Osg 1012108 Straight Flute Tap 4-40 Unc Ticn Hss

Product Description

The OSG 1012108 is a straight flute tap designed for cutting 4-40 UNC internal threads in a wide range of metals. It features three flutes, a taper chamfer for easier thread starting, and is manufactured from high-speed steel with a TiCN coating for improved wear resistance and tool life. With an overall length of 1-7/8 inches and a thread length of 9/16 inches, this tap suits production and maintenance threading operations. The right-hand thread direction and H2 thread limit make it a practical choice for machinists and maintenance techs working to standard tolerances in light-duty threaded assemblies.

This tap is intended for threading operations in aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel. It fits standard CNC machining centers, drill presses, and tapping machines used in production shops, maintenance facilities, and toolrooms. The 4-40 UNC size is common in small fastener applications including instrument enclosures, electronics hardware, and precision mechanical assemblies. Class of fit 2B and 3B coverage makes it versatile for both general-purpose and closer-tolerance threaded holes.

Key Features

• Taper chamfer for guided thread engagement and easier starting in blind or through holes
• TiCN coating increases surface hardness and reduces friction for extended tool life in ferrous and non-ferrous materials
• H2 thread limit provides controlled oversize for consistent 2B and 3B class-of-fit results
• Three-flute design balances chip clearance and cutting edge strength in small-diameter tapping
• Right-hand thread direction compatible with standard tapping heads and CNC rigid tapping cycles
• No coolant-through requirement simplifies use on conventional tapping equipment

Compatibility

Designed for use in applications requiring 4-40 UNC threads with a 2B or 3B class of fit. Compatible with aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, and high-carbon steel workpiece materials as specified by the manufacturer.

Installation Notes

This tap should be installed by a machinist or maintenance technician familiar with tapping operations and proper speeds and feeds for the workpiece material. Ensure the workpiece is securely fixtured and the tap is properly aligned before engagement to avoid tap breakage at this small diameter. Use an appropriate tapping fluid or cutting oil for the material being threaded. Follow shop safety practices and machine-specific lockout procedures before changing tooling.