Value Collection MSC-04609459 Spiral Flute Tap 4-40 Unc

Product Description

The VALUE COLLECTION MSC-04609459 is a spiral flute tap designed for cutting 4-40 UNC internal threads in blind holes where a bottoming chamfer is required. Manufactured from high-speed steel with a bright, uncoated finish, it features a 45-degree helix angle and a fast flute style that evacuates chips upward out of the hole during the tapping operation. The 2-flute geometry suits applications where chip clearance space is limited. At 1.875 inches overall length, this tap fits standard tap handles and machine tool holders used in precision machining, maintenance, and fabrication work.

This tap is suited for threading 4-40 UNC holes in ferrous and non-ferrous materials in production and jobsite environments. The bottoming chamfer allows threads to be cut to within 1-2 threads of the bottom of a blind hole, making it the correct choice when full thread depth close to the hole bottom is required. It carries a 2B/3B class of fit, covering the standard range of tolerance classes used in general mechanical assembly and close-tolerance fastener applications. Right-hand thread direction is standard for conventional 4-40 UNC fastener systems.

Key Features

• Bottoming chamfer for maximum thread depth in blind holes
• 45-degree helix angle with fast flute style for efficient chip evacuation
• H2 thread limit for 2B/3B class of fit tolerance control
• High-speed steel construction for durability across ferrous and non-ferrous materials
• Bright/uncoated finish — no additional coating buildup on thread form
• Right-hand spiral flute direction matches standard right-hand thread cutting

Compatibility

Designed for use in standard tap handles, T-handle wrenches, and machine tool tap holders sized for 4-40 UNC taps. Compatible with applications requiring 2B or 3B class of fit internal threads per UNC thread standards.

Installation Notes

Secure the workpiece fully before tapping to prevent movement during thread cutting. Apply an appropriate cutting fluid for the material being tapped to extend tool life and improve thread finish. Do not force the tap if resistance increases sharply — back off to break the chip before continuing. Blind hole depth should be drilled to accommodate the tap's non-cutting lead geometry when full thread depth to the bottom is required.