Osg HP255-4921 Solid Carbide Jobber Drill Bit 12.5mm

Product Description

The OSG HP255-4921 is a solid carbide jobber-length drill bit designed for high-performance drilling in ferrous materials. Built on the HP255 series platform, it features a 12.5 mm diameter, a 140-degree drill point angle, and an R-thinned point for accurate self-centering entry with reduced thrust. The WD1 coating provides wear resistance and thermal stability during demanding cutting operations. Overall length is 124 mm with a 77 mm flute length and a 14 mm straight-cylindrical shank. Two spiral flutes with a regular helix and tapered web configuration promote efficient chip evacuation. This bit ships at approximately 0.39 pounds and is sold individually.

The HP255-4921 is suited for production and maintenance drilling in steel, alloy steel, and cast iron. Its 5xD flute-to-diameter ratio supports moderate-depth applications including blind holes, cross holes, and through-hole drilling operations. Coolant-through capability makes it compatible with machining centers and CNC drilling setups where internal coolant delivery is available. Right-hand cut geometry is standard for conventional spindle rotation. Machinists, tool-and-die workers, and maintenance professionals working with ferrous workpieces will find this bit appropriate for both job shop and production environments.

Key Features

• Solid carbide construction for rigidity and wear resistance in ferrous materials
• WD1 coating for improved tool life and reduced heat buildup
• 140-degree drill point angle with R-thinned web for self-centering entry
• Coolant-through design compatible with internal coolant delivery systems
• 5xD flute length ratio supports blind hole, cross hole, and standard drilling applications
• Straight-cylindrical shank fits standard drill chucks and toolholders

Compatibility

Designed for use in steel, alloy steel, and cast iron workpieces (workpiece material codes P and K). Compatible with machining centers, drill presses, and CNC setups equipped with straight-shank toolholders sized for a 14 mm shank diameter.

Installation Notes

Installation and use should be performed by qualified machinists or tooling professionals familiar with carbide tooling. Secure the shank fully in a collet or drill chuck rated for the 14 mm shank diameter before engaging the spindle. When using coolant-through capability, verify that coolant pressure and flow rate match the machine tool specifications before running at full feed and speed. Inspect the cutting edges for chipping or wear before each use, as solid carbide is brittle and can fracture if run in a damaged condition.