Hertel 16704439 Screw Machine Drill Bit Letter O

Product Description

The HERTEL 16704439 is a solid carbide screw machine length drill bit sized to Letter O (0.3160 inches decimal equivalent) with a 135-degree split-point geometry. Screw machine length bits are shorter than jobber-length equivalents, giving them added rigidity for accurate, chatter-free entry in production and maintenance drilling applications. The slow-spiral flute design controls chip evacuation in tough materials, and the bright, uncoated carbide surface is suited for use in cast iron, nickel alloy, stainless steel, titanium alloy, and tool steel. This bit is intended for use by machinists and tool-and-die professionals working on manual or CNC machines.

This drill bit is built for hard and abrasive workpiece materials where high-speed steel tooling underperforms. The 135-degree point reduces the thrust force needed to start a hole and self-centers without a pilot hole, making it practical in tight production schedules. A straight cylindrical shank accepts standard drill chucks without adapters. Typical applications include aerospace component work, toolroom maintenance, and precision hole sizing in ferrous and exotic-alloy stock. With an overall length of 2-15/16 inches and a flute length of 1-11/16 inches, this bit fits standard screw machine and knee-mill setups.

Key Features

• Solid carbide construction for superior hardness and wear resistance in abrasive materials
• 135-degree split-point geometry reduces thrust and self-centers on contact
• Slow-spiral flute design aids chip control in gummy or stringy alloys
• Bright, uncoated finish suitable for use with cutting fluids across multiple material types
• Right-hand cut with straight cylindrical shank for direct chuck mounting
• Screw machine length provides extra rigidity compared to jobber-length bits

Compatibility

Designed for use in drilling cast iron, nickel alloy, stainless steel, titanium alloy, and tool steel workpieces. Fits any standard drill chuck accepting a straight cylindrical shank in the 0.3000 to 0.3500 inch size range.

Installation Notes

Installation and use should be performed by qualified machinists familiar with cutting tool setup and machine operation. Power down and de-energize the machine spindle completely before inserting or removing the bit from the chuck. Ensure the shank is fully seated and the chuck is tightened evenly before starting the cut. Appropriate cutting fluid or coolant should be applied at the workpiece per shop practice, as this bit does not support coolant-through delivery.