Osg 2530001 Spiral Point Tap 1/4-20 Unc 3 Flute Hss

Product Description

The OSG 2530001 is a spiral point tap designed to cut 1/4-20 UNC right-hand threads in through-hole applications. Built from Vanadium High Speed Steel (HSS-E) with a steam oxide coating, it offers improved lubricity and resistance to chip welding during the threading process. The plug chamfer provides a gradual lead-in, distributing cutting forces across several threads. With 3 flutes and an H2 thread limit, this tap holds tight dimensional tolerances suited to a 2B class of fit. Overall length is 3.15 inches (80 mm) and thread length is 0.594 inches. It is installed by machinists, tool-and-die technicians, and maintenance professionals working with ferrous and non-ferrous materials.

The OSG 2530001 is suited for through-hole threading in a broad range of materials including aluminum, low-carbon steel, medium-carbon steel, high-carbon steel, alloy steel, die steel, stainless steel, and cast iron. The spiral point design pushes chips forward ahead of the tap rather than packing them behind it, making it the preferred choice for production threading on CNC machining centers, drill presses, and tapping machines where through-holes allow chip evacuation. It is typically used in general manufacturing, maintenance and repair operations, and fabrication shops.

Key Features

• 1/4-20 UNC thread form with right-hand cutting direction
• 3-flute spiral point geometry pushes chips forward for clean through-hole threading
• Plug chamfer (approximately 3-5 thread lead-in) for smooth entry and cutting force distribution
• Vanadium HSS-E construction for improved toughness and wear resistance over standard HSS
• Steam oxide coating reduces friction and improves chip flow
• H2 thread limit holds 2B class of fit tolerances

Compatibility

Designed for use in standard 1/4-20 UNC through-hole threading applications across a wide range of workpiece materials including aluminum, stainless steel, alloy steel, die steel, cast iron, and low-, medium-, and high-carbon steels. Not intended for blind-hole applications where chip evacuation forward is not possible.

Installation Notes

This tap is installed by machinists and maintenance technicians using a tapping machine, CNC machining center, or drill press with a tapping head. Ensure the workpiece is securely fixtured and the pilot hole is drilled to the correct tap drill diameter for 1/4-20 UNC before threading. Apply appropriate cutting fluid for the workpiece material to extend tap life and improve thread finish. Do not use in blind holes where forward chip evacuation is blocked, as this may cause tap breakage.