Chicago-latrobe 45657 Cobalt Drill Bit Set 20 Pc

Product Description

The CHICAGO-LATROBE 45657 is a 20-piece cobalt jobber length drill bit set covering wire gauge sizes 80 through 61, with decimal inch sizes ranging from 0.0135 inches to 0.0390 inches. Built from cobalt tool steel with a gold finish, these bits are engineered for high-performance metalworking and multipurpose drilling applications. The 135-degree split-point tip eliminates the need for a center punch by self-centering on contact and reducing walking on hard or smooth surfaces. Straight shanks and standard jobber length proportions make these bits compatible with most drill chucks and driver setups. The set ships in a metal storage case that indexes all 20 sizes for fast identification on the job.

This set is intended for machinists, tool-and-die technicians, maintenance mechanics, and metalworking trades that regularly drill small-diameter holes in steel, stainless, cast iron, and other hard metals. The cobalt construction provides heat resistance that holds up under the friction generated when drilling tough alloys without cutting fluid in many situations. With 20 incrementally sized bits from 0.0135 to 0.0390 inches, the set covers a wide range of precision hole sizes in a single kit, reducing the need to source individual wire-gauge bits for close-tolerance work.

Key Features

• Cobalt tool steel construction resists heat buildup when drilling hard metals and stainless steel
• 135-degree split-point geometry self-centers on contact, reducing walk without center-punching
• Gold finish serves as a surface treatment indicator and provides light lubricity
• 20-piece set spans wire gauge sizes 80 through 61 in incremental decimal inch steps
• Straight shank fits standard drill chucks and collet-style holders
• Metal indexed storage case keeps all 20 sizes organized and protected

Compatibility

Designed for metalworking and multipurpose drilling applications requiring small wire-gauge hole sizes. Straight-shank jobber length format fits standard 3-jaw drill chucks on bench drills, drill presses, and CNC equipment accepting the shank diameters in this size range.

Installation Notes

Secure the workpiece firmly before drilling to prevent movement on breakthrough, especially with small-diameter bits that are prone to breakage under lateral load. Use appropriate cutting fluid or lubricant when drilling stainless steel or hardened alloys to extend bit life. Operate at the correct surface footage for the workpiece material and bit diameter — excessive speed generates heat that degrades cobalt bits prematurely. Inspect the split point for chipping before each use; a damaged tip will produce oversize or off-location holes.