CNMG 120408-TM OS8225 Carbide Turning Insert

The CNMG 120408-TM OS8225 is a negative-rake carbide turning insert designed for medium machining on CNC and conventional lathes. With its 80° rhombic geometry, strong cutting edges, and 0.8 mm corner radius, this insert offers stability and reliability during roughing and finishing operations. The larger nose radius improves tool strength and allows for higher feed rates while maintaining surface quality.

Manufactured in the OS8225 grade, this insert delivers a balanced combination of toughness and wear resistance. The TM chipbreaker provides efficient chip evacuation, reduced cutting forces, and improved surface finish, even in steels and stainless steels. This makes it suitable for a wide range of medium machining applications.

The CNMG 120408-TM OS8225 is compatible with standard external turning holders such as MCLNR, PCLNR, and DCLNR, ensuring secure clamping and versatility in different setups. It is commonly applied in automotive, general engineering, and mold manufacturing, where productivity and durability are essential.

Code Breakdown:

• C – Insert shape: 80° rhombic

• N – Clearance angle: 0° (negative rake)

• M – Tolerance class (medium)

• G – Insert with hole and chipbreaker

• 12 – Insert size: 12 mm

• 04 – Insert thickness: 4.76 mm

• 08 – Corner radius: 0.8 mm

• TM – Chipbreaker for medium machining

• OS8225 – Grade optimized for steels and stainless steels

Key Features:

• CNMG-style 80° rhombic turning insert

• Size: 12×12 mm, thickness 4.76 mm, radius 0.8 mm

• Grade OS8225 – carbide with balanced toughness and wear resistance

• TM chipbreaker for efficient chip control and good finish

• Negative rake geometry for strength under load

• Fits holders: MCLNR, PCLNR, DCLNR

• Ideal for medium machining of steels and stainless steels

Grade Information (OS8225):

• Coating: PVD, copper color

• Application: general milling and turning of steels, stainless steels, cast irons

• Best for: stainless steel turning and milling

• Material hardness: HRC <30

• Cutting speed: 120–220 m/min