Osg 2906008 Spiral Flute Tap 3-48 Unc Ticn Vanadium Hss

Product Description

The OSG 2906008 is a spiral flute tap designed for cutting 3-48 UNC internal threads in a wide range of metallic workpiece materials. It features a 45-degree helix angle that actively evacuates chips up and out of the hole, reducing the risk of chip packing in blind-hole applications. The tap is manufactured from vanadium high-speed steel and finished with a titanium carbonitride (TiCN) coating for improved hardness, lubricity, and wear resistance. With a modified bottoming chamfer and a 2B class of fit, this tap threads close to the bottom of a blind hole while producing threads within standard tolerance limits. Overall length is 3.375 inches with a thread length of 0.496 inches.

This tap is suited for threading 3-48 UNC holes in alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel workpieces. The modified bottoming chamfer makes it appropriate for blind holes where full thread depth is needed close to the base. It is commonly used in toolrooms, machine shops, and precision manufacturing environments where small-diameter tapping in tough materials is a routine operation. The right-hand spiral flute geometry and right-hand thread direction are standard for conventional tapping spindles and tap handles.

Key Features

• 45-degree right-hand spiral flute geometry for efficient chip evacuation in blind holes
• TiCN coating increases surface hardness and reduces friction against abrasive workpiece materials
• Modified bottoming chamfer allows threading close to the bottom of a blind bore
• Vanadium high-speed steel substrate provides toughness in interrupted cuts and harder alloys
• 2B class of fit produces threads within standard UNC tolerance range
• H2 thread limit for controlled tap oversize suitable for plated or tight-tolerance applications

Compatibility

Designed for cutting 3-48 UNC right-hand internal threads. Compatible workpiece materials include alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel. Shank diameter is 0.367 inches; verify that the tapping holder or chuck accommodates this shank before use.

Installation Notes

Small-diameter taps should be installed and operated by machinists or toolroom technicians familiar with tapping torque limits for the 3-48 thread size. Use an appropriate cutting fluid or tapping compound rated for the workpiece material to extend tool life and maintain thread quality. Ensure the workpiece is securely fixtured and the tap is properly aligned with the pilot hole before starting the cut. Do not exceed the recommended RPM for the tap size and material combination, as small-diameter taps are susceptible to breakage under excessive torque or misalignment.