Hertel K008096AS Spiral Flute Tap 4-40 Unc Bottoming Hss

Product Description

The HERTEL K008096AS is a spiral flute bottoming tap designed for threading 4-40 UNC holes in a wide range of materials. Built from high-speed steel, this tap features a 52-degree helix angle with a fast flute style that efficiently evacuates chips upward out of blind holes. It produces a right-hand thread and is rated for a 2B/3B class of fit, making it suitable for both standard and close-tolerance fastener applications. At 1-7/8 inches overall length with 2 flutes and a bottoming chamfer, it is engineered to cut threads as close to the bottom of a blind hole as possible. Machinists and tool-and-die technicians are the primary users.

This tap is suited for use in production machining, maintenance and repair, and toolroom environments where 4-40 UNC threads must be tapped to the full depth of a blind hole. The bottoming chamfer has only 1 to 2 thread leads of relief, allowing threading to within one to two pitches of the hole bottom. It is commonly used in light sheet metal, precision instrument work, electronic enclosures, and small mechanical assemblies where the 4-40 thread standard is the specified fastener size.

Key Features

• Bottoming chamfer for threading to the bottom of blind holes
• 52-degree helix angle with fast flute style for efficient upward chip evacuation
• High-speed steel construction for general-purpose tapping performance
• 2B/3B class of fit for standard and close-tolerance thread applications
• Right-hand thread direction, compatible with standard tapping equipment
• H2 thread limit for controlled tap oversize and consistent fit

Compatibility

Designed as an OEM-style threading tool for use in any machine or hand-tapping application requiring a 4-40 UNC bottoming tap with a right-hand, 2-flute spiral flute configuration.

Installation Notes

Installation and use should be performed by qualified machinists following standard shop safety practices. Ensure the workpiece is securely clamped and the tap is properly aligned to the drilled pilot hole before applying torque. Power down or disengage the tapping head before changing or inspecting taps. Use appropriate cutting fluid for the workpiece material to extend tap life and reduce the risk of breakage.