Osg 2809601 Spiral Point Tap 1/4-28 Unf Plug Hss

Product Description

The OSG 2809601 is a spiral point tap designed for cutting internal threads in through-hole applications. Built from 3% vanadium high-speed steel (HSS-E) with a steam oxide coating, it produces clean 1/4-28 UNF threads in a wide range of workpiece materials. The spiral point geometry pushes chips forward ahead of the cutting zone, keeping flutes clear and reducing tap breakage in production threading operations. With a plug chamfer, 3 flutes, and an H2 thread limit, this tap suits general-purpose machine tapping where consistent thread quality and tool life are the priority. Machinists and tool-and-die technicians reach for this series in both manual and CNC tapping setups.

This tap is suited for threading through holes in aluminum, low-carbon steel, medium-carbon steel, high-carbon steel, alloy steel, die steel, stainless steel, hardened steel, and cast iron. The oxide finish reduces friction and provides light lubrication retention, making it a practical choice for production runs and job-shop work where a broad material capability is needed from a single tap. Right-hand thread direction matches standard fastener orientation in the vast majority of industrial and mechanical assembly applications.

Key Features

• Spiral point design pushes chips forward, ideal for through-hole tapping
• 3% vanadium HSS-E construction provides increased wear resistance over standard M2 HSS
• Steam oxide coating reduces friction and extends tool life across varied materials
• Plug chamfer (3-5 thread lead) balances cutting load for general machine tapping
• H2 thread limit suits standard tolerance class 2B UNF thread requirements
• Right-hand cut, no coolant-through requirement - compatible with flood or brush lubrication

Compatibility

Designed for use in standard tap holders and quick-change tapping chucks accepting a 0.255-inch shank diameter. Cuts 1/4-28 UNF right-hand threads in through-hole configurations across aluminum, carbon steels, alloy steels, stainless steel, die steel, and cast iron workpieces.

Installation Notes

Secure the workpiece firmly before tapping and ensure the hole is drilled to the correct tap drill diameter for 1/4-28 UNF threads per applicable engineering standards. Apply cutting fluid appropriate to the workpiece material - sulfurized oil for steels, water-soluble coolant or kerosene for aluminum - to maximize thread quality and tap life. Do not exceed the tap's rated cutting speed for the material being threaded; consult the OSG Series 280 speed and feed guidelines. Inspect tap condition regularly in production runs and replace at first sign of chipping or thread form degradation.