Hertel 66694373 No. 38 Jobber Drill Bit 135 Degree Hss Tin

Product Description

The HERTEL 66694373 is a wire gauge No. 38 jobber-length drill bit designed for precision holemaking in metal, composite, and similar materials. It is manufactured from high speed steel with a titanium nitride (TiN) coating that extends tool life by increasing surface hardness and reducing friction at the cutting edge. The 135-degree split point geometry allows the bit to self-center on entry, reducing the need for a center punch and minimizing walking on hard or smooth surfaces. Overall length is 2.5 inches with a flute length of 1.4375 inches (1-7/16 inches). The straight cylindrical shank measures 0.1015 inches in diameter to match the decimal drill size. This is a heavy duty grade bit intended for production and trade use.

The 66694373 is suited for general holemaking applications where a No. 38 wire size (0.1015 inches decimal) is specified. Typical applications include tapping prep holes, clearance holes for small fasteners, and precision drilling in sheet metal, mild steel, aluminum, and plastics. The two-flute spiral configuration with regular spiral type and tapered web provides efficient chip evacuation in both hand-drill and drill-press setups. It is commonly used by machinists, electricians, and HVAC technicians requiring accurate small-diameter holes in metal enclosures, panels, and brackets.

Key Features

• No. 38 wire size, 0.1015 inches decimal diameter for precise gauge-matched hole sizing
• 135-degree split point with web thinning reduces thrust and self-centers on contact
• TiN coating improves wear resistance and extends cutting life over uncoated HSS
• Heavy duty grade high speed steel construction handles demanding production environments
• Right-hand cutting with regular spiral flutes for efficient chip removal
• Straight cylindrical shank fits standard drill chucks without adapters

Compatibility

Designed as a standard jobber-series replacement drill bit in No. 38 wire gauge size, compatible with any drill chuck accepting a 0.1015-inch straight cylindrical shank.

Installation Notes

Installation is performed by a machinist or qualified tradesperson using a drill press, hand drill, or CNC machine with an appropriate chuck. Secure the shank fully in the chuck before operation and verify spindle runout is within acceptable limits for the diameter being drilled. Use cutting fluid or coolant appropriate for the workpiece material to maximize bit life, particularly in steel. Inspect the cutting edges for wear or chipping before each use and replace the bit if the TiN coating is worn through at the cutting tip.