Hertel 77428837 Reduced Shank Drill Bit 57/64 in Hss

Product Description

The HERTEL 77428837 is a reduced shank twist drill bit designed for drilling into low and medium tensile strength materials. It features a 57/64 inch (0.8906 inch decimal) cutting diameter paired with a 1/2 inch Weldon flat shank, allowing it to be chucked in standard 1/2 inch capacity drill presses and milling machines without slippage. The 118-degree standard point angle suits general-purpose drilling in mild steel, aluminum, and similar workpiece materials. At 6 inches overall length with a 3 inch flute length, it handles moderate drilling depths in production and maintenance environments. Licensed HVAC and mechanical technicians, machinists, and maintenance tradespeople are the typical end users.

This bit is suited for shop, field, and production drilling applications where a full-diameter shank would not fit the available chuck. The Weldon flat shank with three flats provides a positive drive connection that resists rotational slippage under cutting load. The oxide finish offers a degree of lubricity and corrosion resistance during storage and use. Typical applications include drilling pilot and clearance holes in structural steel, ductwork, sheet metal assemblies, and similar low-to-medium tensile strength workpieces encountered in HVAC, plumbing, and general mechanical work.

Key Features

• 57/64 inch cutting diameter (0.8906 inch decimal) with reduced 1/2 inch Weldon flat shank for compatibility with standard chucks
• 118-degree standard point angle for general-purpose drilling in mild steel and aluminum
• High-speed steel construction for durability across a range of metal workpieces
• Three-flat Weldon shank design prevents rotational slippage under cutting load
• Oxide finish provides added lubricity and basic corrosion resistance
• Right-hand spiral flute with regular helix for efficient chip evacuation

Compatibility

Designed for use in drill presses, milling machines, and magnetic drills equipped with a 1/2 inch Weldon-style end mill holder or set-screw chuck. Intended for drilling low and medium tensile strength materials per manufacturer specification.

Installation Notes

Secure the Weldon flat shank firmly in the holder set screw before drilling to prevent axial pullout. Ensure the drill press or machine spindle is brought to a full stop before changing or adjusting the bit. Use appropriate cutting fluid or coolant as required by the workpiece material and machine setup, noting this bit does not include internal coolant capability. Inspect the cutting edges for wear or chipping before each use and replace when cutting performance degrades.