Kennametal 1542148 Hand Tap 1/4-20 Unc Plug 4-flute Hss

Product Description

The KENNAMETAL 1542148 is a straight-flute hand tap designed for cutting right-hand internal threads in a variety of workpiece materials. This plug-chamfer tap produces 1/4-20 UNC threads and is manufactured from high-speed steel with a bright uncoated finish. It carries a Class 3B fit designation and an H3 thread limit, making it suitable for applications that require close-tolerance threaded holes. The tap features four flutes for efficient chip evacuation and is intended for hand tapping or use in low-speed machine tapping operations. Overall length is 2.5 inches with a thread length of 1 inch, giving technicians and machinists a compact, manageable tool for light to medium tapping work.

This tap is well suited for threading operations in cast iron and non-ferrous metals such as aluminum, brass, and copper alloys. It fits into standard tapping routines in job shops, maintenance and repair operations, and production environments where 1/4-20 UNC fastener holes are required. The plug chamfer, with its moderate lead-in angle, is the most commonly used chamfer style and works well for through-holes and blind holes with adequate clearance below the thread. It belongs to the Kennametal Series 5305 and 5303 tap family.

Key Features

• 1/4-20 UNC thread form with right-hand cutting direction
• Plug chamfer for versatile use in through-holes and blind holes
• High-speed steel construction for durability across ferrous and non-ferrous materials
• Bright uncoated finish compatible with a wide range of cutting fluids
• Class 3B fit and H3 thread limit for close-tolerance threaded holes
• Four straight flutes for consistent chip clearance during tapping

Compatibility

Designed for tapping 1/4-20 UNC Class 3B threads in cast iron and non-ferrous metals. Part of the Kennametal Series 5305 and 5303 tap family. Compatible with standard T-handle tap wrenches and machine tap holders sized for a 0.255-inch shank diameter.

Installation Notes

This tap is installed by a machinist or maintenance technician using a tap wrench or appropriate low-speed tapping attachment. Secure the workpiece firmly before starting the thread to prevent tap breakage. Apply a suitable cutting fluid for the workpiece material throughout the tapping operation. Never use an impact driver or high-torque power tool with a hand tap, as this will likely break the tap in the hole.