Osg 1733201 Spiral Flute Tap 7/16-14 Unc Vanadium Hss

Product Description

The OSG 1733201 is a spiral flute tap designed for cutting 7/16-14 UNC internal threads in ferrous materials. It features a 45-degree helix angle that evacuates chips upward out of the hole, making it well suited for blind-hole applications where chip packing is a concern. The tap is ground from vanadium high-speed steel and finished with a steam oxide coating to reduce friction and improve lubricity during the cut. With a modified bottoming chamfer, it threads closer to the bottom of a blind bore than a plug or taper tap. Overall length is 3.156 inches. Thread limit is H3, appropriate for general-tolerance UNC threading work.

This tap is rated for use in stainless steel, high-carbon steel, low-carbon steel, and medium-carbon steel. It is a single-tap solution for shops and field machinists cutting 7/16-14 UNC threads in blind holes where a standard plug tap cannot reach the required thread depth. The Series 303 designation places it within OSG's production-grade catalog line for spiral flute taps. Typical applications include manufacturing, maintenance and repair, and fabrication environments where precise thread form and chip control are both required.

Key Features

• 45-degree right-hand helix angle for upward chip evacuation in blind holes
• Modified bottoming chamfer threads closer to the bottom of a blind bore
• Vanadium high-speed steel construction for wear resistance in ferrous materials
• Steam oxide coating reduces friction and built-up edge during threading
• H3 thread limit for standard general-tolerance UNC thread fit
• Right-hand thread direction, no coolant-through requirement

Compatibility

Rated for threading stainless steel, high-carbon steel, low-carbon steel, and medium-carbon steel. Designed for 7/16-14 UNC blind-hole applications requiring a modified bottoming chamfer profile.

Installation Notes

Installation is performed by machinists or maintenance technicians using a tap wrench, drill press, or CNC tapping cycle. Ensure the pilot hole diameter matches the recommended tap drill size for 7/16-14 UNC threads before starting. Apply appropriate cutting fluid or tapping compound for the workpiece material, particularly when threading stainless steel. Back the tap out periodically to break and clear chips when working in deep blind holes.