Hertel C.40N.3969 Screw Machine Drill Bit 1-9/16 in

Product Description

The HERTEL C.40N.3969 is a screw machine length drill bit designed for high-volume drilling in metal fabrication, machining, and general industrial applications. Manufactured from high-speed steel with a bright, uncoated finish, this bit features a 118-degree conventional point angle suited for drilling into a wide range of materials including mild steel, aluminum, and plastics. At 1-9/16 inches (1.5625 inches decimal) in diameter with a compact 7-3/4 inch overall length, the screw machine form factor provides added rigidity over jobber-length bits, reducing deflection and improving hole accuracy in production settings. Cutting direction is right hand.

This bit is intended for use in drill presses, CNC machining centers, lathes, and radial arm drills where stub-length rigidity is required. The general purpose grade and large diameter make it a practical choice for trade machinists, millwrights, and fabrication shops handling structural components, fixtures, or heavy plate work. The 4-7/8 inch flute length provides sufficient chip evacuation for the drilling depths typical of this bit class without sacrificing the short-body stiffness that screw machine geometry delivers.

Key Features

• 1-9/16 inch (1.5625 inch decimal) diameter for large-bore drilling
• 118-degree conventional point angle for general purpose material entry
• High-speed steel construction for durability across ferrous and non-ferrous materials
• Bright, uncoated finish suitable for use with standard cutting fluids
• Screw machine (stub) length body for increased rigidity and reduced deflection
• Right-hand cutting direction, compatible with standard drill spindles

Compatibility

Designed as a general purpose screw machine length drill bit for use in standard drill chucks and collet holders accepting 1-9/16 inch shank diameters across industrial drilling equipment.

Installation Notes

Installation and use should be performed by qualified machinists or millwrights familiar with large-diameter drilling operations. Ensure the workpiece is securely clamped and the machine spindle is powered down before mounting or removing the bit. Use appropriate cutting fluid for the material being drilled to extend tool life and maintain hole quality. At this diameter, feed rates and spindle speeds should be set conservatively per standard machining data references to prevent tool damage or workpiece movement.