Osg 1400126208 Thread Forming Tap 1/4-20 Unc Cobalt Ticn

Product Description

The OSG 1400126208 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without cutting chips. Built from cobalt high-speed steel and coated with titanium carbonitride (TiCN), it handles tough materials where standard HSS taps wear prematurely. The 1/4-20 UNC thread form and modified bottoming chamfer allow threading close to the bottom of blind holes. At 2.5 inches overall length with a 0.594-inch thread length and H4 thread limit, this tap suits precision applications where dimensional consistency across batches is critical. Licensed HVAC, plumbing, and mechanical trades use thread forming taps when working with ductile metals where chip evacuation in blind holes is a concern.

This tap is suited for blind hole threading in residential and commercial maintenance, fabrication, and repair settings. It performs in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. The modified bottoming chamfer with 2 to 2.5 chamfered threads provides good thread engagement close to the blind hole floor, making it a practical choice when thread depth is constrained by component design. It is used by machinists, maintenance mechanics, and field technicians working with threaded fastener repairs or custom component fabrication.

Key Features

• Thread forming (chipless) design eliminates chip evacuation issues in blind holes
• Cobalt HSS construction provides elevated heat and wear resistance over standard M2 HSS
• TiCN coating reduces friction and extends service life in abrasive and hard materials
• Modified bottoming chamfer (2 to 2.5P) enables threading near the bottom of blind holes
• H4 thread limit ensures consistent fit and gauge compliance across production runs
• Right-hand thread direction, compatible with standard tapping equipment and hand tools

Compatibility

Designed for use in blind hole threading applications across alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces requiring a 1/4-20 UNC internal thread.

Installation Notes

Thread forming taps require adequate lubrication or cutting fluid matched to the workpiece material — use appropriate tapping fluid for steel or aluminum before starting. Secure the workpiece fully before tapping and use a calibrated torque handle or tapping head to avoid overload and breakage. Ensure the tap is aligned perpendicular to the workpiece surface to maintain thread straightness. Inspect the H4 thread limit with a go/no-go gauge after tapping to confirm dimensional compliance.