Osg 2942101 Spiral Flute Tap 3/8-16 Unc Vanadium Hss

Product Description

The OSG 2942101 is a spiral flute tap designed for cutting right-hand internal threads in a 3/8-16 UNC configuration. Built from 3% Vanadium High-Speed Steel (HSS) and finished with a steam oxide coating, this tap handles demanding tapping applications where chip evacuation is critical. The spiral flute geometry pulls chips up and out of the hole, making it well-suited for blind-hole threading. The modified bottoming chamfer allows threading closer to the bottom of a blind bore compared to a standard plug or taper chamfer. Overall length is 2-15/16 inches with a 45-degree helix angle for smooth, controlled chip flow. Thread limit is H7, indicating a slight oversize grind for plated-fastener or tight-tolerance thread fits.

This tap is rated for use in alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel. It is well-suited for machine tapping in CNC machining centers, drill presses, and tapping heads where consistent thread quality across production runs is required. The steam oxide finish provides a degree of lubricity and corrosion resistance that extends tool life in ferrous materials. Series 290 taps from OSG are a common choice in job shops and production environments handling general-purpose ferrous threading tasks.

Key Features

• Spiral flute design evacuates chips upward, ideal for blind-hole tapping applications
• Modified bottoming chamfer threads closer to the bottom of a blind bore than plug or taper styles
• 3% Vanadium HSS construction provides increased wear resistance over standard M2 HSS
• Steam oxide coating adds lubricity and reduces built-up edge in ferrous materials
• H7 thread limit provides oversize compensation for plated or close-tolerance thread fits
• 45-degree helix angle promotes controlled chip flow and reduced tapping torque

Compatibility

Rated for use in alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel. Designed for 3/8-16 UNC right-hand thread applications in machine tapping setups.

Installation Notes

This tap is intended for installation by machinists and tooling professionals using a tapping head, CNC machine, or drill press with proper tapping attachments. Always ensure the spindle speed and feed rate are appropriate for the workpiece material before engaging the tap. Use a cutting fluid or tapping compound rated for the specific workpiece material to extend tool life and maintain thread quality. Inspect the tap for wear or chipping before each use and replace at the first sign of thread quality degradation.