Osg 1294500 Spiral Point Extension Tap 10-24 Unc Hss

Product Description

The OSG 1294500 is a spiral point extension tap designed for threading 10-24 UNC holes in production and maintenance applications. Built from high speed steel (HSS) with a bright/uncoated finish, it features a plug chamfer entry and a right-hand flute direction suited for through-hole threading. The extended 4-inch overall length (OAL) provides reach in applications where a standard-length tap cannot access the workpiece. With a 2-flute design and H3 thread limit, the 1294500 produces 2B and 3B class of fit threads with reliable dimensional consistency across a range of materials.

This tap is appropriate for threading operations in aluminum, carbon steel, cast iron, and hardened steel workpieces. The spiral point design pushes chips forward ahead of the cutting action, making it well-suited for through-hole applications on CNC machining centers, drill presses, and manual tapping setups. The reduced shank and extended neck length of 0.874 inches allow it to reach into recessed or deep-pocket features that standard taps cannot clear. It is commonly used in machine shops, maintenance facilities, and production environments where extended reach is a job requirement.

Key Features

• Spiral point geometry pushes chips forward, ideal for through-hole threading
• 4-inch OAL provides extended reach for recessed or deep-pocket workpieces
• H3 thread limit for accurate 2B and 3B class of fit thread production
• High speed steel construction compatible with aluminum, carbon steel, cast iron, and hardened steel
• Plug chamfer entry for progressive thread engagement
• Reduced shank design with 0.874-inch neck length for clearance in tight setups

Compatibility

Designed for through-hole tapping in materials including aluminum, carbon steel, cast iron, and hardened steel. Produces 10-24 UNC threads to 2B and 3B class of fit specifications.

Installation Notes

Installation is performed by machinists and tool and die tradespeople using standard tap holders, floating tap chucks, or rigid tapping attachments. Ensure the workpiece is securely fixtured and the pilot hole is drilled to the correct tap drill diameter for a 10-24 thread before starting. Apply appropriate cutting fluid for the workpiece material to extend tool life and improve thread quality. Do not exceed the rated capacity of the tapping attachment or reverse the tap under load without confirming synchronization.