Chicago-latrobe 70320 Letter T Jobber Drill Bit Hss Tin

Product Description

The CHICAGO-LATROBE 70320 is a jobber length drill bit sized to Letter T (0.3580 inches) and built from high speed steel with a titanium nitride (TiN) coating. The TiN coating reduces friction and extends cutting life compared to uncoated HSS bits. At 4-7/8 inches overall length with a 3-1/2 inch flute, this is a standard jobber proportion suited to drill presses, hand drills, and CNC drilling operations. The 118-degree standard point angle and web-thinned tip reduce thrust and improve center starting on flat stock. This bit is installed and used by machinists, maintenance technicians, and metalworking tradespeople working in production or job-site environments.

This drill bit is designed for general-purpose drilling in cast iron and steel. The right-hand spiral flute efficiently evacuates chips from the bore during drilling. The straight cylindrical shank at 0.3580 inches diameter fits standard three-jaw chucks without adapters. The regular spiral and tapered web configuration make it appropriate for both through-hole and blind-hole applications in metal fabrication, maintenance repair, and manufacturing environments. It is sold individually as a single-piece unit.

Key Features

• Letter T size: 0.3580 inches diameter with a diameter tolerance of -0.0010 to 0.0000 inches
• Titanium nitride (TiN) coating for reduced friction and extended tool life
• 118-degree standard point angle with web-thinned tip for reduced entry thrust
• Right-hand cut, 2-flute regular spiral for efficient chip evacuation
• Straight cylindrical shank fits standard drill chucks directly
• Conforms to DIN 338 standard for jobber length geometry

Compatibility

Designed as a general-purpose jobber length drill bit for use in standard three-jaw drill chucks on hand drills, drill presses, and CNC drilling equipment. Primary workpiece materials are cast iron and steel.

Installation Notes

Secure the shank fully in the chuck before drilling and verify the chuck key is removed before powering the drill. Power down and de-energize any machine tool before changing bits. Use cutting fluid or coolant when drilling ferrous metals to preserve coating life and edge sharpness, noting this bit does not have a through-coolant channel. Follow applicable machine tool safety standards and shop safety procedures when operating drilling equipment.