Value Collection MSC-04910212 Straight Flute Tap 1/4-20 Unc

Product Description

The VALUE COLLECTION MSC-04910212 is a straight flute tap designed for cutting internal threads in pre-drilled holes. Made from high-speed steel with a bright, uncoated finish, this tap produces 1/4-20 UNC threads to a 3B class of fit with an H3 thread limit. The bottoming chamfer geometry allows threading close to the bottom of blind holes, making it well suited for tight-tolerance work. The left-hand thread direction is critical to note before installation. Thread length is 1 inch and overall length is 2.5 inches. Licensed machinists, tool-and-die makers, and maintenance technicians use this tap with standard tapping equipment.

This tap is used in general machining, maintenance, and repair applications where 1/4-20 UNC left-hand internal threads are required. The bottoming chamfer style is appropriate for blind-hole applications where a plug or taper tap cannot reach full thread depth. Typical materials tapped include mild steel, aluminum, and similar workpiece materials suited to HSS tooling. It is sold individually and is a standard catalog cutting tool for job shops, production floors, and field maintenance use.

Key Features

• 1/4-20 UNC thread form with 3B class of fit and H3 thread limit for consistent tolerance control
• Bottoming chamfer allows threading to the bottom of blind holes
• Left-hand thread direction for left-hand threaded fastener applications
• 4-flute straight flute design for use in through holes and shallow blind holes
• High-speed steel construction provides durability across common workpiece materials
• Bright, uncoated finish suits general-purpose tapping without specialized coolant requirements

Compatibility

Designed as a standard-style replacement or working tap for applications requiring 1/4-20 UNC left-hand internal threads. Compatible with standard tap wrenches, T-handle tap wrenches, and tapping attachments that accept this shank size.

Installation Notes

This tap is installed by machinists and maintenance technicians using hand or machine tapping equipment. Ensure the pre-drilled hole is sized to the correct tap drill diameter for 1/4-20 UNC threads before starting. Apply appropriate cutting fluid to extend tool life and improve thread quality. Because this is a left-hand tap, rotation direction is reversed from standard right-hand tapping practice.