Hertel 89321616 Screw Machine Drill Bit 21 Hss 118 Deg

Product Description

The HERTEL 89321616 is a screw machine length drill bit in wire gauge size 21, with a decimal inch diameter of 0.1590 inches. Screw machine length bits are shorter than jobber length drills, providing greater rigidity and reduced deflection in high-cycle production and machine-tool applications. The 118-degree conventional split point is ground from high-speed steel and cuts right-hand. The bright, uncoated finish suits general-purpose drilling in mild steel, aluminum, brass, and similar materials. Overall length is 2.125 inches with a flute length of 1.0625 inches. Machinists, toolroom technicians, and maintenance mechanics install this bit in screw machines, drill presses, and CNC turret lathes.

This bit is rated for general-purpose drilling within the 0.1500 to 0.2000 decimal inch size range. The short overall length makes it well suited for close-tolerance work in screw machine setups, turret lathes, and bench drill presses where a standard jobber drill would introduce excessive runout or chatter. It is appropriate for production shops, MRO maintenance applications, and toolroom use wherever a wire-gauge 21 hole diameter is required in non-hardened work materials.

Key Features

• Wire gauge size 21, 0.1590 inches decimal diameter for precise hole sizing
• 118-degree conventional point angle for general-purpose drilling
• Screw machine length body for maximum rigidity and minimal deflection
• High-speed steel construction suitable for mild steel, aluminum, and non-ferrous metals
• Bright, uncoated finish for general-purpose applications without coating incompatibility concerns
• Right-hand cutting direction, compatible with standard drill press and lathe spindle rotation

Compatibility

Designed as a general-purpose replacement or production-stock screw machine length drill bit for any standard drill press, screw machine, or lathe turret accepting a straight-shank bit of 0.1590 inches diameter.

Installation Notes

A licensed machinist or qualified maintenance technician should secure the bit firmly in a calibrated drill chuck or collet before use, verifying there is no runout before cutting. Ensure the workpiece is clamped or fixtured and the machine is set to an appropriate spindle speed for the work material and bit diameter. Inspect the cutting edges for wear or chipping before each use and replace the bit if the point is dull or damaged. Follow applicable shop safety standards and machine-guarding requirements during all drilling operations.