Osg 1600707 Straight Flute Tap 5/16-18 Unc Plug Hss

Product Description

The OSG 1600707 is a straight flute tap designed to cut 5/16-18 UNC internal threads in through-hole and open-setup machining applications. Built from high-speed steel with a nitride/oxide combination coating, it delivers improved wear resistance and helps reduce galling during tapping operations. The plug chamfer style provides a gradual thread lead-in, making it well-suited for through-hole work where full thread engagement near the bottom is not required. With 4 flutes and an H3 thread limit, this tap holds tight tolerances consistent with a 3B class of fit, meeting standard UNC thread specifications for general fastener applications.

This tap is intended for use in machine shop, maintenance, and production environments where 5/16-18 UNC threads are required. It is rated for use in aluminum and cast iron workpieces. The right-hand thread direction suits conventional tapping setups on drill presses, CNC machining centers, and hand tapping fixtures. The 101C series designation indicates an OSG standard straight flute tap geometry appropriate for shorter-chipping materials like cast iron and aluminum, where flute evacuation demands are lower.

Key Features

• 5/16-18 UNC thread size with right-hand thread direction
• Plug chamfer for through-hole tapping with gradual thread lead-in
• High-speed steel construction with nitride/oxide coating for wear resistance
• H3 thread limit, 3B class of fit for standard UNC tolerance compliance
• 4 straight flutes suited for aluminum and cast iron applications
• No coolant-through requirement simplifies tooling setup

Compatibility

Designed for cutting 5/16-18 UNC internal threads in aluminum and cast iron workpieces. Compatible with standard tap holders, drill press chucks, and CNC tapping attachments accepting the 0.318-inch shank diameter of this tap.

Installation Notes

This tap should be installed in a properly sized tap holder or chuck rated for the shank diameter before use. Ensure the workpiece is securely fixtured and that an appropriate cutting fluid or tapping compound is applied for the material being tapped. Power down or de-energize any machine before changing tooling. Always verify thread size and chamfer type against the application requirements before starting the tapping cycle.