Osg 1294801 Extension Tap 10-32 Unf Spiral Point Hss

Product Description

The OSG 1294801 is a spiral point plug extension tap designed for threading operations in confined or deep-reach applications where a standard-length tap cannot access the work area. Built from high-speed steel with a steam oxide finish, it cuts right-hand internal threads in the 10-32 UNF thread form. The H3 thread limit provides consistent tolerance control for general-purpose threaded fastener applications. At 6 inches overall length with a 7/8 inch thread length and a plug chamfer, this tap is suited for through-hole threading in production and maintenance environments. Machinists and tool-and-die technicians are the primary users.

This extension tap is used in threading operations across aerospace, automotive, and general manufacturing environments. Its extended reach makes it appropriate for tapping holes in recessed bores, deep fixtures, or assemblies where clearance is restricted. Rated for use in cast iron, aluminum castings, aluminum, and carbon steel, it covers a broad range of common workpiece materials encountered in machine shop and field maintenance work. The 2-flute design aids chip ejection in through-hole applications, reducing the risk of tap breakage during production runs.

Key Features

• Spiral point geometry pushes chips forward during through-hole threading, reducing chip clogging
• 6 inch overall length provides extended reach for deep or restricted-access tapping locations
• H3 thread limit ensures consistent fit with standard 2B class-of-fit tolerance requirements
• Steam oxide finish improves lubrication retention and provides mild corrosion resistance during storage and use
• Reduced shank design allows use in standard tap holders and chucks without special tooling
• Compatible with cast iron, aluminum, aluminum castings, and carbon steel workpiece materials

Compatibility

Designed for through-hole threading applications producing 10-32 UNF internal threads with a 2B class of fit. Suitable for use in cast iron, aluminum casting, aluminum, and carbon steel workpieces as specified by the manufacturer.

Installation Notes

Extension taps of this type are installed by machinists or maintenance technicians using a tap wrench, tapping head, or CNC tapping cycle. Always ensure the workpiece is securely fixtured and that the tap is properly aligned with the drilled pilot hole before threading begins. Apply appropriate cutting fluid for the workpiece material to reduce heat and extend tool life. Discontinue use immediately if the tap shows signs of wear or if thread form degrades, as forcing a worn tap risks breakage in the hole.