Balax 12863-010 Thread Forming Tap 1/4-28 Unf Bottoming Hss

Product Description

The BALAX 12863-010 is a thread forming tap designed for producing internal threads in ductile materials without cutting. Sized for 1/4-28 UNF threads with a Class 2 fit and H3 thread limit, this bottoming-style tap reaches close to the bottom of blind holes. Manufactured from high-speed steel with a bright uncoated finish, it delivers consistent thread geometry and dimensional accuracy in production and maintenance applications. The right-hand spiral geometry displaces material rather than removing chips, reducing the risk of chip-related thread damage in blind hole work.

This tap is intended for blind hole threading operations where full thread depth close to the hole bottom is required. The bottoming chamfer, with 2.5 threads of lead, allows threads to be formed nearly to the bottom of a drilled hole. It is suited for use in light metals, mild steels, and other ductile materials in industrial maintenance, manufacturing, and general machining environments. Machinists and toolmakers are the primary installers.

Key Features

• 1/4-28 UNF thread size with Class 2 fit for standard tolerance threading
• Bottoming chamfer with 2.5P lead for threading close to blind hole bottoms
• H3 thread limit for consistent fit across production runs
• High-speed steel construction for durability in general machining applications
• Bright uncoated finish suitable for use with standard tapping oils and coolants
• Single oil groove design supports lubrication flow during forming

Compatibility

Designed as a thread forming tap for blind hole applications requiring 1/4-28 UNF right-hand internal threads with a Class 2 fit in ductile workpiece materials.

Installation Notes

Thread forming taps should be installed and driven by a qualified machinist using a properly sized tap wrench, tapping head, or CNC spindle set to the correct feed rate. Always apply an appropriate tapping fluid or cutting oil to the tap and workpiece before use. Ensure the drilled hole diameter matches the recommended forming tap drill size for 1/4-28 UNF to achieve the correct thread percentage. Do not use this tap on brittle materials such as cast iron, as thread forming requires material ductility.