Positive and negative

First of all, decide whether positive or negative style inserts are going to be used.

A negative insert has an angle of 90° (0° clearence angle), while a positive insert has an angle of less than 90° (7° clearance angle). The illustration of the negative style insert, shows how the insert is mounted in the holder and tilted.

Some characteristics of the two insert types are listed below:


  • Single sided
  • Low cutting forces
  • Side clearance
  • First choice for internal turning and for external turning of slender components

Clearance angle


  • Double and/or single sided
  • High edge strength
  • Zero clearance
  • First choice for external turning
  • Heavy cutting conditions.

Clearance angle
​For more information, see the different applications in Choice of application.