Definition of blade rake angle:
- The insert rake angle is the angle between the top surface of the insert and the horizontal axis of the workpiece. It is defined as the direction angle of the tool rake angle to the reference plane (R).
- Positive inserts have a positive angle and Negative inserts have a negative angle.
The difference between Positive angle inserts and Negative angle inserts:
The main cutting edge clearance angle is the main difference between positive and negative angle inserts
Negative rake inserts have a 90° angle (0° clearance angle), while positive rake inserts have an angle less than 90° (7° or 15° clearance angle)
The easiest way to identify us:
The first letter in the insert code indicates the shape of the insert, while the second letter indicates the main cutting edge clearance angle.
- Taking CCMT060202 insert as an example, the second letter "C" represents that the main cutting edge back angle is 7°, which is greater than zero, so it is a positive angle insert.
- Similarly, taking CNMG120404 insert as an example, the second letter "N" represents that the main cutting edge back angle is 0°, so it is classified as a negative angle insert.At the same time, the second letter "N" represents that the blade material is CNC Lathe Cutter Carbide Inserts
- From this we can conclude that carbide inserts whose second letter is not "N" are called positive angle inserts.
Application of Positive angle inserts
Primarily used for finishing operations on CNC lathes. They are ideal for achieving a smooth surface finish on softer materials such as aluminum and brass. The positive rake angle helps reduce cutting forces, making them suitable for delicate or precision work.Less economical than negative angle inserts.
Application of Negative angle inserts
Negative carbide lathe inserts commonly used for roughing operations and cutting harder materials like steel or cast iron. The negative rake angle provides increased rigidity and tool stability, which is beneficial for handling higher cutting forces and achieving more aggressive cuts and have good economic benefits.
