Osg 5001900 Spiral Flute Tap 8-32 Unc Bottoming Hss

Product Description

The OSG 5001900 is a spiral flute bottoming tap designed for cutting right-hand internal threads to an 8-32 UNC specification in through and blind hole applications. Built from high-speed steel with a bright uncoated finish, this tap features a 50-degree helix angle and 3 right-hand spiral flutes that efficiently evacuate chips upward out of the hole during the tapping operation. The bottoming chamfer allows threading to the full depth of a blind hole, making it the correct choice when maximum thread engagement near the bottom of the bore is required. The H2 thread limit provides a close tolerance fit suited to 3B class-of-fit work.

This tap is suited for production and maintenance tapping in a range of metals including low-carbon steel, medium-carbon steel, high-carbon steel, cast iron, aluminum, and cast aluminum. The spiral flute geometry makes it especially effective in softer, gummy materials like aluminum where straight-flute taps tend to pack with chips. It is commonly used in machine shops, maintenance facilities, and field service environments where precise, clean internal threads in small fastener sizes are required.

Key Features

• Bottoming chamfer allows full thread depth in blind holes
• 50-degree helix angle promotes upward chip evacuation during cutting
• H2 thread limit ensures controlled tolerance for 3B class-of-fit applications
• High-speed steel construction provides toughness across a broad range of workpiece materials
• Bright uncoated finish suitable for general-purpose tapping with cutting fluid
• Right-hand flute direction matches standard right-hand thread cutting practice

Compatibility

Designed as an OEM-style replacement or standard tooling tap for 8-32 UNC threaded hole applications requiring a bottoming chamfer and H2 thread limit in 3B class-of-fit work. Compatible with standard tap handles, tapping heads, and CNC rigid tapping setups accepting the listed shank diameter.

Installation Notes

This tap should be installed and used by machinists or qualified tradespeople familiar with thread-cutting procedures. Always ensure the workpiece is securely fixtured and the tap is properly aligned to the drilled hole before engagement to prevent tap breakage. Use an appropriate cutting fluid for the workpiece material, particularly when tapping steel or cast iron. Follow standard shop practice for drill-to-tap hole size selection based on the 8-32 UNC thread specification.