Osg 1019902 Straight Flute Bottoming Tap 8-32 Unc Hss

Product Description

The OSG 1019902 is a straight flute bottoming tap designed for threading operations in a wide range of metallic materials. It cuts an 8-32 UNC right-hand thread and is built from high-speed steel for durability under repeated use. With a bottoming chamfer, this tap is suited for producing threads to the bottom of blind holes where through-tapping is not possible. The 3-flute design provides adequate chip clearance while maintaining good thread form. Overall length is 2.125 inches with a thread length of 0.75 inches. This tap carries an H7 thread limit for close tolerance work and is intended for use by machinists, tool and die tradespeople, and maintenance mechanics.

This tap is applied in production and maintenance machining environments where precise, close-tolerance internal threads are required in blind holes. It is rated for use in aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel. Applications include threading tapped holes in fixtures, machine components, and fabricated assemblies. The straight flute configuration makes it well suited for short-chipping materials such as cast iron and aluminum alloys.

Key Features

• Bottoming chamfer allows threading to the bottom of blind holes
• High-speed steel construction handles a broad range of ferrous and non-ferrous materials
• H7 thread limit suits close-tolerance tapping applications
• 3-flute straight design provides chip clearance in short-chipping materials
• Right-hand thread direction, 8-32 UNC specification
• Compact overall length of 2.125 inches fits standard tap handles and drill press setups

Compatibility

Designed as a standard replacement or stock tap for 8-32 UNC bottoming applications in aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel workpieces.

Installation Notes

This tap is installed by machinists using a standard tap handle, T-handle wrench, or machine tapping head rated for the tap size. Always ensure the pilot hole is drilled to the correct tap drill diameter for 8-32 UNC before tapping. Apply appropriate cutting fluid for the material being tapped to extend tool life and improve thread quality. Avoid forcing the tap; back off periodically to break chips and prevent binding or breakage.