Import BDNA-20679 Tap Set 1/4-28 Unf Hss Gold Oxide 3 Pc

Product Description

The IMPORT BDNA-20679 is a 3-piece tap set designed for cutting 1/4-28 UNF internal threads in metal workpieces. The set includes bottoming, plug, and taper chamfer taps, allowing machinists and maintenance technicians to start, advance, and finish threads in a single coordinated progression. Each tap is ground from high-speed steel (HSS) and carries a gold oxide finish that provides light lubricity and corrosion resistance during cutting. Overall length is 2.5 inches. The 4-flute geometry offers good chip clearance and thread quality in a range of ferrous and non-ferrous materials. This set is appropriate for hand tapping and compatible machine tapping operations in shop, field, or maintenance environments.

This tap set is suited for threading operations in light-gauge steel, aluminum, and similar materials where a 1/4-28 UNF fine-thread form is required. Typical applications include HVAC equipment assembly, electrical enclosure hardware repair, plumbing fixture work, and general mechanical maintenance. The inclusion of all three chamfer styles makes the set practical for both through-holes and blind holes. The H3 thread limit designation indicates a tolerance class appropriate for standard fit mating fasteners in general industrial and trade service work.

Key Features

• 3-piece set includes bottoming, plug, and taper taps for complete threading in one kit
• 1/4-28 UNF thread form with H3 thread limit for standard tolerance fits
• High-speed steel construction for durability in ferrous and non-ferrous materials
• 4-flute design promotes chip evacuation and clean thread form
• Gold oxide finish adds light lubricity and mild corrosion protection
• 2.5-inch overall length fits standard tap wrenches and tap holders

Compatibility

Designed for cutting 1/4-28 UNF internal threads per Unified National Fine thread standards. Suitable for use with standard tap wrenches, T-handles, and machine tap holders accepting the corresponding shank size.

Installation Notes

Thread cutting should be performed by a qualified machinist or maintenance technician familiar with hand or machine tapping procedures. Always use an appropriate cutting fluid for the base material to extend tap life and improve thread quality. Secure the workpiece firmly before tapping and back the tap off periodically to break chips, particularly in blind holes. Inspect tap flutes for wear or damage before each use to avoid tap breakage.