Kennametal 4131159 Hand Tap 5/8-18 Unf Plug 4-flute Hss

Product Description

The KENNAMETAL 4131159 is a 5/8-18 UNF straight-flute hand tap designed for cutting right-hand internal threads in a range of metalworking applications. Built from high-speed steel (HSS) with a bright, uncoated finish, it delivers consistent thread cutting performance without a coating to interfere with tight tolerances. The plug chamfer provides 3 to 5 lead threads, making it suitable for through-hole tapping or as a follow-up tap in blind-hole sequences. With 4 flutes and a Class 2B fit at Thread Limit H5, this tap produces threads within standard UNF tolerance ranges. Overall length is 3.81 inches with a thread length of 1.813 inches and a shank diameter of 0.48 inches. Licensed machinists, tool and die makers, and maintenance trades are the primary installers.

This tap is intended for use in cast iron and non-ferrous metals, making it a practical choice for general machine shop work, maintenance and repair operations, and production threading tasks. It belongs to Kennametal Series 5305 and 5303, which cover standard straight-flute hand taps across common inch thread sizes. The 5/8-18 UNF thread form is frequently encountered in precision fastener applications, fluid fittings, and mechanical assemblies requiring finer thread pitch than the coarse UNC equivalent.

Key Features

• 5/8-18 UNF right-hand thread form, Class 2B fit at Thread Limit H5
• Plug chamfer with 3 to 5 lead threads for through-hole and sequential blind-hole tapping
• 4-flute straight-flute geometry for balanced chip control in cast iron and non-ferrous metals
• High-speed steel construction with bright uncoated finish for close tolerance work
• 3.81-inch overall length with 1.813-inch thread length and 0.48-inch shank diameter
• No coolant-through requirement — compatible with standard hand tapping and machine tapping setups

Compatibility

Designed as an OEM-style replacement or direct tooling selection for 5/8-18 UNF hand tapping operations in cast iron and non-ferrous metal workpieces. Compatible with standard tap handles and machine tap holders accepting a 0.48-inch shank diameter.

Installation Notes

Hand taps should be installed in a properly sized tap wrench or machine holder before use; ensure the workpiece is securely fixtured and the pilot hole is drilled to the correct tap drill diameter for a 5/8-18 UNF thread. Apply cutting fluid appropriate for the workpiece material to extend tap life and improve thread finish. When tapping blind holes, use a plug tap as a starter and follow with a bottoming tap if full thread depth to the bottom is required. Always reverse the tap periodically to break chips and prevent tap breakage, particularly in cast iron and softer non-ferrous materials.