Osg 1226605 Spiral Point Tap 3/8-16 Unc Tin Hss

Product Description

The OSG 1226605 is a spiral point plug tap designed for cutting internal threads in through-hole applications. Built from high-speed steel (HSS) with a titanium nitride (TiN) coating, it delivers extended tool life and reduced friction during cutting. The 3/8-16 UNC thread profile and 3-flute spiral point geometry push chips forward ahead of the tap, keeping the flutes clear and reducing the risk of chip packing in the hole. With a thread limit of H2 and a right-hand thread direction, this tap is suited for general-purpose threading work across a broad range of ferrous and non-ferrous materials. It is installed by machinists, tool-and-die workers, and maintenance technicians.

This tap is rated for use in aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, high-carbon steel, and hardened steel. The plug chamfer — typically 3 to 5 threads of lead — makes it a practical choice for starting threads in through holes where full thread engagement is needed from the entry side. The TiN coating adds surface hardness and lubricity, which helps maintain cutting edge integrity across repeated use in production or maintenance environments. Coolant-through is not supported on this tap.

Key Features

• 3/8-16 UNC right-hand thread, H2 thread limit for controlled tolerance fit
• 3-flute spiral point geometry pushes chips forward in through-hole applications
• High-speed steel construction with TiN coating for extended tool life
• Plug chamfer for general-purpose through-hole threading
• Compatible with aluminum, cast iron, low- through high-carbon steel, and hardened steel
• No interrupted thread, no coolant-through — standard production tap configuration

Compatibility

Designed as a standard replacement or production tap for 3/8-16 UNC through-hole threading operations across aluminum, cast aluminum, cast iron, and low- to high-carbon and hardened steel workpieces.

Installation Notes

This tap is installed by machinists and maintenance technicians using a tap wrench, tapping head, or CNC rigid tapping cycle. Before use, ensure the pilot hole is drilled to the correct tap drill diameter for 3/8-16 UNC and that the workpiece is securely fixtured. Apply cutting fluid appropriate to the workpiece material to reduce heat and extend tap life. Do not force the tap if resistance is felt — back off to clear chips before continuing.