Osg HP253-2598 Screw Machine Drill Bit 0.2598 in Carbide

Product Description

The OSG HP253-2598 is a screw machine length drill bit engineered for high-performance drilling in steel, alloy steel, and cast iron. It measures 0.2598 inches (6.60 mm) in diameter with a 140-degree split point and solid carbide construction throughout. The R-thinned web reduces thrust and improves chip evacuation at entry. Coolant-through capability makes this bit well-suited for deep-hole applications where heat buildup and chip clearing are primary concerns. Machinists, tool-and-die technicians, and production floor operators working with ferrous metals will find this bit appropriate for demanding, tight-tolerance work.

The HP253-2598 fits production drilling applications in machine shops, fabrication facilities, and industrial maintenance environments. Its screw machine (stub) length provides added rigidity compared to jobber-length bits, reducing deflection in high-feed or automated setups. The 3xD flute-to-diameter ratio supports chip flow in materials like mild steel, alloy steel, and cast iron. The straight-cylindrical shank with an 8.00 mm (0.315 inches) shank diameter seats securely in standard drill chucks and collet systems.

Key Features

• Solid carbide construction for extended tool life in ferrous workpiece materials
• 140-degree drill point angle reduces thrust and improves hole entry accuracy
• R-thinned, tapered web design lowers cutting resistance and aids chip removal
• Coolant-through design supports heat management in deep-hole and high-speed operations
• Screw machine length provides increased rigidity over jobber-length alternatives
• Right-hand spiral flute with regular helix for consistent chip evacuation

Compatibility

Designed for drilling in steel, alloy steel, and cast iron workpieces. Part of the OSG HP253 series, covering the 0.2500 to 0.3000 inch (6.50 to 8.00 mm) diameter range.

Installation Notes

Install in a compatible drill chuck or collet sized for an 8.00 mm straight-cylindrical shank before starting the machine. Verify spindle speed and feed rate are set per the material being drilled before engaging the cut. Connect coolant supply lines if using the through-coolant feature, and confirm adequate coolant pressure and flow before running. Inspect the cutting edge for chipping or wear before each use, as carbide tooling is brittle and should never be used in a visibly damaged condition.