Kennametal 1542493 Hand Tap 5/16-18 Unc Bottoming Hss

Product Description

The KENNAMETAL 1542493 is a 5/16-18 UNC straight flute hand tap designed for bottoming applications in production and maintenance threading work. Built from high-speed steel (HSS) with a bright, uncoated finish, it cuts right-hand internal threads to a Class 3B fit with an H3 thread limit, delivering tight dimensional control for precision assemblies. The 2-flute straight flute geometry channels chips out efficiently in through-hole applications. With an overall length of 2.72 inches and a thread length of 1.125 inches, this tap is sized for standard bench and machine use. It is part of Kennametal Series 5305 and 5303.

This tap is suited for threading cast iron and non-ferrous metals in both shop and field settings. The bottoming chamfer style allows threading close to the bottom of a blind hole, making it the appropriate choice when thread engagement must extend to near the full depth of a drilled hole. It is commonly used as the final tap in a tapping sequence following a taper or plug tap, or as the sole tap in through-hole operations where full thread depth near the bottom is required. Machinists, tool-and-die workers, and maintenance technicians are the primary users.

Key Features

• 5/16-18 UNC thread form, right-hand direction, Class 3B fit
• H3 thread limit for controlled oversize tolerance
• Bottoming chamfer for threading to near the bottom of blind holes
• 2-flute straight flute geometry suited to cast iron and non-ferrous materials
• Bright, uncoated high-speed steel construction - no coating to affect thread dimensions
• Overall length 2.72 inches, thread length 1.125 inches, shank diameter 0.318 inches

Compatibility

Designed for use in standard tap handles and tapping heads accepting a 0.318-inch shank diameter. Compatible material applications include cast iron and non-ferrous metals per Kennametal Series 5305 and 5303 specifications.

Installation Notes

This tap is installed by hand or with a tap wrench and should be used with appropriate cutting fluid for the workpiece material. Always ensure the drilled hole matches the recommended tap drill diameter for 5/16-18 UNC threads before tapping. Secure the workpiece and apply steady, even pressure while reversing periodically to break chips. Follow applicable shop safety practices and OSHA general machine tool guidelines when operating in a production environment.