Osg 1141300 Straight Flute Tap 3/8-16 Unc 4 Flutes Hss

Product Description

The OSG 1141300 is a straight flute tap designed for cutting 3/8-16 UNC internal threads in a wide range of materials. Built from high-speed steel with a bright, uncoated finish, it features a plug chamfer that makes it suitable for through-hole and partial-depth tapping applications. The tap runs 2-15/16 inches overall with a 1-1/4 inch thread length and an H5 thread limit, delivering consistent tolerance control for 2B class of fit threads. With 4 flutes, it channels chips efficiently in the straight-flute configuration. Installation is performed by hand or with a tapping machine.

This tap is intended for use in aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel. It fits standard production and maintenance tapping operations in manufacturing, machining, and general metalworking environments. The plug chamfer provides a gradual thread lead-in, making it a reliable choice when starting a tap in a drilled hole where a full-length thread is required but the hole is not entirely through.

Key Features

• 3/8-16 UNC thread form with 16 threads per inch and right-hand thread direction
• H5 thread limit for controlled 2B class of fit tolerances
• Plug chamfer for versatile use in through-holes and deep blind holes
• High-speed steel construction for durability across a broad material range
• Bright, uncoated finish - no coating buildup to affect thread dimensions
• 4 straight flutes for chip management in short-chipping materials

Compatibility

Designed for tapping 3/8-16 UNC threads in aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel workpieces. Suitable for use with standard 3/8-inch tap wrenches and tapping heads accepting a 0.381-inch shank diameter.

Installation Notes

Machinists and tool-and-die technicians should ensure the workpiece is properly clamped and the pilot hole is drilled to the correct tap drill size for 3/8-16 UNC before starting. Apply appropriate cutting fluid to extend tap life and improve thread finish. Use a tap wrench or tapping attachment that holds the shank securely to maintain axial alignment and prevent tap breakage. Follow standard shop practices and machine guarding requirements when operating tapping equipment.