Osg 2880601 Spiral Point Tap 1/4-20 Unc 2 Flute Plug 3B Hss

Product Description

The OSG 2880601 is a spiral point tap designed to cut 1/4-20 UNC threads in through-hole applications. It features a 2-flute, plug chamfer geometry that pushes chips forward ahead of the tap, reducing clogging and allowing smoother threading in production environments. Manufactured from high-speed steel and finished with a steam oxide coating, this tap provides corrosion resistance and mild lubricity during cutting. The right-hand thread direction and 3B class of fit make it a standard choice for general mechanical assemblies. Overall length is 2.5 inches with a thread length of 0.638 inches and a shank diameter of 0.255 inches. Licensed machinists, tool-and-die technicians, and maintenance professionals typically reach for this tap in manual and CNC tapping operations.

This tap is suited for through-hole tapping in aluminum, cast aluminum, low-carbon steel, and medium-carbon steel. The plug chamfer provides 3 to 5 chamfered threads, making it appropriate for materials where the tool can pass completely through the workpiece. It is commonly used in light manufacturing, maintenance and repair, and fabrication shops where 1/4-20 UNC threads are a frequent requirement. The spiral point design is particularly effective at higher tapping speeds where chip control is a priority.

Key Features

• Spiral point geometry pushes chips forward, reducing chip packing in through-hole applications
• Plug chamfer with 3 to 5 chamfered threads for standard through-hole entry
• High-speed steel construction provides toughness across a range of workpiece materials
• Steam oxide coating adds corrosion resistance and mild lubricity
• 3B class of fit for standard general-purpose thread tolerances
• Right-hand thread direction, no coolant-through requirement

Compatibility

Designed for tapping 1/4-20 UNC through-holes in aluminum, cast aluminum, low-carbon steel, and medium-carbon steel workpieces. Compatible with standard tap holders and CNC tapping chucks sized for a 0.255-inch shank diameter.

Installation Notes

Secure the workpiece and ensure the through-hole is drilled to the correct tap drill diameter before tapping. Use appropriate cutting fluid or tapping compound for the workpiece material to extend tap life and improve thread finish. Apply consistent, controlled feed pressure and confirm the tap is perpendicular to the work surface to avoid thread galling or tap breakage. Always follow shop safety protocols and use appropriate eye protection when operating tapping equipment.