Value Collection JY4879037 Hand Tap 2-8 Uns Bottoming Hss

Product Description

The VALUE COLLECTION JY4879037 is a bottoming hand tap designed for cutting 2-8 UNS internal threads in a variety of workpiece materials. Built from high speed steel (HSS) with a bright uncoated finish, this tap delivers consistent thread form and dimensional accuracy when used in manual tapping operations. The 6-flute straight flute geometry provides even cutting action and good chip evacuation in through-hole and blind-hole applications. At 7.625 inches overall length with a 3.5625-inch thread length, it handles moderate to deep thread engagements common in industrial maintenance and fabrication work. The H6 thread limit designates a specific tolerance class suited to close-tolerance threading requirements. Machinists, toolmakers, and maintenance technicians are the primary users of this tool.

This tap is used wherever 2-8 UNS bottoming threads are required, including heavy-duty fastener applications, repair threading of worn bores, and production threading of large-diameter parts. The bottoming chamfer — typically 1 to 2 threads of lead — allows threading to the full depth of blind holes after a taper or plug tap has started the thread. It is appropriate for use in machine shops, MRO environments, and field maintenance settings where manual tapping of large coarse threads is required.

Key Features

• 2-8 UNS thread form for large-diameter unified national special thread applications
• Bottoming chamfer for threading to the bottom of blind holes
• 6-flute straight flute design promotes even cutting load distribution
• High speed steel construction for durability across a range of workpiece materials
• Bright uncoated finish — no coating buildup affects thread tolerance
• H6 thread limit for close-tolerance thread production

Compatibility

Designed as an OEM-style hand tap for cutting 2-8 UNS right-hand internal threads. Intended for use with standard tap wrenches or T-handles sized to accommodate large-diameter hand taps of this shank class.

Installation Notes

This tap is installed by a machinist or maintenance technician using a manual tap wrench. Ensure the workpiece is securely fixtured and the tap is started square to the hole axis to prevent thread distortion or tap breakage. Apply cutting fluid rated for the workpiece material throughout the tapping operation, and back off the tap periodically to break chips. Do not apply excessive force — large HSS taps can fracture under lateral load if the tap binds in the bore.