Iscar 5990352 Threading Insert 6 Tpi Stub Acme Internal IC908

Product Description

The ISCAR 5990352 is a laydown threading insert designed for cutting internal Stub Acme threads. It carries the IC908 carbide grade with a PVD-applied TiAlN coating, suited for demanding threading operations across a wide range of workpiece materials. The insert produces right-hand internal Stub Acme thread forms at 6 threads per inch (TPI). With a 3/8-inch inscribed circle and a thickness of 0.143 inches, this is a precision carbide insert intended for use on CNC lathes and threading-capable turning centers. Machinists and tooling specialists in metalworking shops handling general, ferrous, non-ferrous, and exotic alloy components are the primary users.

This insert is applied in internal threading operations where a Stub Acme thread form is required. The Stub Acme profile is common in power-transmission components, lead screws, and linear motion assemblies where a reduced thread height is preferred over a full Acme form. The IC908 grade with TiAlN finish supports use across universal workpiece material groups, including steel, stainless, cast iron, non-ferrous metals, and high-temperature alloys, making it a broadly applicable insert for shops running varied material schedules. It is part of the ISCARTHREAD series.

Key Features

• Right-hand internal Stub Acme thread form at 6 TPI
• IC908 carbide grade with PVD TiAlN coating for extended tool life across multiple material groups
• 3/8-inch (9.53 mm) inscribed circle, 0.143-inch thickness — standard laydown insert geometry
• Compatible with universal workpiece material codes: H, K, M, N, P, S
• Conforms to ISO 13399 tooling data standards
• Part of the ISCARTHREAD series for consistent holder compatibility

Compatibility

Designed for use in ISCARTHREAD-compatible internal threading toolholders that accept the 16IR insert style. Specific holder compatibility should be confirmed against ISCAR tooling system documentation prior to ordering.

Installation Notes

Installation is performed by qualified machinists on CNC or manual turning equipment with threading capability. Secure the insert fully in the pocket with the appropriate torx or clamping screw before initiating a cut — never run the spindle with a loose insert. Verify holder bore clearance and thread-form geometry match the target workpiece specification before beginning the threading cycle. Follow the machine tool builder and insert manufacturer recommendations for cutting parameters; do not exceed the rated speed and feed range for the IC908 grade.