Value Collection JY4879995 Hand Tap 2-1/4-4-1/2 Unc

Product Description

The VALUE COLLECTION JY4879995 is a straight-flute hand tap designed for cutting 2-1/4-4-1/2 UNC internal threads in a wide range of materials. Built from bright, uncoated high speed steel, this tap offers the hardness and edge retention needed for threading operations in ferrous and non-ferrous metals. The plug chamfer — typically 3 to 5 threads of lead — makes it well suited for through-hole tapping where the tap can enter the hole with moderate starting torque. With 6 flutes, it provides additional cutting edges and improved thread finish compared to lower-flute-count designs. Overall length is 8.25 inches. Class of fit is 3B with a thread limit of H7.

This tap is intended for use in heavy-duty manual or low-speed machine tapping applications where large-diameter UNC threads are required. The 2-1/4-4-1/2 UNC designation is a coarse-pitch thread commonly found in structural fasteners, heavy equipment assemblies, large pipe flanges, and industrial machinery. It is typically installed by machinists, millwrights, and maintenance technicians working on large-format metal components. The right-hand thread direction follows standard convention for the majority of fastener applications in industrial and manufacturing environments.

Key Features

• 2-1/4-4-1/2 UNC thread form, right-hand direction
• Plug chamfer with 3 to 5 thread lead for through-hole tapping
• High speed steel construction for hardness and wear resistance
• Bright uncoated finish suitable for general-purpose threading
• 6-flute design for improved cutting performance and thread surface quality
• Class 3B fit with H7 thread limit for consistent tolerance control

Compatibility

Designed as a general-purpose hand tap for cutting 2-1/4-4-1/2 UNC Class 3B internal threads in through-hole applications across industrial and manufacturing settings.

Installation Notes

This tap should be installed and operated by a qualified machinist or maintenance technician. Before tapping, ensure the workpiece is securely fixtured and the pilot hole is drilled to the correct tap drill diameter for a 2-1/4-4-1/2 UNC thread. Apply appropriate cutting fluid throughout the tapping operation to reduce heat and extend tool life. Back off the tap periodically to break chips and prevent binding, especially in deeper holes.