Hertel G859442 Extension Tap M5 X 0.8 Hss Spiral Point

Product Description

The HERTEL G859442 is an extension tap designed for cutting M5 x 0.8 metric coarse internal threads in a wide range of materials. Built from high speed steel, this spiral point plug tap drives chips forward ahead of the cutting edge, making it well suited for through-hole tapping operations. The tap measures 6 inches in overall length, which provides added reach in deep or obstructed workpiece locations. With a D4 thread limit and a 6H class of fit, it produces threads within the standard tolerance range required for most general-purpose metric fastener assemblies. Licensed machinists and toolroom technicians are the typical installers.

This tap is used in production machining, maintenance and repair operations, and toolroom work where metric coarse threads are required. The spiral point geometry makes it especially effective in through-hole applications where chip clearance is a priority. The reduced shank design allows the tap to be used in applications where standard shank diameter would limit access or require a larger collet or chuck. Right-hand flute direction is consistent with standard right-hand thread cutting.

Key Features

• M5 x 0.8 metric coarse thread form for standard metric fastener compatibility
• Spiral point geometry drives chips forward, reducing chip packing in through-hole applications
• High speed steel construction provides durability across a broad range of workpiece materials
• D4 thread limit with 6H class of fit meets general-purpose metric tolerance requirements
• 6-inch overall length provides extended reach for deep or restricted access holes
• Reduced shank allows use in smaller collets and chuck configurations

Compatibility

Designed as an OEM-style extension tap for through-hole tapping of M5 x 0.8 metric coarse threads in standard machining and maintenance applications.

Installation Notes

This tap is installed and operated by machinists, toolroom technicians, or maintenance professionals using a tap wrench, tapping attachment, or CNC machine spindle with appropriate tap holder. Before beginning, secure the workpiece and confirm the pilot hole diameter matches the M5 x 0.8 thread specification. Use appropriate cutting fluid for the workpiece material to extend tap life and improve thread finish. Never force a tap against resistance, as high speed steel is brittle and will break under excessive torque.