Value Collection MSC-04471256 Straight Flute Tap 5/16-24 Unf

Product Description

The VALUE COLLECTION MSC-04471256 is a bottoming straight flute tap designed for cutting internal threads in through-holes and blind holes where full thread depth is required close to the bottom. Built from high-speed steel (HSS) with a bright, uncoated finish, this tap handles 5/16-24 UNF right-hand threads and features four flutes for efficient chip evacuation during manual or machine tapping operations. It carries an H3 thread limit and a 3B class of fit, making it appropriate for standard tolerance threaded assemblies. Machinists and maintenance technicians reach for this style of tap when thread engagement at the base of a blind hole is critical to joint integrity.

This tap is suited for threading steel, aluminum, and similar materials in production machining, toolroom, and MRO maintenance environments. The bottoming chamfer — typically 1 to 2 threads of lead — allows threads to be cut to within one or two pitches of a blind hole bottom. It is commonly used in machine shops, metal fabrication facilities, and industrial maintenance settings where 5/16-24 UNF fastener compatibility is required. The 1-1/8 inch thread length and 2-23/32 inch overall length fit standard tap handles and tapping heads in this size range.

Key Features

• Bottoming chamfer allows full thread depth in blind holes with minimal runout at the bottom
• 5/16-24 UNF thread form for fine-pitch unified national thread applications
• High-speed steel construction provides wear resistance across a broad range of workpiece materials
• H3 thread limit and 3B class of fit for standard tolerance threaded connections
• Four straight flutes support chip flow and cutting stability during tapping
• Bright uncoated finish — no coating interference on close-tolerance applications

Compatibility

Designed as a standard 5/16-24 UNF bottoming tap compatible with conventional tap wrenches, T-handles, and machine tapping chucks sized for the shank diameter of a 5/16 inch tap.

Installation Notes

This tap is installed by machinists and maintenance technicians using hand tap wrenches or tapping attachments on drill presses and milling machines. Always use cutting fluid appropriate for the workpiece material to extend tool life and improve thread finish. Ensure the hole is drilled to the correct tap drill diameter for 5/16-24 UNF before tapping. Avoid reversing the tap under load without backing off periodically to break chips and prevent tap breakage in blind holes.