Chicago-latrobe 41796 Drill Bit Letter Z 135 Hss Tin

Product Description

The CHICAGO-LATROBE 41796 is a jobber-length twist drill bit sized to Letter Z (0.4130 inches decimal equivalent), designed for heavy-duty metalworking applications. It is manufactured from high-speed steel and finished with a titanium nitride (TiN) coating to extend tool life and reduce heat buildup during cutting. The bit features a 135-degree split point for fast penetration and reduced walking on entry, a web-thinned, tapered web configuration, and a right-hand spiral flute. Overall length is 5.25 inches with a flute length of 3.875 inches. The straight-cylindrical shank measures 1.375 inches, making it compatible with standard drill chucks. This bit meets NAS 907 Type B specifications and is part of the Series 150ASP-TN.

This drill bit is built for professional use on ferrous and hard-to-machine materials including cast iron, stainless steel, and carbon steel. The TiN coating provides a hard, low-friction surface that is particularly effective when drilling stainless steel, where heat management is critical. It is suited for production and maintenance drilling in industrial, fabrication, and shop environments. The 2-flute regular spiral design maintains chip clearance and cutting efficiency across a range of feed rates and spindle speeds appropriate for the 0.4000 to 0.5000 inch diameter range.

Key Features

• Letter Z size — 0.4130 inches decimal equivalent for precise bore sizing
• 135-degree split point reduces thrust and eliminates center-punching on most metals
• Titanium nitride (TiN) coating improves wear resistance and lubricity
• Web-thinned, tapered web construction lowers cutting resistance in tough alloys
• Meets NAS 907 Type B specification for controlled dimensional tolerances
• Right-hand, 2-flute regular spiral for reliable chip evacuation

Compatibility

Designed for use on cast iron, stainless steel, and steel workpieces. Fits standard drill chucks accepting a straight-cylindrical shank. Suitable for drill presses, CNC drilling centers, and hand-held drill applications within the 0.4000 to 0.5000 inch diameter class.

Installation Notes

This bit is installed and operated by machinists, tool-and-die technicians, and maintenance mechanics. Secure the straight shank fully in a properly sized chuck before operation. Use appropriate cutting fluid or coolant when drilling stainless steel or cast iron to extend bit life and maintain hole quality. Inspect the cutting edges and TiN coating before each use and replace the bit if chipping or coating wear is visible.