Value Collection JY4848107 Hand Tap 7/8-16 Uns Bottoming Hss

Product Description

The VALUE COLLECTION JY4848107 is a bottoming hand tap designed for cutting internal threads in through-holes and blind holes where full thread engagement close to the bottom is required. Ground from high speed steel (HSS) and left in a bright, uncoated finish, this tap runs at conventional hand-tapping speeds and holds up well against the abrasion of threading steel, cast iron, aluminum, and similar workpiece materials. The 7/8-16 UNS thread form is cut with four straight flutes that channel chips out of the hole during the tapping operation. Overall length is 4-11/16 inches, providing adequate shank for standard tap wrenches and driver adapters.

This tap is suited for job shop, maintenance and repair, and production environments where 7/8-16 UNS threads must be tapped by hand or with a low-speed tapping attachment. Bottoming chamfer geometry — typically 1 to 2 threads of chamfer — allows the tap to complete threading within a few thread pitches of the hole bottom. It is appropriate for use in ferrous and non-ferrous metals where a right-hand thread and a 3B class of fit are specified by the engineering drawing or assembly standard. A spiral-point or forming tap is not required for this application profile.

Key Features

• Bottoming chamfer for threading close to the bottom of blind holes
• 7/8-16 UNS thread form with right-hand direction
• High speed steel construction for resistance to heat and wear during hand tapping
• Bright uncoated finish — no coating buildup to affect thread tolerance
• 4-flute straight flute design promotes chip evacuation and tap stability
• H4 thread limit and 3B class of fit for standard tolerance thread production

Compatibility

Designed as an OEM-style replacement or direct-use hand tap for any application requiring a 7/8-16 UNS right-hand bottoming tap with a 3B class of fit and H4 thread limit.

Installation Notes

This tap is installed by machinists, toolroom technicians, and maintenance trades using a standard tap wrench or T-handle driver. Always drill the correct tap drill diameter for a 7/8-16 thread before tapping, and ensure the workpiece is securely fixtured. Apply cutting oil or tapping fluid appropriate to the workpiece material to extend tap life and improve thread finish. Back the tap off periodically to break and clear chips, and never force a tap — hand pressure only to avoid breakage in the hole.