Chicago-latrobe 49409 Screw Machine Drill Bit 0.0995 in

Product Description

The CHICAGO-LATROBE 49409 is a heavy-duty screw machine length drill bit designed for high-speed steel cutting applications in metal fabrication and machining environments. With a 0.0995-inch diameter (Wire Size 39) and a 135-degree split point, this bit delivers fast starts without center punching and reduces walking on entry. The shortened screw machine length body provides added rigidity compared to jobber-length bits, making it the go-to choice for drill press, CNC, and turret lathe operations where chatter and deflection must be minimized. Machinists and tool-room technicians are the primary users of this bit.

This bit is built for drilling cast iron and steel workpieces in production and job-shop environments. The regular spiral flute geometry promotes efficient chip evacuation during through-hole and blind-hole drilling. Its straight-cylindrical shank seats securely in standard drill chucks and collet holders. The Series 159 designation indicates compliance with NAS 907 and ISO standards, making it suitable for aerospace, industrial, and general metalworking applications where specification conformance is required.

Key Features

• 0.0995-inch diameter, Wire Size 39, with diameter tolerance of +0.0000 to -0.0005 inches for precision fitment
• 135-degree split point reduces thrust and eliminates the need for center punching
• Web-thinned, parallel web configuration for improved cutting efficiency and reduced heat buildup
• Screw machine length body adds rigidity and reduces deflection in tight-clearance setups
• High speed steel construction with coating for extended tool life on cast iron and steel
• NAS 907 and ISO standards compliance for use in specification-controlled manufacturing

Compatibility

Designed for use on cast iron and steel workpieces. Fits standard drill chucks and collet holders that accept a straight-cylindrical shank. Suitable for drill press, CNC, and turret lathe setups requiring a screw machine length bit in the 0.0000 to 0.1000-inch diameter range.

Installation Notes

Machinists and tool-room technicians should ensure the shank is fully seated and the chuck is tightened securely before operation. Confirm spindle speed is appropriate for the workpiece material and bit diameter to avoid premature tool wear or breakage. Do not force the bit through material at excessive feed rates, particularly in harder steel grades. Inspect the cutting edges and point condition before each use; a damaged split point will compromise hole accuracy and increase thrust load.