Osg 2842201 Spiral Point Tap 7/16-20 Unf 3 Flute

Product Description

The OSG 2842201 is a spiral point plug tap ground from vanadium high speed steel (HSS-E) and finished with a steam oxide coating. It cuts a 7/16-20 UNF right-hand internal thread and is designed for through-hole tapping applications. The spiral point geometry pushes chips forward ahead of the cutting action, reducing chip clogging in production and maintenance machining environments. With 3 flutes, an H5 thread limit, and a plug chamfer, this tap is suited for machinists, tool-and-die technicians, and maintenance professionals working in metal fabrication or repair.

The 2842201 is rated for use across a broad range of ferrous and non-ferrous metals including aluminum, low-carbon steel, medium-carbon steel, high-carbon steel, alloy steel, die steel, cast iron, hardened steel, and stainless steel. It is well suited to general-purpose threading in through-hole applications on CNC machining centers, drill presses, and tapping fixtures where chip evacuation forward through the hole is practical. The plug chamfer provides a gradual lead-in over the first few threads, making it appropriate for most standard through-hole threading setups.

Key Features

• 7/16-20 UNF right-hand thread form for standard inch fine-thread applications
• Vanadium high speed steel (HSS-E) construction for improved wear resistance over standard HSS
• Steam oxide coating reduces friction and provides light corrosion resistance during storage and use
• Spiral point design pushes chips ahead into through-holes, minimizing chip packing
• H5 thread limit provides controlled oversize tolerance for plated or close-tolerance fits
• No coolant-through requirement — compatible with flood coolant or cutting oil applied externally

Compatibility

Designed for through-hole tapping of 7/16-20 UNF threads in aluminum, hardened steel, stainless steel, high-carbon steel, low-carbon steel, medium-carbon steel, alloy steel, die steel, and cast iron. Part of OSG Series 280.

Installation Notes

This tap is installed by machinists and maintenance technicians using a tap wrench, tapping head, or CNC rigid tapping cycle. Power down or de-energize any machine before manually installing or removing the tap from a holder. Use an appropriate cutting fluid or tapping compound for the workpiece material to extend tool life and improve thread finish. Do not reverse the tap without breaking the chip first in manual operations, and never force the tap past its cutting capacity in hard materials.