Value Collection MSC-04918165 Straight Flute Tap 7/8-14 Unf

Product Description

The VALUE COLLECTION MSC-04918165 is a straight flute tap designed to cut internal left-hand threads in ferrous and non-ferrous materials. Built from high-speed steel with a bright/uncoated finish, it produces 7/8-14 UNF threads to a 3B class of fit, making it suitable for applications requiring precise thread tolerance. The taper chamfer distributes cutting load gradually across multiple teeth, reducing tap breakage in through-hole and deep-hole applications. With 4 flutes and an H4 thread limit, this tap is well suited for hand tapping and machine tapping operations where chip clearance and dimensional accuracy are priorities. Licensed machinists, toolroom technicians, and maintenance mechanics are the typical users.

This tap is used in production and maintenance environments where left-hand thread fastening is required, such as assemblies that must resist loosening under counterclockwise rotation. The 7/8-14 UNF thread form applies to medium-to-large diameter fine-pitch applications common in automotive, aerospace, and industrial machinery repair. The taper chamfer entry makes it particularly practical for starting threads in blind or through holes by hand or with a tapping head on a drill press or CNC machine. The 3B class of fit indicates a standard tolerance range compatible with commercial-grade mating fasteners.

Key Features

• 7/8-14 UNF left-hand thread form with 3B class of fit for standard commercial tolerance
• Taper chamfer distributes cutting force gradually, reducing breakage risk on entry
• 4 straight flutes provide adequate chip clearance in through-hole and moderate-depth blind-hole applications
• High-speed steel construction offers good toughness and wear resistance across a range of workpiece materials
• H4 thread limit provides controlled oversize tolerance for use with standard thread gauges
• Bright/uncoated finish suitable for use with cutting fluid in most general-purpose tapping operations

Compatibility

Designed as an OEM-style replacement or standard toolroom tap for any application requiring a 7/8-14 UNF left-hand internal thread. Compatible with standard tap holders, tapping heads, and drill press chucks sized for the tap shank.

Installation Notes

This tap is installed by a machinist or toolroom technician using a tap wrench, tapping head, or CNC tapping cycle. Always apply appropriate cutting fluid for the workpiece material and back off the tap regularly to break chips when tapping by hand. Ensure the workpiece is securely fixtured and the tap is started perpendicular to the hole to prevent thread misalignment or tap breakage. Verify correct drill size for a 7/8-14 UNF thread using a standard tap drill chart before beginning the operation.