Hertel 77429009 Reduced Shank Drill Bit 1-3/16 in Hss

Product Description

The HERTEL 77429009 is a reduced shank twist drill bit designed for drilling into low and medium tensile strength materials. It features a 1-3/16 inch cutting diameter paired with a 1/2 inch Weldon flat shank, allowing it to seat securely in standard chucks and holders without slipping under torque. The bit is manufactured from high-speed steel with an oxide finish that provides basic corrosion resistance and reduces friction during cutting. A 118-degree standard point angle makes it suitable for general-purpose drilling across a wide range of common workpiece materials. Licensed machinists, maintenance technicians, and industrial tradespeople are the primary installers and users of this bit.

This bit is suited for production and maintenance drilling applications in shops, mechanical rooms, and field settings where a reduced shank profile is needed to fit standard 1/2 inch capacity chucks while still cutting a 1-3/16 inch hole. Its 3 inch flute length supports drilling to a maximum depth of 3 inches per pass. The right-hand spiral flute geometry evacuates chips efficiently during through-hole and blind-hole operations in mild steel, aluminum, copper, and similar low to medium tensile strength materials.

Key Features

• 1-3/16 inch cutting diameter with a reduced 1/2 inch Weldon flat shank for compatibility with standard chucks
• High-speed steel construction handles moderate cutting speeds and general-purpose drilling duties
• 118-degree standard point angle for reliable starting and clean entry on flat and curved surfaces
• Oxide finish reduces surface friction and provides light corrosion resistance
• 3-flute Weldon flat shank with 3 flats prevents bit rotation in the chuck under load
• Right-hand spiral flute geometry promotes consistent chip evacuation up to 3 inches drilling depth

Compatibility

Designed for use in 1/2 inch capacity drill chucks and Weldon-style tool holders. Suitable for drilling low and medium tensile strength materials including mild steel, aluminum, and similar metals.

Installation Notes

Secure the Weldon flat shank fully in a matched chuck or holder, tightening set screws against the flats to prevent rotation under load. Always power down and lock out the machine before changing bits. Use cutting fluid appropriate to the workpiece material to extend bit life and improve surface finish, though this bit is rated for dry cutting. Inspect the cutting edges for wear before each use and replace when the point shows chipping or heat discoloration.