Chicago-latrobe 45678 Jobber Drill Bit 8 Wire Hss 135

Product Description

The CHICAGO-LATROBE 45678 is a jobber-length drill bit in wire gauge size 8, equivalent to 0.1990 inches in decimal, designed for production and maintenance drilling in demanding materials. Built from high-speed steel with an oxide finish, it runs a 135-degree split-point tip that reduces walking on entry and lowers the thrust needed to start the cut. The tapered web and web-thinned geometry keep the cutting edge aggressive through the full depth of the hole. At 3.625 inches overall length with a 2.4375-inch flute, this bit fits standard drill chucks and magnetic drill presses used daily in metal fabrication and mechanical contracting shops.

This bit is suited for right-hand drilling into cast iron, stainless steel, and carbon steel in both shop and field environments. The straight cylindrical shank seats securely in keyless or keyed Jacobs-style chucks. The two-flute spiral design with regular helix clears chips efficiently in through-hole and blind-hole operations. It meets NAS 907 Type B specification, making it appropriate for aerospace-adjacent maintenance work and heavy-duty industrial applications where dimensional tolerances and bit grade matter. Installers in mechanical, structural steel, and HVAC fabrication trades will find it a reliable everyday choice for ferrous metal drilling.

Key Features

• Wire gauge size 8 (0.1990 inches) with a diameter tolerance of -0.0007 to 0.0000 inches for consistent hole size
• 135-degree split point reduces center-walking and lowers feed pressure on hard materials
• High-speed steel construction with oxide coating for corrosion resistance and reduced friction
• Web-thinned, tapered web geometry improves chip clearance and cutting efficiency
• Straight cylindrical shank (0.1990 inches diameter) fits standard drill chucks without adapters
• NAS 907 Type B compliant, heavy-duty grade rated for cast iron, stainless steel, and steel

Compatibility

Designed for use in standard 3-jaw drill chucks accepting straight cylindrical shanks. Primary workpiece materials listed by the manufacturer are cast iron, stainless steel, and carbon steel. Series 150ASP heavy-duty jobber-length format is a common replacement for worn or broken wire gauge 8 HSS bits in industrial and trade-shop drill inventories.

Installation Notes

This bit is installed by licensed machinists, millwrights, ironworkers, HVAC fabricators, and maintenance mechanics. Secure the straight shank fully into the chuck before operation and confirm zero runout before cutting into stainless steel or cast iron to prevent premature dulling. Use cutting fluid or coolant rated for the workpiece material when drilling stainless steel to manage heat buildup. Inspect the split point for chipping after heavy use, as a damaged tip will increase thrust load and reduce hole quality.