Osg 1736801 Spiral Point Tap 1/4-28 Unf 3 Flutes Plug

Product Description

The OSG 1736801 is a spiral point plug tap designed for cutting right-hand internal threads to a 1/4-28 UNF specification. Built from vanadium high-speed steel (HSS-E) with a steam oxide coating, it delivers controlled chip ejection ahead of the cutting edge, making it well-suited for through-hole tapping applications. The 2B class of fit and H4 thread limit ensure threads meet standard fastener tolerances. With 3 flutes and a plug chamfer, this tap provides a balance of strength and lead-in guidance appropriate for production and maintenance tapping operations.

This tap is intended for use in through-hole applications across a range of ferrous materials including low-carbon steel, medium-carbon steel, hardened steel, and stainless steel. The steam oxide finish reduces friction and provides a degree of chip flow improvement in these materials. It is a standard choice for machinists, maintenance technicians, and tool-and-die professionals working on threaded fastener repairs or new thread creation in metal components. The Series 300 designation identifies it within OSG standard tooling lines.

Key Features

• 1/4-28 UNF right-hand thread form with 2B class of fit and H4 thread limit
• Spiral point geometry ejects chips forward, ideal for through-hole tapping
• Vanadium high-speed steel (HSS-E) construction for improved wear resistance over standard HSS
• Steam oxide coating reduces friction and improves performance in ferrous materials
• Plug chamfer provides gradual thread engagement for reliable starts
• No coolant-through design; compatible with standard cutting fluid application

Compatibility

Rated for use in hardened steel, low-carbon steel, medium-carbon steel, and stainless steel. Designed as an OEM-style replacement or standard tooling selection for 1/4-28 UNF through-hole tapping operations.

Installation Notes

Installation should be performed by a qualified machinist or maintenance technician using a tapping machine, drill press, or CNC with appropriate feed and speed settings for the workpiece material. Always apply cutting fluid or tapping compound appropriate for the material being threaded. Ensure the starting hole diameter meets the recommended tap drill size for 1/4-28 UNF before engaging the tap. Inspect the tap for wear or chipping before each use to avoid thread quality issues.