Machining Impossible Shapes

This paper discuss the state ofthe art technology in duplicating an existing mold or die using digitized data from Optical scanners, instead of using traditional "copy milling". Both the technical results and experience from the process to achieve these results are expressed. The main process is discussed highlighting the benefits of using new technology versus copy milling or from surface. The main process consists of : 1) Scanning: An existing mold or die is scanned using Optical scanners. The software and hardware used to scan the die/mold are described in detail with the advantages of using Optical scanners versus laser scanners. 2) Data preparation: Once the die/mold is scanned, the data is pre-processed to read to any CAD/CAM systems. An STL (Steriolithography format) file is created for cutterpath generation and section lines are created, in case if surface development is required, for other applications. 3) Creating toolpaths using CAM software : Major issues in cutting the scan data are discussed. 4) Cutting p-20 steel on CNC mlc 5) Quality Check: Checking the die/mold with the following procedures a) CMM machine, b) Using the same scanner. In this process, we compare the dimensional accuracy of duplicated die/mold with original die/mold using Optical scanners and CMM machines. We cut one die for Chrysler Corporation using the above process and the results are very impressive.