Kennametal 4131285 Hand Tap 1/2-13 Unc Bottoming Hss

Product Description

The KENNAMETAL 4131285 is a 1/2-13 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, this tap cuts right-hand threads to a 2B class of fit with an H5 thread limit. It carries a 4-flute straight-flute geometry, an overall length of 3.38 inches, and a thread length of 1.656 inches. The H5 limit provides controlled oversize tolerance, making it suitable for tapping blind holes to near-full thread depth. Licensed machinists, tool-and-die workers, and maintenance technicians are the primary installers.

This tap is used in hand-tapping operations where threads must extend close to the bottom of a blind hole. The bottoming chamfer — typically 1 to 2 threads of lead — allows the tap to cut nearly the full depth of a drilled hole after a plug or taper tap has started the thread. Typical applications include repair work, fixture fabrication, and production threading in cast iron and non-ferrous metal workpieces. It belongs to KENNAMETAL Series 5305 and 5303 and is sold individually.

Key Features

• Bottoming chamfer for threading close to the bottom of blind holes
• High-speed steel construction for durability across cast iron and non-ferrous metals
• Bright, uncoated finish — no coating buildup that could affect thread tolerance
• H5 thread limit provides consistent oversize control for 2B class-of-fit threads
• 4-flute straight-flute design for chip clearance in through and shallow blind holes
• Right-hand cut, 1/2-13 UNC — a common fastener thread in general mechanical work

Compatibility

Designed for use in cast iron and non-ferrous metal workpieces requiring 1/2-13 UNC right-hand internal threads to a 2B class of fit. Part of KENNAMETAL Series 5305 and 5303.

Installation Notes

Secure the workpiece firmly before tapping and use the appropriate tap wrench for controlled torque application. Apply a suitable cutting fluid for the workpiece material to reduce friction and extend tap life. Back the tap off periodically to break chips and prevent tap breakage, particularly in blind holes. Follow applicable shop safety practices and ensure the tap drill size matches the required minor diameter for 1/2-13 UNC before starting.