Osg 1725105 Spiral Point Tap 9/16-18 Unf Tin Coated Hss

Product Description

The OSG 1725105 is a spiral point plug tap designed for cutting internal threads in through-hole applications. Built from Vanadium High Speed Steel (HSS-E) with a Titanium Nitride (TiN) coating, it delivers extended tool life and improved chip evacuation compared to uncoated taps. It carries a 9/16-18 UNF thread form, a 3B class of fit, and an H3 thread limit, making it suited for close-tolerance threaded connections in production and maintenance machining environments. With 3 flutes and a plug chamfer, it pushes chips forward through the hole during cutting. Machinists, tool and die workers, and maintenance technicians install this tap in drill presses, CNC machines, and hand tap applications.

This tap is applied in through-hole threading operations across a range of ferrous materials including low-carbon steel, medium-carbon steel, hardened steel, and stainless steel. It is part of the OSG Series 300 line and is suited for both production runs and field repair scenarios where a 9/16-18 UNF thread is required. The right-hand thread direction and plug chamfer make it appropriate for standard through-hole drilling sequences where the tap enters from one side and exits the other. Coolant-through capability is not available on this tap.

Key Features

• Vanadium High Speed Steel (HSS-E) construction for increased wear resistance over standard M2 HSS
• TiN coating reduces friction and extends tool life in ferrous materials
• Plug chamfer (3-5 thread lead) drives chips forward through the hole for clean through-hole threading
• H3 thread limit and 3B class of fit for consistent, close-tolerance thread production
• 3-flute design balances chip load and thread form quality in a range of steels
• Right-hand thread direction, compatible with standard tap holders and power drivers

Compatibility

Designed for through-hole tapping of 9/16-18 UNF threads in low-carbon steel, medium-carbon steel, hardened steel, and stainless steel. Compatible with standard tap holders, drill press chucks, and CNC tapping heads that accept a 0.429-inch shank diameter.

Installation Notes

This tap is installed by machinists and maintenance technicians using a drill press, tapping arm, CNC machining center, or hand tap wrench. Always ensure the pilot hole is drilled to the correct tap drill size for 9/16-18 UNF before tapping. Apply cutting fluid or tapping compound appropriate for the workpiece material, particularly when tapping stainless steel or hardened steel. Secure the workpiece firmly and align the tap perpendicular to the work surface before beginning the threading operation.