Kennametal 1871016 CPMT3251LF KC5010 Carbide Turning Insert

Product Description

The KENNAMETAL 1871016 is a solid carbide turning insert with ANSI code CPMT3251LF and grade KC5010, designed for precision metal removal in turning, facing, and boring operations. The insert features a TiAlN coating applied via PVD process, delivering high wear resistance across a range of workpiece materials. Key geometry specs include an 80-degree diamond (rhombic) shape, a 3/8-inch inscribed circle, a 1/64-inch corner radius, and a positive rake angle of 5 degrees with an 11-degree relief angle. The LF chip breaker is optimized for finishing and light machining passes. This insert seats via screw-on holding and offers two usable cutting edges per insert.

This insert is suited for finishing and light machining applications on steel, stainless steel, cast iron, superalloys, and titanium (ISO material codes P, M, K, N, S). It is appropriate for both residential shop and industrial production environments. Typical applications include CNC turning centers and manual lathes where a screw-on CPMT-style insert holder is in use. The maximum depth of cut is 1.25 mm (0.0492 inches), making it best suited for light finishing passes rather than heavy stock removal. Tooling engineers and CNC machinists working on tight-tolerance finish cuts will find the honed cutting edge and positive geometry well matched to this type of work.

Key Features

• KC5010 grade with TiAlN PVD coating for high wear resistance on steel, stainless, and cast iron
• 80-degree diamond (rhombic) insert shape provides a strong cutting edge with versatile entry angle options
• LF chip breaker geometry engineered for finishing and light machining operations
• Positive rake (5 degrees) and positive side clearance reduce cutting forces on difficult materials
• Screw-on holding method with 0.1732-inch hole diameter for secure, repeatable seating
• Multi-use insert suitable for turning, facing, and boring in a single geometry

Compatibility

Designed as a screw-on CPMT-style replacement insert conforming to ANSI insert code CPMT3251 and ISO insert code CPMT09T304. Compatible with tool holders designed for CPMT 3251 screw-on inserts. Verify holder pocket geometry and screw size before installation.

Installation Notes

Insert installation should be performed by a qualified machinist or tooling technician. Power down and lock out the machine spindle before seating or removing inserts. Use the appropriate Torx or hex key to tighten the clamp screw to the holder manufacturer's specified torque — do not overtighten, as this can crack the carbide. Inspect the insert pocket and seating surface for chips or debris before installing a new insert to ensure proper seating and edge repeatability.