Osg 2885005 Spiral Point Tap 4-40 Unc Tin Hss

Product Description

The OSG 2885005 is a spiral point tap designed for cutting 4-40 UNC internal threads in through-hole applications. Built from high-speed steel with a titanium nitride (TiN) coating, this plug-chamfer tap is engineered for production tapping in soft to medium-hardness metals. The 2-flute spiral point geometry pushes chips forward ahead of the cutting edge, keeping the flutes clear and reducing the risk of chip packing in through-hole work. With a class 2B thread fit and H3 thread limit, the tap produces threads within standard tolerance for general mechanical assembly. Overall length is 1.875 inches with a thread length of 0.319 inches and a shank diameter of 0.141 inches.

This tap is suited for production and maintenance threading operations in aluminum, cast aluminum, low-carbon steel, and medium-carbon steel. The plug chamfer — typically 3 to 5 threads — allows the tap to be started easily in a drilled hole and is the most common chamfer style for general-purpose through-hole tapping. It is well-suited for use in CNC tapping, drill press, and hand-tapping setups where right-hand threads and consistent thread quality are required. The TiN coating extends tool life by reducing friction and heat buildup at the cutting edge.

Key Features

• Spiral point geometry pushes chips forward, ideal for through-hole tapping
• TiN coating reduces friction and extends tool life in production environments
• High-speed steel construction handles aluminum, cast aluminum, low-carbon steel, and medium-carbon steel
• Plug chamfer for easy hole entry and general-purpose use
• Class 2B fit with H3 thread limit for standard tolerance internal threads
• Right-hand thread direction, no coolant-through, non-interrupted thread form

Compatibility

Designed for tapping 4-40 UNC through-holes in aluminum, cast aluminum, low-carbon steel, and medium-carbon steel workpieces. Suitable for CNC tapping centers, drill presses, and hand-tapping applications requiring a standard 2B class of fit.

Installation Notes

Install this tap using a tap wrench, tapping head, or CNC rigid tapping cycle appropriate to the machine setup. Ensure the correct tap drill size for 4-40 UNC is used prior to tapping to achieve the specified thread class. Apply cutting fluid or tapping compound appropriate to the workpiece material to preserve coating life and thread quality. Secure the workpiece fully before starting the tap to prevent thread misalignment.