Value Collection JY4877007 Hand Tap 1-3/4-5 Unc Bottoming Hss

Product Description

The VALUE COLLECTION JY4877007 is a bottoming hand tap designed for cutting internal threads in through-holes and blind holes where full thread depth is required close to the bottom. Ground from high speed steel (HSS) with a bright, uncoated finish, this tap runs a 1-3/4-5 UNC thread form with a 6-flute straight flute configuration and a right-hand thread direction. At 7 inches overall length, it provides the reach and rigidity required for large-diameter tapping operations in metalworking and machining environments. The H4 thread limit and Class 3B fit designation make it suitable for close-tolerance threading applications where precise fit is critical.

This tap is used in machine shops, maintenance and repair operations, and heavy fabrication settings where large-diameter UNC threads are required. The bottoming chamfer — typically 1 to 2 threads of lead — allows the tap to cut threads to the bottom of a blind hole, making it the final step in a standard tap progression following a taper or plug tap. It is handled by machinists and tool-and-die professionals working in ferrous and non-ferrous materials. Applications include fabrication of large fastener holes, repair of damaged threads, and production threading of structural components.

Key Features

• Bottoming chamfer for threading to the bottom of blind holes
• 1-3/4-5 UNC thread form with Class 3B fit and H4 thread limit for close-tolerance applications
• 6-flute straight flute design for increased strength and thread contact in large-diameter tapping
• High speed steel construction for durability across a range of workpiece materials
• Bright, uncoated finish — no coolant-through feature, suitable for manual and low-speed machine tapping
• Right-hand thread direction, 7 inches overall length

Compatibility

Designed for use in standard tap handles and tapping fixtures sized for large-diameter taps; compatible with 1-3/4-5 UNC thread applications in metalworking, repair, and fabrication operations.

Installation Notes

This tap is installed and operated by machinists using appropriately sized tap wrenches or tapping heads rated for large-diameter work. Secure the workpiece and ensure the tap is started square to the hole to prevent thread damage or tool breakage. Apply cutting fluid appropriate to the workpiece material throughout the tapping operation. Follow standard shop safety practices and applicable OSHA guidelines when operating cutting tools.