Cle-line C20481 Extra Length Drill Bit Letter E 1/4 in

Product Description

The CLE-LINE C20481 is an extra-length high-speed steel (HSS) drill bit in Letter E size, equivalent to 0.2500 inches in diameter. It is built for deep-hole drilling operations where a standard-length bit cannot reach. The bit features a 118-degree notched point with web thinning for easier penetration and reduced thrust, and an oxide finish that provides basic lubricity and corrosion resistance. With an 18-inch overall length and a 14-inch spiral flute, it delivers chip evacuation across extended reach applications. Licensed machinists, tool-and-die workers, and maintenance mechanics are the primary users.

This bit is suited for drilling through cast iron and steel in production and maintenance environments where deep bores are required. The straight cylindrical shank measures 0.2500 inches in diameter with a 4-inch shank length, making it compatible with standard drill chucks. The right-hand regular spiral and tapered web geometry support consistent, clean drilling in both manual and machine-feed setups. It falls under Series 1807 and is intended for general-purpose drilling at standard shop speeds.

Key Features

• Letter E size (0.2500 inches) with diameter tolerance of +0.0000 to -0.0010 inches for precision fitment
• 118-degree notched point with web thinning reduces entry thrust and improves self-centering
• 14-inch flute length supports deep-hole chip evacuation in extended-reach bores
• 18-inch overall length accommodates setups where standard bits fall short
• Oxide finish provides basic corrosion resistance and surface lubricity
• Meets ASME B94.11M standards for drill geometry and dimensional accuracy

Compatibility

Designed as a general-purpose extra-length drill bit for use in standard drill chucks accepting a 1/4-inch straight cylindrical shank. Primary workpiece materials are cast iron and steel.

Installation Notes

Install into a properly sized drill chuck and confirm secure clamping before operation. Secure the workpiece firmly to prevent movement during deep drilling. Use appropriate cutting fluid for steel and cast iron to extend tool life and maintain hole quality. Follow applicable shop safety standards and personal protective equipment requirements when operating drilling equipment.