Sandvik Coromant 5961386 Threading Toolholder 5/8 in Shank

Product Description

The SANDVIK COROMANT 5961386 is a right-hand indexable threading toolholder designed for both internal and external threading operations on CNC lathes and turning centers. Part of the CoroThread 266 series, it accepts 266RL to 16 inserts secured by screw clamping. The shank measures 14.30 mm in height by 0.625 inches in diameter, with an overall length of 8.0 inches. Minimum bore diameter is 0.79 inches, making it suitable for threading in moderately tight bores. Coolant-through capability is built in, supporting chip evacuation and tool life in continuous threading cuts. The toolholder body is machined from steel for rigidity under the interrupted-cut loads common in threading applications.

This toolholder is used in production and job-shop turning environments where reliable, repeatable thread form on both OD and ID features is required. The 266RKF toolholder style is matched to the CoroThread 266 system, which is engineered for single-pass and multi-pass threading strategies on ferrous and non-ferrous materials. Typical install scenarios include gang-tool setups, turret-mounted configurations, and live-tool lathes where a compact, consistent threading unit is needed. The 3/8-inch insert inscribed circle provides enough cutting edge length for standard thread pitches encountered in general machining.

Key Features

• Accepts 266RL to 16 threading inserts via screw-clamp holding method
• Handles both internal and external threading from a single toolholder style
• Coolant-through design aids chip control and extends insert life during threading
• Steel body construction provides rigidity and dimensional stability under cutting loads
• 0.79-inch minimum bore diameter supports threading in restricted internal features
• 8.0-inch overall length with 1.875-inch head length suits standard turret reach requirements

Compatibility

Designed for use with 266RL to 16 series threading inserts within the SANDVIK COROMANT CoroThread 266 system. Insert inscribed circle is 3/8 inch (0.375 inches). Confirm turret bore and shank diameter clearance before installation.

Installation Notes

Installation is performed by a qualified machinist or CNC tooling technician. Ensure the machine is powered down and the turret is in a safe index position before mounting or removing the toolholder. Torque the insert-retention screw to the insert manufacturer's specification using the correct Torx or hex key — do not overtighten. Verify coolant-through port alignment with the machine turret coolant supply before engaging the coolant system.