Chicago-latrobe 68978 Letter I Hss Jobber Drill Bit 135

Product Description

The CHICAGO-LATROBE 68978 is a jobber-length drill bit sized at Letter I (0.2720 inches) from the Series 150DH heavy-duty line. Built from high-speed steel with a bright uncoated finish, it features a 135-degree split point and a parabolic flute geometry designed to evacuate chips efficiently during drilling. The web-thinned, tapered web configuration reduces thrust force at entry, making it well suited for production and maintenance drilling in steel alloy and similar ferrous materials. Right-hand cut with a straight-cylindrical shank, this bit is a reliable choice for machinists, millwrights, and maintenance technicians working with drill presses or hand-held power tools.

The 68978 is intended for drilling steel alloy as a primary workpiece material, and its parabolic flute design helps maintain chip flow in deeper hole applications. The straight-cylindrical shank at 0.2720 inches diameter fits standard three-jaw drill chucks without an adapter. With an overall length of 4.125 inches and a flute length of 2.875 inches, it provides adequate depth capacity for most through-hole and blind-hole tasks encountered in fabrication, mechanical maintenance, and general industrial work. The heavy-duty Series 150DH classification signals suitability for repetitive, high-cycle drilling operations.

Key Features

• Letter I size at 0.2720 inches decimal equivalent for precise hole sizing
• 135-degree split point reduces walking and lowers required entry thrust
• Parabolic flute geometry promotes efficient chip evacuation in deep holes
• Web-thinned tapered web further reduces axial cutting force
• High-speed steel construction handles steel alloy and general ferrous materials
• Bright uncoated finish — no coating buildup to affect hole tolerance

Compatibility

Designed as an OEM-style jobber-length drill bit compatible with standard three-jaw drill chucks accepting a 0.2720-inch straight-cylindrical shank, suitable for drill presses, magnetic drills, and variable-speed hand-held power tools used in general industrial and maintenance applications.

Installation Notes

Install and remove drill bits only with the machine fully powered down and the chuck key clear of the chuck. Secure the straight-cylindrical shank firmly in a properly sized chuck to prevent slipping under load. Use appropriate cutting fluid or coolant when drilling steel alloy to extend bit life and maintain hole-diameter tolerance. Inspect the cutting edges and split point before each use and replace the bit if chipping or excessive wear is observed.