Kennametal 1542146 Hand Tap 1/4-20 Unc Bottoming 4-flute Hss

Product Description

The KENNAMETAL 1542146 is a 1/4-20 UNC straight-flute hand tap designed for bottoming applications in cast iron and non-ferrous metals. Manufactured from high-speed steel with a bright uncoated finish, it cuts right-hand threads and is suited for use where full thread depth to the bottom of a blind hole is required. The tap features a 4-flute straight-flute geometry with an H2 thread limit, giving machinists and toolroom technicians predictable fit and thread tolerance. Overall length is 2.5 inches with a thread length of 1 inch and a shank diameter of 0.255 inches. This is a single-piece unit sold individually.

This tap is used in manual tapping operations on a bench or in a tapping fixture. It is appropriate for threading blind holes in cast iron and non-ferrous metal workpieces where a bottoming chamfer is necessary to achieve full thread engagement close to the bottom of the hole. Series 5305 and 5303 designation covers standard hand tap configurations. Typical users include machinists, tool-and-die makers, maintenance technicians, and skilled trades personnel performing repair or fabrication work.

Key Features

• Bottoming chamfer allows threading to the base of blind holes
• High-speed steel construction provides durability across cast iron and non-ferrous metal applications
• Bright uncoated finish suitable for general-purpose tapping with standard cutting fluids
• H2 thread limit ensures consistent thread fit and tolerance control
• 4-flute straight-flute design for stable cutting in through and blind hole applications
• Right-hand thread direction, 1/4-20 UNC standard

Compatibility

Rated for use in cast iron and non-ferrous metal materials. Belongs to KENNAMETAL Series 5305 and 5303 hand tap product lines. Designed as a standard 1/4-20 UNC hand tap compatible with conventional tap wrenches and tapping fixtures accepting a 0.255-inch shank diameter.

Installation Notes

This tap is intended for use by machinists or qualified trades personnel performing manual threading operations. Always secure the workpiece and use the appropriate cutting fluid for the base material before beginning. Back the tap out periodically to clear chips and prevent binding, particularly in blind holes. Inspect the tap for wear or chipping before each use and replace if thread form shows degradation.