Value Collection JY4862173 Hand Tap 1-1/8-18 Unef

Product Description

The VALUE COLLECTION JY4862173 is a straight-flute hand tap designed for cutting 1-1/8-18 Unified Extra Fine (UNEF) internal threads in ferrous and non-ferrous workpieces. Built from high speed steel (HSS) with a bright, uncoated finish, this tap delivers consistent thread form on the bench or in a drill press at moderate cutting speeds. The plug chamfer — 3 to 5 threads of lead — makes it the standard choice for through-holes and for starting threads in blind holes that have adequate depth. Six flutes provide good chip clearance and even cutting pressure across the thread profile. Overall length is 4 inches, and the H4 thread limit controls oversize tolerance for close-tolerance Class 3B fits.

This tap is suited for maintenance shops, toolrooms, and production environments where UNEF threads are required on larger-diameter fastener applications. The 1-1/8-18 UNEF designation is common in precision assemblies, aerospace-adjacent work, and hydraulic fittings where a finer pitch than UNC or UNF is specified. Right-hand threading direction is standard. It is installed by hand with a tap wrench or a tapping fixture and does not require coolant-through tooling, making it compatible with manual or light CNC tapping operations where flood or mist coolant is applied externally.

Key Features

• 1-1/8-18 UNEF thread form — extra-fine pitch for precise thread engagement
• Plug chamfer provides 3-5 threads of lead for easy starting in through-holes or deep blind holes
• 6-flute geometry distributes cutting load and improves chip evacuation
• High speed steel construction handles a broad range of workpiece materials
• Bright uncoated finish — suitable for use with cutting oil or coolant
• Class 3B fit with H4 thread limit for tight-tolerance thread applications

Compatibility

Designed as a standard hand tap for cutting 1-1/8-18 UNEF Class 3B internal threads in accordance with Unified thread standards. Fits standard tap wrench collets and tapping heads sized for the tap shank associated with 1-1/8-inch diameter taps.

Installation Notes

This tap is installed by a machinist or toolroom technician using a proper-size tap wrench or tapping fixture — never drive with an impact tool. Secure the workpiece before starting and apply cutting oil or appropriate tapping fluid throughout the operation. Back the tap off periodically to break and clear chips, especially in blind-hole applications. Inspect the tap for chipping or wear before each use; a damaged tap run under load can break and seize in the workpiece.