Difference between orthogonal and oblique cutting

Orthogonal Cutting :-

Orthogonal cutting is a type of cutting in which the cutting tool is perpendicular to the direction of tool motion. In this cutting, the flow of chip is perpendicular to cutting edge. The tool has lesser cutting life in this type of cutting.

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In Orthogonal cutting, the direction of flow of chip is perpendicular to the direction of movement of cutting edge.

Oblique Cutting :-

Oblique cutting is a type of cutting in which cutting tool is at an oblique angle to the direction of tool motion. In this cutting, the flow of chip is not perpendicular to cutting edge. The tool has greater cutting life as compared to orthogonal cutting.

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In Oblique cutting, the direction of flow of chip is not perpendicular to the direction of movement of cutting edge.

The main difference between orthogonal and oblique cutting is that in orthogonal cutting, cutting edge of tool is perpendicular to the direction of motion but in oblique cutting the cutting edge make an angle with direction of motion.

Apart from this , there are other difference which are stated below :-

S.No	Orthogonal Cutting	Oblique Cutting
1	The cutting angle of tool make right angle to the direction of motion	The cutting angle of tool does not make right angle to the direction of motion
2	The flow of chip is perpendicular to cutting edge.	The flow of chip is not perpendicular to cutting edge.
3	The tool has lesser cutting life.	The tool has higher cutting life.
4	The shear force per unit area is high which increases the heat per unit area.	The shear force per unit area is low which decrease heat per unit area .
5	In this cutting, chip flow over the tool.	In this cutting, chip flow along the sideways.
6	In orthogonal cutting, surface fiish is poor.	In oblique cutting surface finish is good.
7	Cutting edge is longer than edge of cut.	Cutting may or may not be longer than edge of cut.
8	Two mutually perpendicular cutting force act on the workpiece	Three mutually perpendicular forces are involved .