Osg 1725308 Spiral Point Tap 7/8-14 Unf Ticn Hss

Product Description

The OSG 1725308 is a spiral point plug tap designed for cutting 7/8-14 UNF right-hand internal threads in a range of ferrous materials. Built from Vanadium High Speed Steel (HSS-E) and coated with Titanium Carbonitride (TiCN), this tap delivers extended tool life and reduced friction in demanding production or maintenance threading applications. The 3-flute spiral point geometry pushes chips forward ahead of the cutting zone, making it well-suited for through-hole tapping operations. At 4.689 inches overall length with a 1.37-inch thread length, it fits standard tap holders and drilling machine setups used by machinists and maintenance technicians.

The 1725308 is intended for threading through-holes in hardened steel, low-carbon steel, medium-carbon steel, and stainless steel workpieces. The plug chamfer distributes cutting load across several leading threads, making it a practical choice for production runs and repair work where a starting chamfer is not required. It conforms to a 3B class of fit and H4 thread limit, meeting standard tolerance requirements for UNF fastener applications in industrial, tooling, and mechanical assembly environments. This tap is appropriate for use in CNC machining centers, drill presses, and hand-tapping operations by qualified machinists and maintenance personnel.

Key Features

• 7/8-14 UNF thread form, right-hand cut, 3B class of fit with H4 thread limit
• Vanadium High Speed Steel (HSS-E) construction for improved wear resistance over standard M2 HSS
• TiCN coating reduces friction and heat buildup, extending tool life in ferrous materials
• 3-flute spiral point design pushes chips forward for efficient through-hole tapping
• Plug chamfer provides gradual thread engagement and distributes cutting forces
• No coolant-through requirement; compatible with flood, mist, or paste cutting lubricants

Compatibility

Rated for use in hardened steel, low-carbon steel, medium-carbon steel, and stainless steel. Designed for through-hole tapping applications requiring 7/8-14 UNF threads to a 3B class of fit. OSG Series 300.

Installation Notes

Installation and use should be performed by a qualified machinist or maintenance technician familiar with tapping speeds, feeds, and cutting fluid selection for the workpiece material. Secure the workpiece and verify spindle alignment before tapping to avoid tap breakage. Use appropriate cutting fluid for the material being tapped, particularly when working with stainless steel or hardened steel. Follow applicable shop safety procedures and machine guarding requirements throughout the operation.