Value Collection JY4876991 Straight Flute Tap 1-3/4-5 Unc

Product Description

The VALUE COLLECTION JY4876991 is a straight flute tap designed for cutting 1-3/4-5 UNC internal threads in a range of workpiece materials. With 6 flutes and a plug chamfer, it starts threads partway into a hole rather than at the very edge, making it well suited for through-hole and semi-blind threading operations. Manufactured from high-speed steel with a bright, uncoated finish, the tap delivers consistent cutting performance across steel, cast iron, aluminum, and similar materials. Overall length is 7 inches. Machinists, tool-and-die makers, and maintenance technicians use this tap in manual tapping operations and low-speed machine tapping setups.

This tap is used in industrial, manufacturing, and maintenance-repair-overhaul (MRO) environments where large-diameter UNC threads are required. The 1-3/4-5 UNC thread form is common in heavy equipment, structural fastener applications, and large mechanical assemblies. The plug chamfer style makes it a general-purpose choice when threads can be started with moderate lead-in length. Right-hand thread direction is standard for the overwhelming majority of threading applications. The H4 thread limit indicates an oversize tolerance that accommodates plated fasteners and provides reliable thread fit to the 3B class of fit specification.

Key Features

• 1-3/4-5 UNC thread form for large-diameter unified coarse-thread applications
• 6 flutes provide good chip distribution and stable cutting action at this diameter
• Plug chamfer (3-5 thread lead-in) suits through-hole and open-ended blind-hole threading
• H4 thread limit designed for use with plated fasteners or where a slightly looser 3B fit is needed
• High-speed steel construction withstands the heat and torque demands of large-diameter tapping
• Bright uncoated finish — no coating buildup to affect thread tolerance; easy to inspect for wear
• Right-hand thread direction, 7 inches overall length for clearance in deep setups

Compatibility

Designed as a standard replacement or stock tap for any manual or machine tapping setup requiring a 1-3/4-5 UNC plug-style tap with a 3B class of fit and H4 thread limit.

Installation Notes

Tapping at this diameter generates significant torque — use a rigid tapping setup or a torque-limiting tap wrench to reduce the risk of tap breakage. Always apply appropriate cutting fluid for the workpiece material and clear chips frequently, especially in deeper holes. Secure the workpiece firmly before starting. Inspect the tap for chipping or wear before each use; a dull or damaged tap at this size can seize in the hole and be extremely difficult to remove.