Frequent contributor Raymond Rizkallah sends us this nice little routine that contains two functions for performing a slice operation on 3D objects. Start by loading the LISP file, then use the function SLC to perform a single slice by picking a line or two points. The line (or two points that define a line) is projected to make the cutting plane, and both parts are retained. If you want to slice the object using multiple lines, use the function SLCM, which will let you select multiple lines that are also projected to make cutting planes, while retaining all parts.