The main problem of the choice of a knife is the stiffness of the knife, which should be prevented or eliminated as much as possible. The main points of consideration are as follows;

1. Choose the diameter of the large inverted rod as much as possible, close to the diameter of the pores.

2. Choose a short knife arm (working length) as much as possible. When the working length is less than 4 times the diameter of the knife rod, you can use a steel knife pole. It is best to use a hard alloy knife rod when the processing requirements are high. When the working-length is 7-10 times the diameter of the knife, the small hole is made of a hard alloy knife, and the punching knife is poured. When the working-length is 7-10 times the diameter, a shock-absorbing knife is used.

3. The main corner is greater than 75 °, close to 90 °

4. Choose a coating -free blade variety to reduce the cutting arc radius and the tip radius.

5. The precision processing uses a positive cutting blade (front corner) blade and tool, and the rough processing uses a negative cutting blade (negative front angle) blade and tool.

6. When the depth is not through the holes, there must be cooling measures, and compressed air (gas -cooled) or cutting solution (chip and cooling) can be used.

7. Select the right, fast knife handle fixture.