Rest Machining processes are used to find or modify the areas of the job where material remains after executing previous tool paths. Use rest finishing passes to machine rest material from corners of the job, not machined by a previous reference tool. The fillets produced by running the reference tool around these corners are re-machined using a smaller, target tool working on the rest area boundaries. Both tools must be of type BALL MILL. The reference tool must be larger than the tool that is used to cut the rest areas.

In shallow areas, the fillets are machined with passes along the fillet. In steep areas, the passes go across the fillet. You can control the step over in shallow areas and step down in steep areas independently. There may not be a constant step over in shallow areas because fillets have the same radius but can have variable widths. The passes, therefore, come closer together as the fillet narrows and get further apart where the fillet widens.