Osg 2916508 Spiral Flute Tap 4-40 Unc Ticn Vanadium Hss

Product Description

The OSG 2916508 is a spiral flute tap designed for cutting internal 4-40 UNC right-hand threads in a wide range of metallic workpiece materials. Manufactured from vanadium high-speed steel and finished with a titanium carbonitride (TiCN) coating, this tap delivers improved wear resistance and surface hardness compared to uncoated HSS alternatives. The modified bottoming chamfer allows threading closer to the bottom of blind holes while still providing controlled chip evacuation through the 45-degree right-hand spiral flutes. With a thread limit of H4, it holds tight tolerances appropriate for precision fastener applications. Machinists and toolroom technicians working in job shop, production, or MRO environments will find this tap well-suited for close-tolerance threading work.

The OSG 2916508 is intended for threading operations in alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel. The spiral flute geometry promotes upward chip evacuation, making it particularly effective in blind-hole applications where chip packing is a concern. At 1-7/8 inches overall length with a 0.367-inch shank diameter, this tap fits standard tap holders and chucks used in CNC machining centers, drill presses, and manual tapping setups. It is sold individually with a minimum order quantity of one.

Key Features

• 4-40 UNC thread form, right-hand direction, H4 thread limit for precision tolerance control
• Vanadium high-speed steel construction for enhanced toughness and tool life
• TiCN coating increases surface hardness and reduces friction against the workpiece
• 45-degree right-hand spiral flutes evacuate chips upward out of blind holes
• Modified bottoming chamfer allows threading near the base of blind holes
• Compatible with alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel

Compatibility

Rated for use in alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel workpieces. Fits standard tap holders and collet chucks accepting a 0.367-inch shank diameter. Part of the OSG Series 290 spiral flute tap line.

Installation Notes

Installation and use should be performed by a qualified machinist or toolroom technician. Secure the workpiece and ensure the spindle is properly aligned before beginning the tapping operation. Use appropriate cutting fluid for the workpiece material to extend tool life and maintain thread quality. Always bring the machine to a complete stop before inspecting the tap or clearing chips from the flutes.