Osg 1700508 Spiral Point Tap 1/4-28 Unf 3 Flute Plug

Product Description

The OSG 1700508 is a spiral point tap designed for threading 1/4-28 UNF internal threads in demanding materials. Built from powdered metal and finished with a TiCN coating, this tap delivers extended tool life in applications where standard high-speed steel falls short. The plug chamfer style makes it a general-purpose choice for through-hole threading operations. With a 3-flute spiral point geometry, it pushes chips ahead of the cut rather than packing them into the flute, reducing the risk of tap breakage and improving thread finish. Suitable for use by machinists, tool-and-die makers, and maintenance professionals working in production or repair environments.

This tap is rated for use in hardened steel, stainless steel, high-nickel alloy, titanium, alloy steel, and die steel - material types common in aerospace, defense, industrial manufacturing, and precision machining. The right-hand thread direction and H6 thread limit classification indicate a slightly oversize cutting tolerance, which compensates for springback when tapping tougher alloys. The TiCN coating reduces friction and heat buildup at the cutting edge, extending tap life compared to uncoated alternatives. It is well-suited for job shops and maintenance operations that regularly encounter difficult-to-machine materials.

Key Features

• 1/4-28 UNF thread form, right-hand direction
• 3-flute spiral point geometry pushes chips forward for cleaner through-hole tapping
• Powdered metal construction provides higher wear resistance than standard HSS
• TiCN coating reduces friction and extends tool life in hard and abrasive materials
• H6 thread limit with oversize designation for use in springback-prone alloys
• Plug chamfer style for standard through-hole threading applications

Compatibility

Rated for hardened steel, stainless steel, high-nickel alloy, titanium, alloy steel, and die steel. OSG Series 312 designation. Designed as a replacement-style tap for 1/4-28 UNF through-hole applications in production and maintenance machining.

Installation Notes

Installation should be performed by a qualified machinist using a calibrated tapping head, CNC machine, or drill press with proper alignment. Always apply cutting fluid appropriate for the workpiece material, particularly when tapping stainless steel or high-nickel alloys. Ensure the tap is fully supported and running true before engaging the workpiece to avoid deflection or breakage. Follow shop safety protocols and applicable machine operation standards when changing or running cutting tools.