prevention measures for chipping and breakage for small diameter end mills

Runout accuracy

Small-diameter end mills are easy to break due to their low rigidity. The main reason is the jitter of the tool itself and the impact of the jitter of the clamping tool. In order to prevent breakage, the runout accuracy must be strictly controlled. To this end, an effective method is to use a thermal expansion tool holder with high clamping accuracy to clamp the end mill.

Increasing the cutting speed to improve the cutting characteristics

Generally speaking, the cutting characteristics of the edge of the end mill cannot be fully utilized if the cutting speed is not reached. Even if the rotation speed of small-diameter end mills is increased, the cutting speed may not be sufficient. Especially for ball-end end mills, the actual cutting diameter is very small, so the cutting characteristics of the blade cannot be fully utilized in many cases. Therefore, when using small-diameter end mills, effective measures must be taken for the actual cutting speed.

Control the size change of the depth of cut

It is also important to avoid sudden loads on the tool. Especially at the corners, the depth of cut will increase, which will increase the load on the end mill. It is necessary to add a pre-processing procedure to make the depth of cut of the small diameter end mill uniform. Cycloidal tool trajectory can effectively balance the depth of cut. However, the cycloidal tool trajectory that moves on a circular arc path has a longer tool path and a correspondingly longer processing time than linear feed. Therefore, it is necessary to improve the cutting conditions to offset the extended processing time.