Hertel 77428621 Reduced Shank Drill Bit 37/64 in Hss

Product Description

The HERTEL 77428621 is a reduced shank twist drill bit designed for metal drilling operations in light industrial and maintenance environments. The bit features a 37/64 inch (0.5781 inch decimal) cutting diameter paired with a 1/2 inch Weldon flat shank, allowing use in standard 1/2 inch chuck machines while delivering a larger bore diameter. Built from high-speed steel with an oxide finish, the 77428621 carries a 118-degree standard point angle suited for general-purpose drilling into low and medium tensile strength materials. Overall length is 6 inches with a 3 inch flute length. Right-hand spiral flutes clear chips efficiently during through-hole and blind-hole applications.

This drill bit is intended for machinists, tool-and-die technicians, maintenance mechanics, and metalworking professionals drilling into low and medium tensile strength materials such as mild steel, aluminum, and similar workpiece stock. The Weldon flat shank prevents slipping in milling-style tool holders and set-screw chuck configurations. The reduced shank design makes this bit practical when a larger bore is needed but machine spindle capacity is limited to 1/2 inch shank tooling. Typical applications include production drilling, fixture work, and general shop use on manual or CNC drill press equipment.

Key Features

• 37/64 inch cutting diameter with 0.5781 inch decimal equivalent for precise bore sizing
• 1/2 inch Weldon flat shank with 3 flats prevents rotation in set-screw tool holders
• 118-degree standard point angle for general-purpose entry into low and medium tensile strength metals
• High-speed steel construction provides durability across repeated drilling cycles
• Oxide finish reduces friction and provides baseline corrosion resistance
• Right-hand cut with regular spiral flutes for efficient chip evacuation

Compatibility

Designed as a general-purpose reduced shank drill bit compatible with 1/2 inch Weldon flat tool holders, set-screw drill chucks, and milling machine spindles accepting 1/2 inch shank tooling.

Installation Notes

Installation should be performed by a qualified machinist or maintenance mechanic. Secure the Weldon flat shank fully into the tool holder and tighten the set screw against the flat before operation. Ensure the drill press or milling machine spindle is fully stopped and locked out before changing tooling. Do not exceed the rated drilling depth of 3 inches or use this bit on materials beyond its rated tensile strength range without verifying suitability.