PartMaker Software for programming CNC mills, lathes, wire EDM, turn-mill centers and Swiss-type lathes offers a full machine simulation module. This allows the programmer to view a photo-realistic 3D model of the machine that will be producing the part. This simulation module provides improved error checking and collision detection by allowing users to perform a more thorough machining simulation. The machine model being simulated incorporates machine-specific toolholders and attachments for detecting possible collisions. The ability to detect such problems off-line, on the user’s PC, allows users to spend less time in setting up new jobs and performing dry runs to assure that there are no collisions on the machine.