Osg 1120702 Straight Flute Tap 5/16-18 Unc 4 Flutes Plug

Product Description

The OSG 1120702 is a straight flute tap designed to cut 5/16-18 UNC internal threads in a wide range of ferrous and non-ferrous materials. Manufactured from high-speed steel, it features a plug chamfer and an H3 thread limit, delivering precise 3B class-of-fit threads suited to standard fastener applications. With four flutes and a 1-1/8 inch thread length, the tap provides stable chip formation during through-hole and blind-hole tapping operations. Overall length is 2-23/32 inches. Right-hand thread direction. This tool is part of the OSG Series 101 line and is installed by machinists, maintenance mechanics, and field service technicians working in production or repair environments.

This tap is suited for hand tapping and machine tapping operations in both production and maintenance settings. The plug chamfer style makes it appropriate for through-hole applications where the tap can be run fully through the workpiece. The H3 thread limit and 3B class of fit ensure compatibility with standard UNC fastener tolerances across a broad range of machining scenarios.

Key Features

• 5/16-18 UNC thread form with right-hand thread direction
• Plug chamfer for through-hole tapping applications
• H3 thread limit for 3B class-of-fit precision
• Four flutes for stable chip evacuation during cutting
• High-speed steel construction for durability across multiple materials
• No coolant-through requirement - compatible with standard tapping fluid application

Compatibility

Rated for use in aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel. Designed as a standard straight flute tap for 5/16-18 UNC thread cutting in both hand and machine tapping setups.

Installation Notes

Tapping operations should be performed by qualified machinists or mechanics familiar with thread cutting procedures and proper tap alignment. Always use an appropriate tapping fluid or cutting oil matched to the workpiece material to extend tool life and improve thread quality. Secure the workpiece fully before beginning the tapping operation, and back the tap out periodically to clear chips when working in blind holes. Follow applicable shop safety practices and machine-specific operating procedures when using power tapping equipment.