Osg 1400158108 Thread Forming Tap 4-40 Unc Cobalt Ticn

Product Description

The OSG 1400158108 is a thread forming tap designed for producing internal 4-40 UNC threads without cutting, using a cold-forming process that displaces material rather than removing chips. Built from cobalt high-speed steel and coated with titanium carbonitride (TiCN), this tap delivers extended tool life in demanding threading applications. The modified bottoming chamfer, with 2 to 2.5 chamfered threads, allows threading close to the bottom of a blind hole. With an overall length of 1.875 inches and a tapping depth of 0.559 inches, it fits standard hand tap drivers and machine tapping setups used by machinists and tool and die professionals.

This tap is suited for blind hole threading operations in a range of metallic workpiece materials including alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. The H9 thread limit designation makes it appropriate for standard tolerance thread production. It is commonly used in precision machining, toolroom work, and production environments where a strong, chipless thread form is required in ferrous and non-ferrous metals.

Key Features

• Thread forming (chipless) process eliminates chip evacuation concerns in blind holes
• Cobalt HSS construction provides heat resistance and durability in tough alloys
• TiCN coating reduces friction and extends tap life across a broad range of materials
• Modified bottoming chamfer (2 to 2.5 threads) allows threading close to hole bottom
• H9 thread limit for standard tolerance 4-40 UNC internal threads
• Right-hand thread direction for standard tapping operations

Compatibility

Designed for blind hole threading in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces requiring 4-40 UNC internal threads. Fits standard tap holders sized for a 0.141-inch shank diameter with a 0.110-inch square drive.

Installation Notes

Thread forming taps require proper tapping fluid or cutting oil suited to the workpiece material; dry tapping is not recommended. Ensure the workpiece is securely fixtured and the pilot hole diameter is sized correctly for the forming process, as forming taps require a slightly larger pilot hole than cutting taps for the same thread size. Power down or disengage the machine spindle before loading or removing the tap. Installation is typically performed by machinists or maintenance technicians using a tapping head, CNC machine, or hand tap wrench.