Emuge BU100501.5003 4-40 Unc Machine Tap Cobalt Nitride

Product Description

The EMUGE BU100501.5003 is a 4-40 UNC straight flute machine tap designed for threading operations in ferrous and non-ferrous metals where precision and tool life are critical. Built from cobalt high-speed steel with a nitride coating, this tap handles demanding materials including tool steel, austenitic iron, and low-alloyed casting steel. The modified bottoming chamfer allows threading closer to the bottom of blind holes than a standard bottoming tap. Overall length is 2.205 inches with a 0.433-inch thread length. It carries a right-hand thread direction, 2BX class of fit, and runs three straight flutes. Part of the EMUGE Rekord A-H series.

This tap is suited for both blind hole and through-hole threading applications in machine shop, manufacturing, and tool-and-die environments. It excels in tapping ferrous castings such as meehanite, perlitic, ferritic, and spheroidal graphite iron, as well as harder materials like high-speed steel and tool steel. The 4-40 thread size makes it a standard choice for small-fastener tapping in instrument, aerospace, and precision mechanical assemblies. Machine tool operators and machinists running CNC or manual tapping cycles will find the straight flute geometry appropriate for shorter chipping materials.

Key Features

• Cobalt HSS construction provides elevated heat and wear resistance compared to standard M2 HSS
• Nitride coating reduces friction and extends tool life in ferrous materials
• Modified bottoming chamfer enables threading near the bottom of blind holes
• 3-flute straight flute geometry suited for short-chipping and brittle materials
• 2BX class of fit for standard UNC thread tolerance in machine threading
• No coolant-through design - compatible with flood, mist, or paste lubricant delivery

Compatibility

Designed for 4-40 UNC threading in blind and through-hole applications across a range of materials including austenitic iron, bronze, ferritic iron, gunmetal, high-speed steel, low-alloyed casting steel, meehanite iron, perlitic iron, spheroidal graphite iron, and tool steel. Part of the EMUGE Rekord A-H series.

Installation Notes

This tap is intended for use in machine tapping operations on CNC machining centers, drill presses, or tapping heads - not recommended for hand tapping. Power down the machine spindle and secure the workpiece before tool changes. Apply an appropriate cutting fluid or tapping compound for the workpiece material to prevent galling and extend tap life. Follow shop-standard feeds and speeds for cobalt taps in the target material; do not exceed the tap's rated torque capacity for the 4-40 thread size.