Osg 1971200 Straight Flute Tap M8x1.25 Metric Coarse 4 Flute

Product Description

The OSG 1971200 is a straight flute tap designed for cutting M8x1.25 metric coarse internal threads in a wide range of ferrous and non-ferrous materials. Built from high-speed steel with a bright uncoated finish, this taper chamfer tap is suited for through-hole and blind-hole applications where chip evacuation is managed manually or with cutting fluid. The 6H class of fit and D5 thread limit deliver consistent, on-tolerance threads for standard metric fastener assemblies. Overall length is 2-23/32 inches with a 1-1/8 inch thread length, making it compatible with standard tap holders and hand-tapping setups.

This tap is used in machine shop, maintenance, and production environments wherever M8x1.25 metric coarse threads are required. The taper chamfer distributes cutting load across the leading threads, making it easier to start the tap squarely in the hole. Material applications include aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel. It is installed by hand or with a tapping attachment on a drill press or CNC machining center.

Key Features

• M8x1.25 metric coarse thread form, 6H class of fit for standard tolerance applications
• Taper chamfer distributes cutting load for easier tap starting and reduced breakage risk
• 4 straight flutes suitable for through-hole tapping and short-chipping materials
• High-speed steel construction provides good wear resistance across a broad material range
• Bright uncoated finish for use with a wide variety of cutting fluids
• D5 thread limit for consistent thread quality across production runs

Compatibility

Designed as an OEM-style replacement or direct-use tap for M8x1.25 metric coarse thread applications across aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel workpieces. Part of OSG Series 141.

Installation Notes

Machinists and maintenance technicians should secure the workpiece firmly before tapping and ensure the pilot hole is drilled to the correct minor diameter for M8x1.25 threads per applicable standards. Apply an appropriate cutting fluid for the workpiece material to extend tap life and improve thread finish. Back the tap off periodically to break chips when tapping blind holes. Discard the tap if any chipping or cracking is observed on the cutting edges to prevent workpiece damage.