Osg 1680700 Straight Flute Tap 7/16-28 Unef Hss

Product Description

The OSG 1680700 is a straight flute plug tap designed for cutting 7/16-28 UNEF internal threads in a range of ferrous and non-ferrous metals. Built from high-speed steel with a bright uncoated finish, it produces clean, accurate threads in through-hole and open-ended applications. The plug chamfer provides a gradual thread lead-in, making it well suited for general-purpose tapping where the tap can pass through the material. With 4 flutes and an H3 thread limit, it maintains tight dimensional control for consistent thread fit across production and repair work. Licensed tradespeople and machining professionals install this tap using standard tapping equipment or CNC machining centers.

This tap is intended for threading operations in aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel. It is a practical choice for automotive, maintenance, and general manufacturing environments where UNEF thread forms are required. The straight flute design works best in shorter-chipping materials and through-hole conditions. The OSG 101N series construction meets the dimensional and performance expectations typical of production tapping in job shops and maintenance facilities.

Key Features

• 7/16-28 UNEF thread form for fine-pitch threading applications
• Plug chamfer for gradual thread engagement and lead-in
• 4 straight flutes optimized for shorter-chipping materials and through-hole tapping
• H3 thread limit for consistent, close-tolerance thread fit
• High-speed steel construction provides durability across a broad range of workpiece materials
• Bright uncoated finish suitable for use with standard cutting fluids

Compatibility

Rated for use in aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel workpieces. Part of the OSG 101N series.

Installation Notes

Installation should be performed by a qualified machinist or maintenance technician using a properly sized tap wrench, tapping head, or CNC rigid tapping spindle. Always apply an appropriate cutting fluid for the workpiece material to extend tool life and improve thread quality. Secure the workpiece before tapping and ensure the tap is aligned perpendicular to the drilled hole. Do not force a damaged or dull tap, as this can result in tap breakage and workpiece damage.