Osg 1652501708 Spiral Flute Tap 1/4-20 Unc 2 Flute

Product Description

The OSG 1652501708 is a spiral flute tap designed for threading 1/4-20 UNC holes in a wide range of ferrous and non-ferrous metals. It features a 45-degree right-hand helix that pulls chips up and out of the hole during tapping, making it well suited for through-hole and semi-bottoming blind-hole applications. Manufactured from powdered metal and finished with a TICN coating, the tap delivers improved wear resistance and surface hardness compared to standard high-speed steel. Thread limit is H5 with a 2B class of fit, producing threads that meet standard tolerance requirements for most fastener assemblies. Overall length is 5.96 inches with a 0.398-inch thread length.

This tap is intended for use in machine shop, manufacturing, and maintenance environments where consistent thread quality is required across production runs or repair work. It is appropriate for use on alloy steel, aluminum, cast aluminum, cast iron, hardened steel, high-carbon steel, low-carbon steel, medium-carbon steel, and stainless steel. The semi-bottoming chamfer allows threading close to the bottom of a blind hole while still providing enough lead-in to start the tap cleanly. Machinists and tooling technicians working with CNC machining centers, drill presses, or tapping arms will find this tap suitable for their standard 1/4-20 threading operations.

Key Features

• 45-degree spiral flute helix evacuates chips efficiently during blind and through-hole tapping
• Powdered metal construction provides higher wear resistance than conventional HSS
• TICN coating reduces friction and extends tool life across abrasive materials
• H5 thread limit and 2B class of fit for standard tolerance thread production
• Semi-bottoming chamfer allows tapping close to the bottom of blind holes
• Right-hand flute direction and right-hand thread for standard CW rotation

Compatibility

Designed for threading 1/4-20 UNC holes in alloy steel, aluminum, cast aluminum, cast iron, hardened steel, high-carbon steel, low-carbon steel, medium-carbon steel, and stainless steel. Part of OSG Series 16525.

Installation Notes

Install in a tap holder, tapping head, or CNC rigid tapping spindle sized for the 0.255-inch shank diameter before use. Ensure the workpiece is securely fixtured and the spindle is properly aligned to the hole axis to prevent tap breakage. Use an appropriate cutting fluid or tapping compound for the workpiece material, particularly when tapping stainless or hardened steel. Never reverse the tap under load without confirming the machine or holder is set for proper back-out to avoid thread damage or breakage.