Hertel 66692559 Jobber Drill Bit 7/16 Inch Hss Tialn

Product Description

The HERTEL 66692559 is a 7/16 inch (0.4375 inch) diameter jobber-length drill bit engineered for heavy-duty holemaking in metal and general fabrication applications. Built from high speed steel with a TiAlN coating, it runs at higher surface temperatures than uncoated HSS and resists wear on harder materials. The 135-degree split point reduces thrust force and self-centers without a pilot hole. With a 5-1/2 inch overall length and a 4-1/16 inch flute length, it fits standard drill chucks and drill presses used by machinists, pipefitters, and metal fabricators on the shop floor or in the field.

This bit is suited for production drilling and general-purpose holemaking in ferrous and non-ferrous metals, including steel, cast iron, and aluminum. The right-hand spiral flute with regular helix promotes chip evacuation in through-hole and blind-hole drilling scenarios. A web-thinned, tapered-web construction reduces the dead zone at the tip and lowers required feed force, making it practical on both machine tools and handheld power drills. It is sold individually and is sized within the 0.4000 to 0.5000 inch decimal range covered by the NAS specification designation.

Key Features

• 7/16 inch (0.4375 inch) diameter straight-cylindrical shank fits standard chucks with no adapter
• TiAlN coating extends tool life on harder materials by resisting heat buildup at the cutting edge
• 135-degree split point self-centers on contact and reduces required thrust force
• Web-thinned, tapered-web design lowers cutting resistance and improves chip clearance
• 2-flute right-hand spiral construction promotes efficient chip evacuation in metal drilling
• Heavy-duty grade construction meets NAS specification designation for industrial holemaking

Compatibility

Designed as a jobber-series replacement or direct-use drill bit for any application requiring a 7/16 inch straight-shank HSS drill in NAS-spec tooling programs.

Installation Notes

Installation is performed by machinists, pipefitters, or qualified tradespeople using a drill press, milling machine, or handheld power drill with a compatible chuck. Secure the straight-cylindrical shank firmly in the chuck before operation and verify concentricity to avoid premature edge wear. Use appropriate cutting fluid or coolant for the workpiece material when drilling ferrous metals, as this bit does not support coolant-through delivery. Follow applicable shop safety standards and personal protective equipment requirements when operating rotary cutting tools.