Osg 1400135001 Thread Forming Tap 3/8-16 Unc Cobalt

Product Description

The OSG 1400135001 is a thread forming tap designed for producing internal threads without cutting — material is displaced rather than removed, resulting in stronger threads and no chips. Built from cobalt high-speed steel with a steam oxide coating, this tap handles demanding applications in alloy steel, carbon steel, stainless steel, hardened steel, die steel, and aluminum. It carries a 3/8-16 UNC thread specification with a modified bottoming chamfer of 2 to 2.5 threads, allowing threading close to the bottom of blind holes. The H4 thread limit ensures dimensional accuracy across production runs. Part of the HY-PRO NRT series, this tap is a standard choice for machinists and toolroom technicians working in tight-tolerance environments.

This tap is built specifically for blind hole threading applications where chip evacuation is a concern and thread strength is critical. The thread forming action makes it well-suited for ductile materials including aluminum, low-carbon steel, and stainless steel. With a tapping depth of 1.252 inches and an overall length of 2.938 inches, it fits standard tap holders and CNC tapping heads used in production and job-shop machining environments. The right-hand thread direction and standard shank geometry make it compatible with common tapping equipment.

Key Features

• Thread forming design displaces material instead of cutting — eliminates chips in blind holes and produces stronger thread forms
• Cobalt high-speed steel construction provides heat and wear resistance in tough materials including hardened steel and stainless steel
• Steam oxide coating reduces friction and improves lubrication retention during tapping
• Modified bottoming chamfer (2 to 2.5 threads) allows threading close to the bottom of blind holes
• H4 thread limit maintains consistent thread tolerance across production volumes
• HY-PRO NRT series — engineered for use across a broad range of ferrous and non-ferrous materials

Compatibility

Designed for use in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces. Suitable for blind hole threading in production machining, toolroom, and maintenance applications requiring 3/8-16 UNC internal threads.

Installation Notes

Installation is performed by qualified machinists or toolroom technicians using a tap wrench, tapping head, or CNC machine with rigid or floating tap holder. Ensure the spindle speed and feed rate are appropriate for the workpiece material before tapping. Apply a suitable tapping fluid or cutting oil to the tap and hole prior to use, as thread forming generates significant friction and heat. Always secure the workpiece firmly and confirm the pilot hole diameter matches the recommended forming tap drill size for 3/8-16 UNC before beginning.