Osg 1101400 Straight Flute Bottoming Tap 3/8-16 Unc Hss

Product Description

The OSG 1101400 is a straight flute bottoming tap designed for threading operations in a wide range of ferrous and non-ferrous metals. Built from high-speed steel with a bright uncoated finish, this tap cuts a 3/8-16 UNC right-hand thread and is engineered to thread close to the bottom of a blind hole. It carries an H1 thread limit, which holds tight tolerance on the finished thread. The 4-flute straight flute design channels chips back out of the hole, making it well suited to through-hole applications and shallow blind bores where chip evacuation is straightforward. Overall length is 2-15/16 inches with a thread length of 1-1/4 inches.

This tap is used in machine shop, maintenance, and field repair work wherever a 3/8-16 UNC thread must be cut into a pre-drilled hole. Material applications include aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel. The bottoming chamfer style allows threading to within a few thread pitches of the bottom of a blind hole, making it the correct choice when a plug or taper tap has already started the hole and full-depth thread engagement is required. It is appropriate for use in manual tap handles, tapping heads, and CNC tapping operations.

Key Features

• Bottoming chamfer for threading close to the bottom of blind holes
• H1 thread limit for controlled tolerance on 3/8-16 UNC threads
• High-speed steel construction for durability across steel, cast iron, and aluminum workpieces
• 4-flute straight flute geometry for efficient chip removal in through-hole and shallow blind-hole work
• Bright uncoated finish compatible with cutting oils and water-soluble coolants
• Right-hand thread direction, no coolant-through - compatible with standard toolholding

Compatibility

Designed for cutting 3/8-16 UNC right-hand threads in aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel. Part of the OSG Series 101 straight flute tap line.

Installation Notes

This tap is installed and used by machinists, maintenance technicians, and trade professionals performing threaded-hole repair or fabrication. Always use the correct tap drill size for 3/8-16 UNC before starting the tap, and apply an appropriate cutting fluid for the workpiece material. Secure the tap in a proper tap handle or machine holder and maintain axial alignment to avoid tap breakage. For blind holes, use a plug or taper tap to start the thread before finishing with this bottoming tap.