before each use and replace if chipping or wear is visible to maintain hole tolerance.