Hertel G837617 Extension Tap 5/16-24 Hss Spiral Point

Product Description

The HERTEL G837617 is a spiral point plug extension tap designed for cutting 5/16-24 UNF right-hand threads in a range of materials. Built from high speed steel with a bright uncoated finish, this tap delivers reliable thread-cutting performance without additional surface treatment. The spiral point geometry pushes chips ahead of the cut, making it well suited for through-hole tapping applications. At 6 inches overall length, the extension design provides additional reach for threading in recessed or hard-to-access locations. The H3 thread limit holds tight tolerance control for 3B class of fit threads. Two flutes and a plug chamfer complete the geometry for general-purpose production tapping.

This tap is intended for use in through-hole tapping operations where standard-length taps cannot reach the workpiece. The 6-inch overall length makes it practical for deep-set bosses, structural components, and assemblies where the thread entry point is set back from the workpiece face. Machinists and tool-and-die professionals working in job shops, maintenance facilities, and production environments are the primary users. The 5/16-24 UNF thread size and reduced shank design allow use in standard tap holders and extension tooling setups.

Key Features

• Spiral point geometry pushes chips forward, optimized for through-hole tapping
• H3 thread limit for 3B class of fit tolerance control
• 6-inch overall length provides extended reach into recessed bores
• High speed steel construction for general-purpose thread cutting
• Bright uncoated finish suitable for use with cutting fluids across a range of workpiece materials
• Reduced shank design compatible with standard tap holders and extension tooling

Compatibility

Designed as a standard extension tap for through-hole applications requiring 5/16-24 UNF right-hand threads with a 3B class of fit.

Installation Notes

This tap is installed and operated by machinists using standard tapping equipment, including drill presses, CNC machining centers, or hand tap wrenches with appropriate extension holders. Secure the workpiece before tapping and ensure the pilot hole diameter matches the 5/16-24 UNF tap drill specification. Use an appropriate cutting fluid for the workpiece material to extend tap life and improve thread quality. Inspect the tap for wear or chipping before each use and never force a tap that has stalled in the hole.