Osg 1730608 Spiral Point Tap 1/4-20 Unc Ticn Hss

Product Description

The OSG 1730608 is a spiral point tap designed to cut 1/4-20 UNC internal threads in through-hole applications. Built from Vanadium High Speed Steel (HSS-E) and coated with Titanium Carbonitride (TiCN), it delivers enhanced hardness and lubricity compared to standard uncoated HSS taps. The spiral point geometry pushes chips forward ahead of the cutting action, making it well suited for through-hole tapping where chip evacuation is critical. This tap carries a 3B class of fit designation with an H3 thread limit, producing threads within standard tolerance for general mechanical assembly. It is installed by machinists and tool-and-die professionals using a tap handle, CNC tapping head, or drill press tapping attachment.

The 1730608 is appropriate for tapping through holes in hardened steel, low-carbon steel, medium-carbon steel, and stainless steel. Its plug chamfer (3-5 thread lead) makes it a standard first-choice tap for production and maintenance tapping where the tap can pass fully through the workpiece. The TiCN coating reduces built-up edge and extends tool life when working in abrasive or work-hardening materials such as stainless steel. Right-hand thread direction matches standard 1/4-20 UNC fastener orientation.

Key Features

• Spiral point geometry pushes chips forward, optimized for through-hole tapping
• TiCN coating increases surface hardness and reduces friction for extended tool life
• Vanadium HSS-E base material provides toughness in steel and stainless steel applications
• H3 thread limit and 3B class of fit for standard-tolerance general assembly threads
• Plug chamfer with 3-flute design balances cutting load across the tap body
• No coolant-through requirement — compatible with flood coolant or cutting oil applied externally

Compatibility

Designed for cutting 1/4-20 UNC right-hand internal threads in hardened steel, low-carbon steel, medium-carbon steel, and stainless steel workpieces. Suitable for use in manual tap handles, tapping heads, and CNC machining centers equipped for rigid or floating tap cycles.

Installation Notes

This tap is installed by qualified machinists or tool-and-die technicians. Before tapping, verify the drilled hole is sized to the correct tap drill diameter for 1/4-20 UNC threads and that the workpiece is securely fixtured. Apply a suitable cutting fluid or tapping compound rated for the workpiece material — this is especially important when tapping stainless steel to prevent galling. Do not force the tap if resistance increases suddenly; back off to break chips and re-apply cutting fluid before continuing.