Value Collection JY4844411 Straight Flute Tap 1/2-40 Uns

Product Description

The VALUE COLLECTION JY4844411 is a straight flute tap designed to cut internal threads in through-holes and blind holes where a bottoming chamfer is required. Built from high-speed steel with a bright, uncoated finish, this tap produces 1/2-40 UNS right-hand threads to a 3B class of fit with an H3 thread limit. With 4 flutes and a bottoming chamfer, it threads close to the bottom of a blind hole, making it well suited for tight-tolerance fastener applications in metalworking and machining environments. The overall length is 3.375 inches. Machinists and tool-and-die technicians use this tap in manual and CNC tapping operations.

This tap is intended for use in materials where high-speed steel provides adequate hardness and wear resistance. The UNS (Unified National Special) thread form at 1/2-40 covers specialty thread pitches not found in standard UNC or UNF series, often appearing in precision instruments, optical equipment, and custom mechanical assemblies. The bottoming chamfer allows threading to within one to two thread pitches of a blind hole bottom, which is critical when thread engagement depth is limited by part geometry. A separate plug or taper tap is typically used first to start the thread before finishing with this bottoming tap.

Key Features

• Bottoming chamfer for threading close to the bottom of blind holes
• 1/2-40 UNS thread form covers specialty pitch requirements outside standard UNC and UNF series
• 4 straight flutes for chip clearance in through-hole and short blind-hole applications
• 3B class of fit with H3 thread limit for consistent, controlled tolerance threading
• High-speed steel construction provides hardness suitable for a wide range of metals
• Bright, uncoated finish maintains dimensional accuracy without coating thickness variation

Compatibility

Designed as an OEM-style straight flute bottoming tap for use in standard tap holders, T-handle tap wrenches, and CNC tapping chucks accepting round-shank taps sized for 1/2-inch thread work.

Installation Notes

This tap is installed and operated by a machinist or toolmaker using appropriate tap holders or wrenches. Always secure the workpiece and ensure proper alignment before starting the thread to prevent tap breakage. Apply cutting fluid appropriate to the workpiece material to extend tool life and improve thread finish. When tapping blind holes, use a plug or taper tap first, then finish with this bottoming tap to achieve full thread depth.