Osg 1650509608 Spiral Flute Tap 8-32 Unc Bottoming 3B

Product Description

The OSG 1650509608 is a spiral flute bottoming tap designed for cutting 8-32 UNC internal threads in a wide range of ferrous and non-ferrous metals. The 45-degree helix angle drives chips up and out of the hole, making this tap well suited for blind-hole applications where chip evacuation is critical. Built from powdered metal with a V coating for added wear resistance, it produces 3B-class threads and carries an H2 thread limit for consistent tolerance control. Overall length is 2.48 inches with a thread length of 0.251 inches and a tapping depth of 21.00 millimeters. Machinists, tool-and-die technicians, and maintenance mechanics are the primary users of this tool.

This tap is designed for blind-hole threading operations in alloy steel, aluminum, cast aluminum, cast iron, hardened steel, high-carbon steel, low-carbon steel, medium-carbon steel, and stainless steel. The bottoming chamfer allows threading to the full depth of a blind hole with minimal unthreaded lead length remaining at the bottom. It fits standard tap holders and is appropriate for both CNC machining centers and manual tapping operations where a right-hand 8-32 UNC thread is required.

Key Features

• 45-degree helix angle promotes efficient chip evacuation in blind holes
• Bottoming chamfer allows threading to near-full depth in blind holes
• Powdered metal construction with V coating for extended tool life and wear resistance
• H2 thread limit ensures consistent 3B-class thread tolerance
• Right-hand flute direction and right-hand thread for standard tapping setups
• No coolant-through requirement simplifies tooling setup

Compatibility

Designed as an OEM-style threading tool for standard 8-32 UNC blind-hole applications across compatible tap holders and tapping attachments accepting the specified shank and square drive dimensions.

Installation Notes

This tap is installed by a machinist or maintenance mechanic using a standard tap wrench, tapping head, or CNC toolholder sized to the 0.168-inch shank diameter. Ensure the workpiece is securely fixtured and the pilot hole is drilled to the correct tap drill size for 8-32 UNC before tapping. Apply appropriate cutting fluid for the workpiece material to extend tool life and improve thread quality. Do not reverse the tap under load without first backing off to break chips, particularly in deep blind holes.