Balax 12648-010 Thread Forming Tap 1/4-20 Unc Bottoming Hss

Product Description

The BALAX 12648-010 is a thread forming tap designed for cold-forming internal threads in ductile materials without cutting or chip production. Sized for 1/4-20 UNC threads with a 2B class of fit and H8 thread limit, this tap displaces material rather than removing it, producing stronger threads with better surface finish than cut taps. Built from high-speed steel with a bright uncoated finish, the 12648-010 features a bottoming chamfer of 2.5 threads, making it well-suited for threading close to the bottom of a blind hole. Overall length is 2.5 inches with a tapping depth of 1 inch. Licensed machinists, tool and die makers, and maintenance technicians install this type of tap across metalworking and industrial fabrication applications.

The 12648-010 is used for blind hole threading operations where a full thread form is required close to the bottom of the hole. The bottoming chamfer style requires that the hole be pre-tapped or that the operator use a plug or taper tap first to establish the thread before driving this tap to full depth. Its right-hand thread direction and 1/4-20 UNC sizing make it a standard choice in general manufacturing, HVAC equipment assembly, sheet metal fabrication, and light structural work where 1/4-20 fasteners are used. Part of the BALAX BXB series, this tap is intended for use in materials that flow rather than fracture under forming pressure.

Key Features

• Thread forming design eliminates chips, reducing tap breakage risk in blind hole applications
• Bottoming chamfer of 2.5 threads allows threading to within 2-3 pitches of hole bottom
• High-speed steel construction provides durability across a range of ductile workpiece materials
• H8 thread limit ensures proper fit tolerance for 2B class of fit 1/4-20 UNC threads
• Single oil groove supports lubrication flow during the forming operation
• Right-hand thread direction; compatible with standard tapping chucks and tap wrenches

Compatibility

Designed for blind hole thread forming operations producing 1/4-20 UNC internal threads with a 2B class of fit in ductile metals and similar materials that support cold forming.

Installation Notes

Thread forming taps require a lubricated tapping operation - always apply cutting or forming fluid appropriate to the workpiece material before use. Ensure the tap drill size matches the recommended forming tap drill chart for 1/4-20 UNC to achieve proper thread form and percentage. Because this is a bottoming chamfer tap, start the thread with a plug or taper tap if the hole is unprepared before driving the 12648-010 to depth. Use a calibrated torque-limiting tap wrench or tapping head to avoid tap breakage from overload.