Value Collection MSC-04918108 Straight Flute Tap 7/8-9

Product Description

The VALUE COLLECTION MSC-04918108 is a straight flute bottoming tap designed for cutting left-hand internal threads in through holes and blind holes where the thread must extend close to the bottom. Ground from high-speed steel with a bright uncoated finish, this tap is built for use in manual tapping operations and compatible power tapping equipment. It cuts a 7/8-9 UNC thread profile to a 3B class of fit, producing threads that meet standard tolerance requirements for commercial and industrial fastener applications. The H4 thread limit accommodates typical plating allowances and controlled oversize conditions. Licensed machinists and toolroom professionals are the primary users.

This tap is suited for ferrous and non-ferrous materials in job shop, production machining, and maintenance-repair-operations environments. The bottoming chamfer, with only 1-2 lead threads, allows threading to within a few threads of the bottom of a blind hole. The 4-flute straight flute geometry provides good chip support and hole guidance in short-chipping materials such as cast iron, brass, and free-machining steel. It is not designed for coolant-through delivery.

Key Features

• 7/8-9 UNC thread form to 3B class of fit for standard commercial thread tolerance
• Bottoming chamfer for threading close to the bottom of blind holes
• Left-hand thread direction for reverse-thread applications
• 4 straight flutes for stable guidance and chip support in short-chipping materials
• H4 thread limit for controlled oversize and plating allowance
• High-speed steel construction with bright uncoated finish for general-purpose tapping

Compatibility

Designed as a general-purpose OEM-style replacement or standard toolroom tap for manual and machine tapping of 7/8-9 UNC left-hand threads in industrial and maintenance applications.

Installation Notes

This tap should be installed in a standard tap wrench or compatible tapping head rated for the shank size. Always ensure the workpiece is securely fixtured and the tap is properly aligned before cutting begins. Apply appropriate cutting fluid for the workpiece material to extend tool life and improve thread quality. Left-hand taps must be turned counterclockwise to advance; confirm thread direction requirements before use to avoid tool damage or scrap parts.