Chicago-latrobe 49406 Screw Machine Drill Bit 0.1065 in

Product Description

The CHICAGO-LATROBE 49406 is a screw machine length drill bit designed for high-production drilling in ferrous metals including cast iron and steel. At 0.1065 inches in diameter (Wire Size 36), this heavy-duty bit features a 135-degree split point that reduces walking and decreases the thrust required to start the hole. The two-flute spiral design with web-thinned, parallel-web construction promotes efficient chip evacuation. The straight-cylindrical shank seats securely in standard drill chucks. Manufactured from coated high speed steel, this bit is built for repeated use in demanding shop and field applications where dimensional accuracy is critical.

The 49406 is suited for drilling operations in cast iron and steel workpieces where a short, rigid bit is preferred over a jobber-length drill. Screw machine length bits are commonly used in CNC drilling centers, drill presses, and hand-held power tools where reduced bit overhang improves hole straightness and minimizes deflection. The overall length of 1-13/16 inches and flute length of 13/16 inches keep the cutting zone close to the chuck, making this bit a standard choice in production machining, metal fabrication, and maintenance environments. It conforms to NAS 907 specification under the NAS designation and meets ISO standards.

Key Features

• 135-degree split point reduces walking and lowers entry thrust on hard metals
• Web-thinned parallel web improves chip clearance and reduces heat buildup
• Coated high speed steel construction extends cutting life in steel and cast iron
• Screw machine length body provides superior rigidity and hole accuracy versus jobber-length bits
• Right-hand cut, two-flute spiral design compatible with standard drill equipment
• Diameter tolerance held to +0.0000 to -0.0005 inches for consistent hole sizing

Compatibility

Designed for drilling cast iron and steel workpieces. Compatible with standard drill chucks accepting straight-cylindrical shanks. Part of CHICAGO-LATROBE Series 159 heavy-duty screw machine drill bits.

Installation Notes

This bit is installed and serviced by machinists, tool-and-die tradespeople, and maintenance technicians. Secure the straight shank fully in the drill chuck before operation and confirm runout is within acceptable limits. Use appropriate cutting fluid or coolant for steel applications to extend bit life, even though coolant-through is not available on this bit. Inspect the cutting edges for wear before each use and replace when the point geometry is degraded to avoid oversized or tapered holes.