As in 2.5D operations, SolidCAM makes extensive use of rest milling in 3-axis operations. Rest material machining is accomplished on either block stock or a 3D cast model. Machining only occurs where rest material is detected. Automatic rest machining has become common practice in all aspects of machining, but it is extremely important in machining of complex parts. This permits removing material left behind as a result of tools being too large to reach into corners, valleys, depressions, etc. In rest machining, a smaller cutter is selected, but the toolpath is re-computed and machining only occurs in those areas in which material remains.
In 3D operations within SolidCAM, the rest material is determined from an in-process model that is generated with each cutting pass. The amount of stock remaining is automatically updated after each machining sequence. From the in-process model, the software can establish the depth of material at any point on the surface by comparing the in-process model to the final model of the part. The 3D in-process model also includes the 2D areas of a part. SolidCAM uses the difference between the stock and target model to optimize subsequent toolpaths on the 3D model. Within a dialogue box a user can select whether machining should be done across the entire part or only where material remains from a previous cut.
