Osg 1981901 Spiral Point Tap M12x1.75 Metric Coarse 3 Flute

Product Description

The OSG 1981901 is a spiral point tap designed for cutting M12x1.75 metric coarse internal threads in through-hole applications. Manufactured from high-speed steel with a steam oxide coating, it features a 3-flute plug chamfer configuration that pushes chips forward ahead of the cutting edge, keeping the flutes clear during the threading operation. The 6H class of fit meets standard tolerance requirements for metric fastener applications. With an overall length of approximately 85.7 millimeters and a thread length of 1-21/32 inches, this tap suits production and maintenance threading tasks. It is installed by machinists and maintenance technicians using a tap wrench, tapping head, or CNC machine tool.

The OSG 1981901 is suited for through-hole tapping in a wide range of materials including aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, high-carbon steel, and hardened steel. The plug chamfer distributes the cutting load across several leading threads, making it a practical choice for both manual and machine tapping in general industrial, maintenance, and fabrication environments. Right-hand thread direction aligns with standard fastener conventions for the majority of production applications.

Key Features

• M12x1.75 metric coarse thread form with 6H class of fit for standard tolerance requirements
• 3-flute spiral point geometry pushes chips forward for clean through-hole tapping
• High-speed steel construction provides toughness across a broad range of workpiece materials
• Steam oxide coating reduces friction and provides light corrosion resistance during storage and use
• Plug chamfer distributes cutting load over multiple lead threads for controlled thread entry
• Right-hand cut, D6 thread limit, no coolant-through requirement for simplified setups

Compatibility

Compatible with materials including aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, high-carbon steel, and hardened steel. Designed for use in standard M12x1.75 metric coarse through-hole tapping applications with a 6H thread tolerance class.

Installation Notes

This tap is installed by machinists or maintenance technicians using a tap wrench, floating tap holder, or rigid tapping head on a drill press, lathe, or CNC machining center. Ensure the pilot hole is drilled to the correct diameter for M12x1.75 before tapping. Apply appropriate cutting fluid for the workpiece material to extend tool life and improve thread quality. Secure the workpiece firmly before starting the tap to prevent misalignment and tap breakage.