Chicago-latrobe 46477 Cobalt Jobber Drill Bit 0.2638 in

Product Description

The CHICAGO-LATROBE 46477 is a cobalt jobber-length drill bit designed for high-performance drilling in steel and stainless steel. Part of the Series 550 line, it features a 135-degree split point that reduces walking and lowers thrust requirements at entry. The straw-finish cobalt construction provides heat resistance needed when drilling work-hardening materials. The two-flute, right-hand spiral geometry handles chip evacuation efficiently in through-hole and blind-hole applications. With an overall length of 3.9764 inches and a straight cylindrical shank, it fits standard drill chucks without adapters. This bit is built to DIN 338 and NAS 907 Type J specifications and is suited for machinists, maintenance technicians, and fabricators working with ferrous metals.

The 46477 is well matched to production drilling and maintenance repair operations where steel and stainless steel are the primary workpiece materials. The 0.2638-inch diameter with a tapered web and web-thinned geometry makes it effective for hand-held or machine-fed setups on structural steel, plate, tubing, and formed stainless components. It covers the 0.2500 to 0.3000-inch drill size range bracket and is sold individually, making it practical for spot replacement in a drill index or as a dedicated bit for a recurring hole size.

Key Features

• Cobalt construction with straw coating for heat resistance in steel and stainless steel drilling
• 135-degree split point reduces thrust and prevents bit walking on entry
• Web-thinned, tapered web design lowers cutting resistance
• Right-hand, regular spiral flute for efficient chip evacuation
• Meets DIN 338 and NAS 907 Type J standards for dimensional consistency
• Straight cylindrical shank fits standard drill chucks directly

Compatibility

Designed for use in steel and stainless steel workpieces. Straight cylindrical shank fits standard keyed and keyless drill chucks on hand drills, drill presses, and CNC machining centers accepting a 0.2638-inch shank diameter.

Installation Notes

A licensed machinist or qualified maintenance technician should secure the workpiece and verify chuck grip before drilling. Use appropriate cutting fluid or lubricant when drilling stainless steel to manage heat buildup and extend bit life. Do not exceed the recommended feed rate for cobalt bits in hard materials, as excessive pressure can cause premature tip failure. Follow applicable shop safety codes and wear appropriate eye protection.