Guhring 9055240065300 Cobalt Stub Drill Bit Letter F

Product Description

The GUHRING 9055240065300 is a cobalt screw machine length (stub) drill bit sized to Letter F, with a decimal diameter of 0.2570 inches (6.53 mm). Built to DIN 1897 specification from M35 cobalt steel, it features a 118-degree, 4-facet point with web thinning for reduced thrust and cleaner entry. The straw finish signals the cobalt heat treatment that extends tool life in demanding materials. Two regular spiral flutes evacuate chips efficiently. This bit is used by machinists, maintenance technicians, and metalworking tradespeople who need a short, rigid drill for precise holes in tight setups.

This drill bit is suited for drilling steel, stainless steel, cast iron, aluminum, and other non-ferrous materials in production and maintenance environments. The stub length keeps the tool rigid, reducing deflection when drilling without a drill press guide or in confined spaces. Its straight shank fits standard drill chucks and collet holders. The 3xD flute-to-diameter ratio and tapered web configuration support consistent performance across repetitive operations in both manual and CNC-assisted setups.

Key Features

• M35 cobalt steel construction for heat resistance and extended tool life in hard and abrasive materials
• 118-degree, 4-facet point with web thinning for reduced entry force and accurate self-starting
• Stub length overall length of 2.7559 inches for increased rigidity and reduced deflection
• Regular spiral flutes with tapered web for efficient chip evacuation
• Straight shank at 0.2571 inches diameter for compatibility with standard drill chucks and collets
• Manufactured to DIN 1897 specification for consistent dimensional tolerances

Compatibility

Designed as an OEM-style replacement stub drill bit for use in standard drill chucks and collet holders accepting a 0.2571-inch straight shank, suitable for applications specifying a Letter F drill in Series 5524.

Installation Notes

Installation and use should be performed by qualified machinists or maintenance technicians familiar with metalworking drill tooling. Ensure the drill press, mill, or handheld drill is powered off and secured before inserting or removing the bit from the chuck or collet. Verify shank seating and chuck tightness before operation. Always wear appropriate PPE including eye protection when drilling metal.