Hertel 89321079 Screw Machine Drill Bit Letter M Hss

Product Description

The HERTEL 89321079 is a screw machine length drill bit sized to Letter M (0.2950 inches decimal equivalent) and built from high-speed steel with a bright, uncoated finish. Screw machine length bits are shorter than jobber-length bits, which increases rigidity and reduces deflection in production drilling and close-tolerance work. The 118-degree split-free conventional point is a general-purpose geometry that starts cleanly on flat stock without a center punch in most setups. The right-hand cut and standard flute geometry suit a wide range of materials including mild steel, aluminum, brass, and plastics. Overall length is 2.75 inches with a flute length of 1.5625 inches.

This drill bit is suited for use in drill presses, CNC machining centers, turret lathes, and handheld power drills where a compact, rigid cutting tool is required. The reduced length compared to jobber bits makes it a preferred choice for production shops, maintenance technicians, and machinists drilling through thinner stock or working in confined setups where a longer bit would flex or chatter. General-purpose grade construction makes it appropriate for light to medium-duty metal, wood, and plastic applications across manufacturing, maintenance, and trade environments.

Key Features

• Letter M size — 0.2950 inch decimal equivalent for precise hole sizing
• 118-degree point angle — conventional general-purpose geometry for broad material compatibility
• High-speed steel construction — suitable for metal, wood, and plastic drilling
• Bright uncoated finish — no coating buildup concerns, easy to resharpen
• Screw machine length — shorter body increases rigidity and reduces deflection
• Right-hand cut — compatible with standard drill chucks and spindles

Compatibility

Designed as a general-purpose screw machine length drill bit compatible with any standard drill chuck accepting a straight shank in the 0.25 to 0.30 inch size range, including drill presses, lathes, and handheld power tools.

Installation Notes

Installation is performed by machinists, tool and die technicians, or maintenance professionals inserting the bit into a standard drill chuck and tightening securely before operation. Ensure the workpiece is clamped or fixtured before drilling to prevent movement. Use appropriate cutting fluid for extended tool life when drilling ferrous metals. Inspect the cutting edges before each use and resharpen or replace the bit when edge wear is visible to avoid overheating or oversized holes.