How to reduce the height of residual spine?

One feasible method is to reduce the step distance and decrease the distance between adjacent cutting paths. But this means an increase in the number and density of cutting paths per unit area, and an increase in precision machining time.

Another feasible method is to use larger cutting tools. Because the larger the radius of the tool, the greater the curvature at the contact point with the material. At the same knife path density, the residual ridge height obtained is about smaller. Using large radius tools can reduce the height of residual ridges and achieve better surface quality, but many parts that require precision machining have narrow gaps and cannot be processed with large radius tools.