Balax 12648-01T Thread Forming Tap 1/4-20 Unc Bottoming

Product Description

The BALAX 12648-01T is a thread forming tap designed for cutting 1/4-20 UNC internal threads in blind hole applications. Unlike cut taps, thread forming taps displace material rather than remove chips, producing stronger threads with a burnished finish. This tap is manufactured from high-speed steel (HSS) with a titanium nitride (TiN) coating to extend tool life and reduce friction during tapping. It features a bottoming chamfer with 2.5 threads of lead, allowing threads to be formed close to the bottom of a blind hole. The H8 thread limit and 2B class of fit make it suitable for standard commercial threading tolerances. Machinists and tool and die professionals install this tap in CNC machining centers, drill presses, and manual tapping operations.

This tap is suited for blind hole threading in ductile and malleable materials where chip evacuation is a concern. The BXB series bottoming configuration allows thread forming to within a minimal distance of the hole bottom, making it a practical choice for close-tolerance work in production machining environments. The single oil groove aids lubrication delivery to the forming lobes during the tapping cycle, helping to maintain consistent thread quality across high-volume runs.

Key Features

• Thread forming design displaces material rather than cutting chips, reducing chip-related tap breakage in blind holes
• TiN coating extends tool life and lowers tapping torque compared to uncoated HSS
• Bottoming chamfer with 2.5P lead allows thread forming close to the bottom of blind holes
• H8 thread limit with 2B class of fit for standard commercial thread tolerance
• Right-hand thread direction, 1/4-20 UNC
• Single oil groove for lubrication during the tapping cycle

Compatibility

Designed for blind hole threading in ductile ferrous and non-ferrous materials that are suitable for thread forming rather than thread cutting. Verify material formability before use, as brittle or hard materials are not appropriate for cold-form tapping.

Installation Notes

Thread forming taps require a specific drill size larger than that used for cut tapping - consult a thread forming drill chart for the correct pilot hole diameter for 1/4-20 UNC before drilling. Use a quality tapping fluid appropriate for the work material and ensure it reaches the forming lobes throughout the cycle. Secure the workpiece and use a torque-controlled tapping head or CNC rigid tapping cycle where possible to avoid overloading the tap. Always follow shop safety procedures when operating drilling and tapping equipment.