Osg 1412902 Spiral Flute Tap 8-32 Unc Bottoming Hss

Product Description

The OSG 1412902 is a spiral flute bottoming tap designed for threading 8-32 UNC holes in a wide range of ferrous and non-ferrous materials. Built from high-speed steel and finished with an elektraLUBE coating, this tap is engineered for use in blind-hole applications where full thread depth close to the bottom of the bore is required. The right-hand, 3-flute spiral design with a 50-degree helix angle efficiently evacuates chips back through the flutes, reducing the risk of chip packing in confined holes. Overall length is 2-1/8 inches. Thread limit is H3, and the class of fit is 2B, making it suitable for standard unified thread applications across production and maintenance work.

This tap is suited for threading operations in residential and commercial maintenance, light manufacturing, and machine shop environments. The 8-32 UNC thread form is one of the most common fastener sizes in electrical enclosures, HVAC equipment panels, and mechanical assemblies. The bottoming chamfer style allows threads to be cut within one to two pitches of a blind hole bottom, making it the right choice when through-hole taps cannot reach full thread depth. Compatible materials include aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel.

Key Features

• Bottoming chamfer for maximum thread depth in blind holes
• 50-degree right-hand helix flute geometry for efficient chip evacuation
• elektraLUBE coating reduces friction and extends tool life in steel and aluminum
• High-speed steel construction provides durability across a broad material range
• H3 thread limit holds tight tolerances for consistent 2B class of fit
• 3-flute spiral design suited for through-feed and CNC tapping operations

Compatibility

Designed for threading 8-32 UNC blind holes in aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel. Part of OSG Series 107.

Installation Notes

This tap is installed by machinists, maintenance technicians, and trade professionals using a tap wrench, tapping head, or CNC tapping cycle. Always power down and lock out any machine before setting up tooling. Use an appropriate cutting fluid or tapping compound for the workpiece material, even when the elektraLUBE coating is present, to maximize tool life. Back the tap out periodically in hand-tapping operations to break and clear chips, particularly in deeper blind holes.