Osg 1207100 Spiral Point Tap 5-40 Unc 2 Flute Hss

Product Description

The OSG 1207100 is a spiral point tap designed for threading 5-40 UNC holes in a range of metallic materials. Built from high-speed steel with a bright finish, this bottoming chamfer tap is suited for threading close to the bottom of a blind hole where maximum thread engagement is required. It carries an H2 thread limit and a 2B/3B class of fit, making it appropriate for standard commercial and precision thread applications. With 2 flutes and right-hand threading, the spiral point geometry pushes chips ahead of the cut, keeping the flutes clear during the tapping operation. Overall length is 1.938 inches with a thread length of 0.323 inches.

This tap is used in manufacturing, machining, and maintenance environments where 5-40 UNC threads are required. Typical applications include tapping aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, high-carbon steel, and hardened steel. It fits standard machine tapping setups and hand tapping operations where a bottoming chamfer is specified. The 0.141-inch shank diameter is compatible with standard tap holders for this size range. It is commonly used by machinists, toolmakers, and maintenance technicians across production and job-shop environments.

Key Features

• Bottoming chamfer for threading close to the bottom of blind holes
• H2 thread limit with 2B/3B class of fit for standard and precision thread tolerance
• High-speed steel construction suitable for a broad range of ferrous and non-ferrous materials
• Spiral point geometry pushes chips forward, reducing clogging during through-hole and shallow blind-hole tapping
• Bright finish with no coolant-through requirement, compatible with standard cutting fluids
• Right-hand thread direction, non-oversize, non-interrupted thread form

Compatibility

Designed for cutting 5-40 UNC threads in aluminum, cast aluminum, cast iron, low-carbon steel, medium-carbon steel, high-carbon steel, and hardened steel. Compatible with standard tap holders sized for a 0.141-inch shank diameter.

Installation Notes

This tap is installed by qualified machinists or toolmakers using standard tapping equipment or a tapping handle. Ensure the workpiece is securely fixtured and the correct pilot hole diameter for 5-40 UNC is drilled before tapping. Use an appropriate cutting fluid for the workpiece material to extend tool life and improve thread finish. When tapping blind holes with a bottoming chamfer tap, advance carefully to avoid bottoming out the tool against the hole floor under power.