YG-1 BB725 Spiral Flute Tap 3/4-16 Unf 4 Flute Hss

Product Description

The YG-1 BB725 is a spiral flute tap designed for cutting internal threads in ferrous and stainless steel workpieces. It cuts a 3/4-16 UNF thread to a 2B class of fit, meeting standard dimensional tolerances for unified fine-thread applications. The tap is manufactured from high speed steel with an oxide finish and features four right-hand flutes with a 40-degree helix angle. The modified bottoming chamfer allows threading close to the bottom of blind holes. An H5 thread limit ensures consistent sizing across production runs. Machinists and maintenance professionals install this tap by hand or with machine tapping equipment.

This tap is suited for threading operations on stainless steel and steel components in manufacturing, maintenance, and repair environments. The 40-degree fast-helix flute design helps evacuate chips efficiently, making it a practical choice for blind-hole threading where chip buildup is a concern. The right-hand flute and right-hand thread configuration is the standard orientation for general-purpose tapping on CNC machines, drill presses, or tapping arms.

Key Features

• 3/4-16 UNF thread form, 2B class of fit for standard tolerance applications
• 4-flute, 40-degree fast helix for efficient chip evacuation in blind holes
• Modified bottoming chamfer allows threading to near-bottom of blind bores
• H5 thread limit for controlled oversize sizing and consistent fit
• High speed steel construction with oxide finish for corrosion resistance during storage and use
• Right-hand flute and right-hand thread - compatible with standard tapping setups

Compatibility

Designed for threading stainless steel and steel workpieces requiring a 3/4-16 UNF internal thread. Coolant-through toolholders are not required, as this tap does not support coolant-through delivery.

Installation Notes

This tap should be installed by a machinist or tooling technician familiar with tapping feeds, speeds, and cutting fluids appropriate for the workpiece material. Always ensure the spindle is stopped and the machine is in a safe state before loading or removing taps from a toolholder. Use appropriate tapping fluid or cutting oil rated for stainless steel when threading stainless workpieces. Follow applicable shop safety procedures and machine-specific setup guidelines when setting depth stops for blind-hole applications.