Hertel 66692039 Screw Machine Drill Bit 27 Cobalt Tin

Product Description

The HERTEL 66692039 is a screw machine length drill bit designed for high-production drilling in metal fabrication, machining, and maintenance applications. Built from heavy-duty cobalt steel with a titanium nitride (TiN) coating, this bit delivers extended tool life in hard and abrasive materials including stainless steel, cast iron, and high-strength alloys. The 135-degree split point reduces thrust force and self-centers on contact, eliminating the need for a center punch in most setups. At 2-1/16 inches overall length, the screw machine format provides added rigidity compared to jobber-length bits, making it well suited for drill press and CNC turret work.

This bit is sized to wire gauge number 27, corresponding to 0.1440 inch decimal diameter, and fits applications requiring close-tolerance holes in that range. The straight-cylindrical shank seats directly in standard drill chucks and quick-change holders without adapters. Right-hand cutting direction suits conventional drilling operations. The 1-inch flute length and parallel web configuration with web thinning help clear chips efficiently in short-hole applications typical of screw machine and turret drilling work.

Key Features

• Cobalt tool material resists heat and wear in hard metals and stainless steel
• TiN coating adds surface hardness and reduces friction at the cutting edge
• 135-degree split point self-centers and reduces required thrust force
• Web-thinned parallel web improves chip evacuation in short-hole drilling
• Screw machine length provides greater rigidity than jobber-length alternatives
• Straight-cylindrical shank fits standard drill chucks and quick-change holders

Compatibility

Designed as an OEM-style replacement or direct-use screw machine drill bit for any standard drill chuck or quick-change holder accepting a 0.1440-inch straight-cylindrical shank.

Installation Notes

Installation is performed by machinists and maintenance technicians using drill presses, CNC turret machines, or hand-held power drills with a compatible chuck. Ensure the machine is powered down and the spindle is fully stopped before inserting or removing the bit. Verify chuck jaw engagement along the full shank contact length to prevent runout. Use appropriate cutting fluid or coolant for the workpiece material to maximize tool life, noting this bit does not support through-coolant delivery.