Import BDNA-20691 Tap Set 5/8-18 Unf Hss Gold Oxide

Product Description

The IMPORT BDNA-20691 is a 3-piece tap set designed for cutting 5/8-18 UNF internal threads in metal workpieces. The set includes bottoming, plug, and taper chamfer styles, allowing machinists and maintenance technicians to start, progress, and finish threads in through-holes or blind holes with a single kit. All three taps are ground from high-speed steel (HSS) with a gold oxide finish that provides mild lubricity and corrosion resistance. Each tap features 4 flutes for efficient chip evacuation and carries a Thread Limit of H3, suited for standard UNF tolerance fits. Overall length is 3-13/16 inches.

This tap set is used in machine shops, maintenance and repair operations (MRO), and field service environments wherever 5/8-18 UNF threaded holes are required. The three-chamfer configuration makes the set practical for both through-hole and blind-hole applications in steel, cast iron, aluminum, and similar machinable metals. Machinists, tool-and-die workers, and industrial maintenance techs are the primary users of this set.

Key Features

• Three-piece set includes bottoming, plug, and taper chamfer taps for complete thread-cutting workflow
• 5/8-18 UNF thread form for fine-pitch unified national thread applications
• High-speed steel construction provides hardness and wear resistance for production and MRO use
• 4-flute geometry supports efficient chip removal in a range of metals
• H3 thread limit for standard tolerance UNF fits
• Gold oxide finish adds mild lubricity and surface protection

Compatibility

Designed for cutting 5/8-18 UNF internal threads; compatible with standard tap holders, T-handle tap wrenches, and machine tap chucks accepting the tap shank size appropriate for this thread range.

Installation Notes

Secure the workpiece and ensure the correct pilot hole diameter is drilled before tapping — refer to standard UNF tap drill charts for 5/8-18. Use cutting fluid appropriate to the workpiece material to extend tap life and reduce the risk of tap breakage. Begin with the taper tap to align the thread, follow with the plug tap, and finish with the bottoming tap when threading to the bottom of a blind hole. Power down any machine spindle and secure the work holding device before repositioning the tap or changing chamfer style.