1. Bounce the knife, the strength of the knife is not too long or too small, causing the knife to bounce.
2. Improper operation by the operator.
3. Uneven cutting allowance (eg: 0.5 on the side of the curved surface and 0.15 on the bottom)
4. Improper cutting parameters (such as: tolerance too large, SF setting too fast, etc.)
1. The principle of using a knife: