Value Collection JY4838413 Straight Flute Tap 10-40 Uns

Product Description

The VALUE COLLECTION JY4838413 is a straight flute tap designed for cutting internal threads in applications requiring a 10-40 UNS thread form. Built from high-speed steel (HSS) with a bright, uncoated finish, this tap delivers reliable performance in ferrous and non-ferrous materials. The bottoming chamfer design allows threading close to the bottom of blind holes, making it well suited for tight-tolerance machining work. With 4 flutes and an H2 thread limit, it holds a 3B class of fit and maintains dimensional consistency across production runs. Overall length is 2.375 inches. Right-hand thread direction. Installed by machinists and tool-and-die professionals in manual and CNC tapping operations.

This tap is intended for use in machine shops, manufacturing facilities, and maintenance environments where UNS (Unified National Special) threads are specified. The bottoming chamfer allows the tap to thread nearly to the bottom of a blind hole, which is critical when full thread depth is required within a limited bore depth. It is appropriate for use in light metals, mild steel, and similar workpiece materials where HSS tooling is standard. Typical applications include fixture building, custom fastener work, and repair threading where standard UN series pitches do not apply.

Key Features

• Bottoming chamfer for threading to the bottom of blind holes
• High-speed steel construction for durability in a wide range of workpiece materials
• H2 thread limit ensures tight tolerance control for 3B class of fit
• 4-flute design provides balanced cutting action and chip management
• Bright, uncoated finish suitable for general-purpose tapping applications
• Right-hand thread direction, compatible with standard tapping heads and tap wrenches

Compatibility

Designed as a standard replacement or production tap for applications specifying a 10-40 UNS internal thread with a 3B class of fit in blind or through-hole configurations.

Installation Notes

This tap should be installed and operated by qualified machinists familiar with tapping feeds, speeds, and cutting fluid selection appropriate to the workpiece material. Secure the tap in a properly aligned tap holder or tapping head to prevent cross-threading and tap breakage. Ensure the workpiece is fixtured securely and the pilot hole is drilled to the correct tap drill size before threading. Never force a tap against bottom contact in a blind hole without confirming sufficient chip clearance.