Osg 1405010008 Thread Forming Tap 5/16-24 Unf Modified Bottoming

Product Description

The OSG 1405010008 is a thread forming tap designed for producing 5/16-24 UNF internal threads in blind holes without generating chips. Built from powdered metal high-speed steel (PM-HSS) and finished with a TiCN coating under the EXOTAP VP-NRT series, this tap cold-forms threads by displacing material rather than cutting it, resulting in stronger thread walls and longer tool life. The modified bottoming chamfer with 2 to 2.5 chamfered threads allows threading close to the bottom of a blind hole. Overall length is 2.719 inches with a 0.318-inch shank diameter. Machinists and tool-and-die specialists install this tap in CNC machining centers, drill presses, and tapping machines.

This tap is suited for blind hole threading operations in precision machining environments, including production shops and job shops. The H5 thread limit and Class 3B fit designation target applications requiring close-tolerance threads. The right-hand thread direction and standard UNF profile make it a direct fit for fastener-thread production in components machined from alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. Tapping depth reaches 1.126 inches, making it practical for moderate-depth blind holes common in structural and mechanical assemblies.

Key Features

• Thread forming design displaces material rather than cutting, eliminating chips in blind holes
• Powdered metal high-speed steel construction provides uniform grain structure and improved wear resistance over conventional HSS
• TiCN coating reduces friction and extends tool life across a broad range of workpiece materials
• Modified bottoming chamfer (2 to 2.5P) allows threading close to the bottom of a blind hole
• H5 thread limit with Class 3B fit for close-tolerance UNF thread production
• Compatible with alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces

Compatibility

Designed for blind hole threading in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces requiring 5/16-24 UNF internal threads at a Class 3B fit. Part of the OSG EXOTAP VP-NRT series (Series 14050).

Installation Notes

This tap is installed by a machinist or tool-and-die technician using a tapping machine, CNC machining center, or manual drill press equipped with a tapping attachment. Ensure the correct tap drill size for thread forming is used prior to tapping, as forming taps require a larger pilot hole than cutting taps for the same thread size. Apply appropriate tapping fluid or cutting oil for the workpiece material to reduce friction and heat buildup. Secure the workpiece firmly and confirm spindle alignment before beginning the tapping cycle to avoid tap breakage.