Disston Company 571273 Cobalt Drill Bit 5/16 X 4.5 in 135 Split Point

Product Description

The DISSTON COMPANY 571273 is a 5/16-inch high-speed steel (HSS) cobalt drill bit with a jobber-length 4-1/2-inch overall length, designed for drilling into hard and abrasion-resistant metals. The 135-degree split point geometry features four cutting edges that allow immediate bite on contact, reducing the tendency for the bit to walk across a surface before engaging. With 8 percent cobalt content blended into the steel matrix, this bit maintains cutting efficiency at temperatures exceeding 1,000 degrees F, making it a reliable choice where standard HSS bits lose hardness and fail prematurely.

This bit is intended for trade and industrial applications where workpieces are composed of difficult-to-machine metals. Typical use cases include drilling into heat-treated steel, stainless steel, chrome alloys, manganese steel, titanium, and armor plate. The straight shank fits standard three-jaw drill chucks on corded or cordless drills and drill presses, making it compatible with common shop and field setups used by HVAC fabricators, pipefitters, electricians, and general mechanical contractors working with hardened fastener plates, brackets, or structural components.

Key Features

• 8 percent cobalt content sustains hardness and cutting performance at temperatures above 1,000 degrees F
• 135-degree split point with four cutting edges reduces walking and improves penetration rate on hard metals
• Jobber-length design balances reach and rigidity for general-purpose hole-making
• Straight shank fits standard three-jaw drill chucks without adapters
• Rated for heat-treated steel, stainless steel, chrome, manganese steel, titanium, and armor plate

Compatibility

Designed for use in standard three-jaw drill chucks; suitable for drilling heat-treated steel, stainless steel, chrome alloys, manganese steel, titanium, and armor plate as stated by the manufacturer.

Installation Notes

Install in a properly sized drill chuck and tighten securely with a chuck key before use. Use cutting fluid or coolant when drilling stainless steel or titanium to extend bit life and manage heat buildup. Reduce feed pressure as the bit breaks through the far side of the material to prevent grab or breakage. Follow applicable shop safety practices and wear appropriate eye protection during all drilling operations.