Osg 1654502508 Spiral Flute Tap 1-1/4-7 Unc 4 Flute

Product Description

The OSG 1654502508 is a spiral flute tap designed for cutting 1-1/4-7 UNC internal threads in a wide range of ferrous and non-ferrous materials. Built from powdered metal with a V coating, this tap delivers consistent performance across alloy steel, stainless steel, cast iron, aluminum, and multiple carbon steel grades. It features a 45-degree right-hand helix and a modified bottoming chamfer, making it suitable for threading holes where depth control is critical. Coolant-through capability supports chip evacuation and tool life in production environments. The tap meets a 2B class of fit, the standard tolerance for general-purpose UNC threaded assemblies.

This tap is suited for CNC machining centers, drill presses, and tapping machines in industrial manufacturing, maintenance, and toolroom applications. The spiral flute geometry evacuates chips upward out of the hole, making it particularly effective in blind-hole situations. Its material compatibility list spans Alloy Steel, Aluminum, Cast Aluminum, Cast Iron, Hardened Steel, High-Carbon Steel, Low-Carbon Steel, Medium-Carbon Steel, and Stainless Steel, covering most production and repair threading scenarios encountered in metalworking shops.

Key Features

• 1-1/4-7 UNC thread form, right-hand thread direction, 2B class of fit
• 45-degree right-hand spiral flute for efficient upward chip evacuation in blind holes
• Modified bottoming chamfer for threading close to the bottom of blind holes
• Powdered metal construction with V coating for extended tool life across diverse workpiece materials
• Coolant-through design supports high-production tapping with consistent chip control
• H1 thread limit for tight tolerance control on finished thread size

Compatibility

Designed as an OEM-style replacement or direct-use spiral flute tap for 1-1/4-7 UNC threading applications across the material types listed in OSG Series 16545.

Installation Notes

Installation and use of this tap should be performed by a qualified machinist familiar with tapping speeds, feeds, and cutting fluid selection for the workpiece material. Ensure the machine spindle and tap holder are properly aligned before engagement to avoid tap breakage or thread damage. Use appropriate cutting fluid or coolant for the workpiece material, particularly when threading stainless or hardened steels. Never reverse a broken tap without proper extraction tooling.