Osg 1731105 Spiral Point Tap 3/8-24 Unf Tin Hss

Product Description

The OSG 1731105 is a spiral point tap designed for cutting internal threads in through-hole applications. It produces a 3/8-24 UNF right-hand thread and uses a plug chamfer to guide entry and distribute cutting load across the leading threads. The tap is manufactured from vanadium high-speed steel (HSS-E) for improved toughness and wear resistance at elevated cutting temperatures. A titanium nitride (TiN) coating reduces friction and extends tool life across repeated use cycles. With 3 flutes and an H3 thread limit, it is suited for consistent, close-tolerance production threading. Licensed machinists and tool-and-die professionals are the primary users of this tap.

This tap is built for threading through-holes in hardened steel, low-carbon steel, medium-carbon steel, and stainless steel. The spiral point design pushes chips forward ahead of the tap, making it the correct choice for through-hole work rather than blind-hole applications. It fits standard tap handles and CNC tapping heads. The 3B class of fit specifies a standard tolerance range appropriate for general-purpose fastener assemblies. Series 300 designation indicates OSG standard production tooling.

Key Features

• 3/8-24 UNF thread form, right-hand cut, H3 thread limit for close tolerance control
• Plug chamfer provides guided entry and distributes cutting forces over multiple lead threads
• Vanadium high-speed steel (HSS-E) construction for improved heat and wear resistance
• TiN coating reduces cutting friction and extends tap service life
• Spiral point geometry pushes chips forward, optimized for through-hole threading
• 3B class of fit meets standard assembly tolerance requirements

Compatibility

Designed for use in hardened steel, low-carbon steel, medium-carbon steel, and stainless steel workpieces requiring a 3/8-24 UNF through-hole thread. Compatible with standard tap handles, tapping attachments, and CNC rigid tapping setups accepting a 0.381-inch shank diameter.

Installation Notes

This tap is installed by machinists and tool-and-die technicians using manual tap handles or machine tapping setups. The workpiece must be securely fixtured and the pilot hole drilled to the correct tap drill diameter for a 3/8-24 UNF thread before tapping begins. Apply cutting fluid appropriate for the workpiece material to reduce heat buildup and extend tap life. Do not force the tap if resistance is encountered; back off to clear chips and re-engage to avoid breakage.