Import BDNA-20714 Straight Flute Tap 7/8-9 Unc Plug Hss

Product Description

The IMPORT BDNA-20714 is a straight flute plug tap designed for cutting right-hand internal threads in through-holes and moderately deep blind holes. Manufactured from high-speed steel with a gold oxide coating, it cuts 7/8-9 UNC threads and carries a thread limit designation of H4, indicating a close-tolerance fit suitable for general industrial threading applications. With 4 flutes and a plug chamfer, this tap provides a balance between cutting ease and thread quality. The overall length measures 4-11/16 inches. Machinists, tool-and-die makers, and maintenance technicians use this tap in manual tap handles or machine tapping operations on ferrous and non-ferrous materials.

This tap is suited for production and maintenance threading operations in industrial, manufacturing, and repair environments. The 7/8-9 UNC thread form is a coarse-pitch standard thread widely used in structural fasteners, heavy equipment, and general machine assembly. The plug chamfer style makes it appropriate for starting threads in through-holes or as a follow-up to a taper tap in blind-hole applications. The gold oxide finish provides modest lubricity and corrosion resistance during use and storage.

Key Features

• 7/8-9 UNC thread form for coarse-pitch internal threading
• Plug chamfer provides versatile starting in through-holes and moderately deep blind holes
• High-speed steel construction for durability across ferrous and non-ferrous materials
• Gold oxide coating improves surface lubricity and reduces built-up edge during cutting
• H4 thread limit for close-tolerance thread fit
• 4 straight flutes for chip clearance in hand and machine tapping

Compatibility

Designed as a standard replacement or toolroom tap for any application requiring right-hand 7/8-9 UNC internal threads. Fits standard tap holders and machine spindles sized for 7/8 inch taps.

Installation Notes

Installation should be performed by a qualified machinist or maintenance technician using the appropriate tap handle, tapping head, or CNC tapping attachment. Always use a compatible cutting fluid or tapping compound for the workpiece material to extend tap life and improve thread quality. Ensure the workpiece is securely fixtured before beginning the threading operation. Back off the tap periodically to break chips and prevent tap breakage, especially in deeper holes.