5. Built-up edge. Built-up edge leads to poor machining finish, and when the built-up edge falls off, it causes edge cracks.

Reason 1. Cutting speed is too low. Solution: Increase cutting speed,

Reason 2. The blade has a negative rake angle. Solution: Use positive rake angle inserts,

Reason 3. The workpiece material is sticky. Solution: ① Use coolant and increase the flow rate or use no coolant. ②Use coated blades. ③The blade surface is polished.

6. The cutting edge is broken. Small chipping of the cutting edge results in poor workpiece finish and excessive flank damage.

Reason 1. The feed is too large. Solution: Reduce the feed and blunt the cutting edge.

Reason 2. The rear angle of the blade is not suitable. Solution: Adjust the rear angle.

Reason 3. The blade grade is too brittle. Solution: Choose a stronger grade.

Reason 4. The chip breaker is too narrow or the end chip breaker is too close to the cutting edge. Solution: Choose a wider chip breaker geometry or adjust the position of the chip breaker.

Reason 5. There is oxidation or hard skin on the surface of the workpiece. Solution: Adjust processing parameters.

7. The blade is broken. Not only will it damage the blade, but it will also damage the tool pad and workpiece.

Reason 1. There is oxidation or hard skin on the surface of the workpiece. Solution: Reduce the machining clearance angle.

Reason 2. The cutting edge is broken. Solution: Reduce feed and/or depth of cut.

Reason 3. The cutting load of the blade is too large. Ending plan: Choose a tougher blade grade.

Reason 4. The blade grade is too brittle. Solution: Single-sided fluted inserts or large sizes.

Reason 5. The blade size is too small. Solution: Strengthen the tool bar.

Reason 6. The tool bar is not strong enough and is bent. Solution: Check the clamping.

Reason 7. The blade or tool holder is not clamped well. Solution: Replace the blade in time.

8. Blade tip wear. There is a lot of wear behind the rounded corner of the blade tip.

Reason 1. The tool tip fillet is not strong enough. Solution: Increase the blade fillet radius or change the shape.

Reason 2. The blade brand has poor wear resistance. Solution: Blunt the cutting edge or choose a more wear-resistant grade.