Accupro T1620643 Spiral Point Tap 5/8-11 Plug Vanadium Hss

Product Description

The ACCUPRO T1620643 is a spiral point tap designed for cutting 5/8-11 UNC internal threads in through-hole applications. Built from 3% vanadium high speed steel with an oxide finish, it delivers improved wear resistance and lubricity compared to standard HSS taps. The plug chamfer (4-5 thread lead) provides a gradual thread-forming entry, making it well-suited for machine tapping operations. With 3 flutes and a right-hand thread direction, the tap pushes chips forward ahead of the cutting zone, reducing the risk of chip packing in through holes. It carries a Class 3B fit and H3 thread limit for close-tolerance threading applications.

This tap is intended for production tapping of through holes in stainless steel and other tough ferrous materials. The 3% vanadium HSS composition gives it added toughness and hot hardness for use in materials that generate high cutting temperatures. It is appropriate for use in CNC machining centers, drill presses, and tapping heads where controlled feed and speed can be maintained. The oxide finish provides a mild level of surface protection and break-in lubricity during initial cuts.

Key Features

• 5/8-11 UNC thread form with right-hand cutting direction
• 3% vanadium high speed steel for improved toughness in stainless steel and hard alloys
• Plug chamfer for gradual thread entry in through-hole tapping
• 3 flutes with spiral point geometry to push chips forward and prevent packing
• H3 thread limit and Class 3B fit for close-tolerance applications
• Oxide finish for surface protection and reduced galling during initial use

Compatibility

Designed for through-hole tapping of stainless steel workpieces. The H3 thread limit and 3B class of fit make it compatible with standard 5/8-11 UNC threaded fastener assemblies requiring close tolerances.

Installation Notes

This tap should be installed by a machinist or tooling technician in a rigid tapping setup or CNC machine with synchronous feed capability. Always ensure the spindle is fully stopped and the machine is in a safe state before changing or inspecting taps. Use a suitable cutting fluid or tapping compound rated for stainless steel to extend tool life and maintain thread quality. Follow applicable shop safety procedures and machine manufacturer guidelines for tool holding torque and runout limits.