Osg 1101512305 Spiral Point Tap 3/8-16 Unc Tin Hss

Product Description

The OSG 1101512305 is a spiral point plug tap designed for right-hand threading in a wide range of metallic workpiece materials. Built from vanadium high speed steel (HSS) with a titanium nitride (TiN) coating, it delivers extended tool life and reduced friction at the cutting edge. The tap is ground to an H7 thread limit, producing 3/8-16 UNC threads with consistent dimensional tolerance. Its three-flute spiral point geometry pushes chips ahead of the tap and out of the hole, making it well-suited for through-hole tapping operations. Overall length is 2.938 inches with a thread length of 0.976 inches and a shank diameter of 0.381 inches.

This tap is used in machine shop, maintenance, and production environments where 3/8-16 UNC fastener threads are required. It is appropriate for use in drilling and tapping machines, CNC machining centers, and hand-held tapping arms. The plug chamfer style provides a moderate lead-in of several threads, making it a practical choice for starting in pre-drilled through holes. It is installed by machinists, tool and die technicians, and maintenance mechanics across industrial, commercial, and light manufacturing settings.

Key Features

• Spiral point geometry pushes chips forward through the hole, reducing chip packing in through-hole applications
• TiN coating increases surface hardness and reduces built-up edge, extending tool life across high-volume runs
• Vanadium HSS construction provides toughness and wear resistance in hard and abrasive materials
• H7 thread limit ensures consistent fit with standard 3/8-16 UNC mating fasteners
• Plug chamfer provides multi-thread lead-in for reliable starting in through holes
• Right-hand thread direction compatible with standard tapping equipment and spindles

Compatibility

Designed for through-hole tapping of 3/8-16 UNC threads. Compatible material applications include aluminum, hardened steel, stainless steel, high-carbon steel, low-carbon steel, medium-carbon steel, alloy steel, die steel, cast iron, high-nickel alloy, and titanium. Not rated for coolant-through use.

Installation Notes

This tap is installed by machinists and maintenance technicians using a tapping machine, CNC spindle, or manual tapping handle. Ensure the workpiece is securely fixtured and the pilot hole is drilled to the correct tap drill size for 3/8-16 UNC before starting. Apply cutting fluid appropriate to the workpiece material to reduce heat and extend tap life. Do not force the tap if resistance increases suddenly — back the tap out to clear chips before continuing.