Chicago-latrobe 48543 Screw Machine Drill Bit 43/64 in

Product Description

The CHICAGO-LATROBE 48543 is a screw machine length drill bit designed for high-production drilling in metal fabrication and machining environments. Built from coated high speed steel, it measures 43/64 inch (0.6719 inches) in diameter with an overall length of 4-5/8 inches and a flute length of 2-7/8 inches. The 118-degree standard point angle and web-thinned tip reduce entry force and improve centering on flat and curved surfaces. The 2-flute spiral configuration evacuates chips efficiently during through-hole and blind-hole operations. Licensed machinists, tool-and-die technicians, and metalworking shops are the primary installers and users of this bit.

The 48543 fits screw machine and turret lathe applications where a shorter, stiffer bit length reduces deflection and improves hole accuracy at higher feed rates. Primary workpiece materials include cast iron, non-ferrous metals, and steel. The straight-cylindrical shank seats in standard drill chucks and quick-change toolholders without modification. General-purpose grade classification makes it a practical stock item for shops running mixed-material production or MRO maintenance drilling tasks where a dedicated premium grade is not warranted.

Key Features

• Coated high speed steel construction for improved wear resistance on steel and cast iron
• 118-degree standard point angle with web-thinned tip for reduced thrust and self-centering entry
• Screw machine (stub) length body at 4-5/8 inches overall for increased rigidity and reduced deflection
• Regular spiral, 2-flute design promotes efficient chip evacuation in through-hole drilling
• Straight-cylindrical shank compatible with standard drill chucks and quick-change toolholding systems
• Diameter tolerance of +0.0000 to -0.0012 inches meets ISO standards for general-purpose hole quality

Compatibility

Rated for use on primary workpiece materials including cast iron, non-ferrous metal, and steel. Designed as a general-purpose screw machine length drill bit for use in drill presses, turret lathes, screw machines, and hand-held drill applications using standard straight-shank toolholding.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists or toolroom technicians familiar with metal cutting operations. Secure the straight shank fully in the chuck or toolholder before operation and verify runout before beginning a production run. Always power down and de-energize the machine spindle before changing or inspecting bits. Follow shop safety protocols including appropriate chip guarding and eye protection when drilling ferrous and non-ferrous materials.