Osg 1400107901 Thread Forming Tap 5-40 Unc Cobalt

Product Description

The OSG 1400107901 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads in blind hole applications without cutting or removing material. Sized for 5-40 UNC threads, it is manufactured from cobalt high-speed steel and finished with a steam oxide coating to reduce friction and improve lubrication retention. The modified bottoming chamfer with 2 to 2.5 chamfered threads allows threading close to the bottom of blind holes. At 1.938 inches overall length with a 0.141-inch shank diameter, this tap fits standard tap wrenches and machine setups used by machinists and tool-and-die professionals.

This tap is suited for production and maintenance machining environments where thread integrity and hole-bottom proximity are critical. It carries a Class of Fit 2B with a Thread Limit of H5, making it appropriate for standard-tolerance UNC threaded assemblies. Specified material applications include alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel, covering a broad range of workpiece materials encountered in industrial and precision machining operations.

Key Features

• 5-40 UNC thread form with right-hand thread direction and 40 threads per inch
• Modified bottoming chamfer (2 to 2.5 chamfered threads) for threading close to blind hole bottoms
• Cobalt high-speed steel construction for performance in harder and abrasive workpiece materials
• Steam oxide coating reduces friction and aids in chip-free cold-forming operation
• Thread Limit H5 and Class of Fit 2B for consistent, standard-tolerance thread production
• No coolant-through design; suitable for use with externally applied cutting fluid or tapping compound

Compatibility

Designed for blind hole thread forming in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces requiring 5-40 UNC internal threads to a Class of Fit 2B standard.

Installation Notes

Thread forming taps should be installed by qualified machinists using a properly sized tap wrench or CNC tapping head aligned perpendicular to the workpiece surface. Ensure the spindle or driver is powered down before mounting or removing the tap. Apply an appropriate tapping compound or cutting fluid to the tap and workpiece before beginning the operation. Do not force the tap if resistance is encountered, as binding in hardened or stainless materials can cause tap breakage.