Osg 1405009908 Thread Forming Tap 5/16-24 Unf Modified Bottoming

Product Description

The OSG 1405009908 is a thread forming tap in the EXOTAP VP-NRT series, designed for cold-forming internal threads without cutting or producing chips. Sized for 5/16-24 UNF threads, it features a modified bottoming chamfer with 2 to 2.5 chamfered threads, allowing it to tap close to the bottom of blind holes. Constructed from powdered metal high-speed steel (PM-HSS) with a TiCN coating, it delivers high wear resistance and extended tool life across a broad range of workpiece materials. Thread limit is H4, suitable for producing threads with controlled tolerance. This tap is installed by machinists and tool-and-die professionals in production and maintenance machining environments.

This tap is suited for blind hole threading applications in materials including alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. Its thread forming action displaces material rather than cutting it, resulting in stronger threads with improved surface finish. The EXOTAP VP-NRT series is engineered for use in CNC machining centers and conventional tapping machines where consistent thread quality in high-volume or demanding material applications is required. Right-hand thread direction applies throughout. No coolant-through capability is present, so external or flood coolant should be applied at the cutting zone.

Key Features

• Thread forming (chipless) design produces stronger threads than cut tapping by cold-working the workpiece material
• Modified bottoming chamfer (2 to 2.5P) enables threading close to the bottom of blind holes
• Powdered metal high-speed steel construction provides superior toughness and wear resistance compared to conventional HSS
• TiCN coating reduces friction and extends tool life in abrasive and hard materials
• H4 thread limit ensures consistent tolerance control for 5/16-24 UNF threads
• 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. Suitable for use in CNC tapping machines and conventional tapping equipment capable of handling 5/16-24 UNF thread forming taps.

Installation Notes

Thread forming taps require a properly sized forming tap drill hole, which is larger than the drill size used for cut taps - consult a forming tap drill chart for the correct hole diameter before starting. A licensed machinist or tooling professional should verify spindle speed and feed rate settings per the machine tool and workpiece material before use. Apply cutting or tapping fluid rated for the workpiece material to reduce heat buildup at the tap-workpiece interface. Inspect the tap for wear or deformation before each use, as overloading a forming tap in a blind hole can result in tap breakage and workpiece damage.