Osg 1145200 Straight Flute Tap 3/4-16 Unf Hss

Product Description

The OSG 1145200 is a straight flute plug tap designed for cutting internal 3/4-16 UNF right-hand threads in a wide range of ferrous and non-ferrous materials. Built from high-speed steel with a bright, uncoated finish, this tap delivers reliable thread form accuracy in production and maintenance applications. It carries a 2B class of fit and an H5 thread limit, making it suitable for standard commercial thread tolerances. The plug chamfer - typically 3 to 5 threads - allows the tap to start easily in through holes or holes with adequate clearance below the thread. Four flutes provide chip clearance and cutting edge support across the full thread engagement length.

This tap is suited for hand tapping and machine tapping operations in job shops, machine shops, and maintenance facilities. It performs in through-hole applications across a range of materials including low-carbon steel, medium-carbon steel, high-carbon steel, cast iron, aluminum, and cast aluminum. The straight flute geometry makes it most effective in shorter-chipping materials where chip evacuation by flute geometry is not critical. It is part of OSG Series 101, a catalog line of standard inch-size hand and machine taps.

Key Features

• 3/4-16 UNF right-hand thread form, 2B class of fit, H5 thread limit
• Plug chamfer for easy starting in through holes and sufficient-depth blind holes
• 4 flutes for chip clearance across the thread engagement zone
• High-speed steel construction for toughness in general-purpose tapping
• Bright, uncoated finish - no additional coating-related dimensional offset
• Straight flute design suited to short-chipping materials including cast iron and aluminum

Compatibility

Rated for tapping aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel. OSG Series 101 straight flute tap for standard 3/4-16 UNF internal thread applications.

Installation Notes

This tap should be installed and operated by a machinist or qualified maintenance technician familiar with tapping operations and thread standards. Always secure the workpiece and use a tapping fluid or cutting oil appropriate for the workpiece material before starting. For machine tapping, verify spindle speed, feed rate, and tap holder float are set correctly for the material and tap size before engaging. Power down and de-energize any machine tool before changing or inspecting the tap.