Osg 2631805 Spiral Point Tap 3/8-24 Unf Tin Hss

Product Description

The OSG 2631805 is a spiral point tap designed for machine tapping of through-hole threads in a wide range of ferrous and non-ferrous metals. It cuts a 3/8-24 UNF right-hand thread to a 2B class of fit using a 3-flute, plug chamfer geometry that pushes chips forward ahead of the cutting action, keeping flutes clear during the cut. The tap is manufactured from vanadium high-speed steel (HSS-E) and finished with a titanium nitride (TiN) coating to extend tool life and reduce friction at the cutting edge. Overall length is 3.937 inches (100 mm) with a thread length of 0.752 inches. Coolant-through capability is built in, supporting high-production machining environments.

This tap is suited for through-hole tapping operations on CNC machining centers, drill presses, and tapping machines in production and job-shop settings. The TiN coating and HSS-E substrate make it appropriate for aluminum, cast iron, low-, medium-, and high-carbon steel, alloy steel, die steel, and stainless steel. The spiral point geometry is most effective in through-holes where chips can be evacuated forward without packing. It is part of OSG Series 260 and is sold individually.

Key Features

• 3/8-24 UNF thread form, right-hand cut, 2B class of fit for standard UNF through-hole applications
• Spiral point (gun tap) geometry pushes chips forward, reducing chip packing in through-holes
• Vanadium high-speed steel (HSS-E) construction for improved wear resistance over standard M2 HSS
• TiN coating reduces friction and heat buildup, extending tool life across a broad range of workpiece materials
• Coolant-through design supports high-speed, high-production machine tapping
• Plug chamfer (3-5 thread lead) for general-purpose through-hole starting without bottoming requirements

Compatibility

Designed for machine tapping of 3/8-24 UNF through-holes in aluminum, hardened steel, stainless steel, high-carbon steel, low-carbon steel, medium-carbon steel, alloy steel, die steel, and cast iron. Not intended for blind-hole applications where chip evacuation forward is restricted.

Installation Notes

This tap should be installed by a machinist or tooling technician in a rigid tapping chuck or floating tap holder appropriate for the machine tool in use. Ensure the spindle speed and feed rate are set to the tap manufacturer's recommendation for the workpiece material before starting the cycle. Coolant supply should be confirmed active before running if the coolant-through feature is used. Inspect the tap for chipping or wear before each production run and replace at first sign of tool degradation to avoid thread damage in the workpiece.