Osg 1719908 Spiral Flute Tap 5/16-18 Unc 3B Ticn

Product Description

The OSG 1719908 is a spiral flute tap designed for threading 5/16-18 UNC holes in difficult-to-machine materials. It features a modified bottoming chamfer, three right-hand flutes with a 10-degree helix angle, and a powdered metal construction with a TICN (Titanium Carbon Nitride) coating. The H3 thread limit and 3B class of fit make it suitable for standard commercial tolerance threading. The spiral flute geometry helps evacuate chips back out of the hole, reducing chip packing and improving thread finish. Licensed machinists, tool and die makers, and maintenance technicians use this tap in both production and repair applications.

This tap is engineered for use in stainless steel, hardened steel, titanium, and high-nickel alloys — materials that generate tough, stringy chips and demand a coating with high hardness and heat resistance. The TICN coating provides improved wear resistance over standard TiN, making it well suited for production runs in aerospace, medical, and industrial manufacturing environments. It is also applicable to one-off repair work where thread quality in tough alloys is critical.

Key Features

• 5/16-18 UNC thread form with H3 thread limit and 3B class of fit for standard commercial tolerances
• Modified bottoming chamfer allows threading close to the bottom of blind holes
• Spiral flute geometry evacuates chips upward, reducing packing in blind hole applications
• TICN coating provides high hardness and heat resistance for extended tool life in tough alloys
• Powdered metal substrate offers improved toughness and wear resistance over standard HSS
• Right-hand thread and right-hand flute direction; no coolant-through feature

Compatibility

Rated for use in stainless steel, hardened steel, titanium, and high-nickel alloys. Belongs to OSG Series 313NI, a line of spiral flute taps optimized for difficult-to-machine materials.

Installation Notes

Installation should be performed by a qualified machinist or maintenance technician using a calibrated tapping machine, CNC machine, or hand tap wrench appropriate for the workpiece setup. Always ensure the workpiece is securely fixtured and the tap is properly aligned before engaging the thread. Power down or de-energize any equipment before tapping in a live machine environment. Use a cutting fluid appropriate for the workpiece material, particularly when threading stainless steel or high-nickel alloys, to reduce heat buildup and extend tap life.