Hertel K008438AS Straight Flute Tap 3/8-16 Unc Hss

Product Description

The HERTEL K008438AS is a straight flute tap designed for cutting 3/8-16 UNC internal threads in a wide range of workpiece materials. Built from high speed steel with a bright uncoated finish, this tap delivers reliable thread formation in through-hole and blind-hole applications where chip evacuation is manageable by hand or machine. The plug chamfer — spanning approximately 3 to 5 thread leads — makes it equally suited for starting a thread and completing it in most standard production environments. With an overall length of 2-15/16 inches and a 4-flute configuration, it fits standard tap holders and is the go-to choice for machinists running moderate-volume threading operations.

This tap is used in machine shops, maintenance and repair operations, and light manufacturing settings where 3/8-16 UNC fastener threads are required. The 2B class of fit is the standard commercial tolerance for general-purpose inch fasteners, making this tap appropriate for the vast majority of nut, bolt, and stud thread applications. The H5 thread limit indicates a tighter ground tolerance, useful when consistent fit across a production run is required. It is installed by machinists and toolroom technicians using standard tap wrenches, tapping heads, or CNC rigid-tap cycles.

Key Features

• 3/8-16 UNC thread form, 2B class of fit for general-purpose commercial thread tolerance
• H5 thread limit for consistent, repeatable fit across production volumes
• Plug chamfer (approximately 3-5 lead threads) for versatile through-hole and blind-hole use
• 4 straight flutes — chips fall away or are cleared manually, suitable for shorter chipping materials
• High speed steel construction withstands moderate cutting speeds and intermittent heat
• Bright uncoated finish — ready to use as-received, no coating compatibility concerns

Compatibility

Designed as a standard replacement or production tap for any application requiring a 3/8-16 UNC, 2B class of fit, plug-chamfer straight flute tap. Fits standard 3/8-inch tap holders and tapping chucks used in manual and CNC machine tool setups.

Installation Notes

This tap is installed by qualified machinists or toolroom technicians. Secure the tap in a properly sized tap holder or tapping chuck before use, and ensure the spindle is powered down before changing tooling. Apply cutting fluid appropriate to the workpiece material to extend tool life and improve thread finish. Straight flute taps are best suited for shorter chipping materials such as cast iron, brass, and free-machining steel — use spiral flute taps for longer chipping materials where chip evacuation is a concern.