Becasue Statasys is the only producer of the FDM technology, the entire process is very standard. Stratasys has designed an easy to use interface that the engineer can use from their own workstation.
After a .STL file is created in a CAD software, an applicationknown as QuickSlice is run on the design. Quickslice mathematically slices and orients the conceptual model into horizontal layers for the build process. This program incorporates the SupportWorks program, also developed by Stratasys, that designs the necessary supports needed for building the part. The software is also capable of accuratly scaling the designs so that multiple parts can be built simultaneously or within the confines of the production space of the machine. These programs process the design on a workstation and also serve as the interface with the actual machine. The information from these programs is finally sent via LAN to the machine for production.
Once the machine is activated, it calibrates itself automatically to account of for any movement that has occurred since its last manufacture. Once the design has been transferred, the thermoplastic is heated to 1 degree F above the materials melting point and sent through a pressurized channel to a pump. While this is happening, the extrusion head (moving in the X-Y axis)and platform (moving in the Z axis) are moved into their respective starting positions. NOTE: In order to reduce erros in manufacture and increase production speed, the machines are not belt and gear driven like most other prototyping equipment. Instead the devices are electro-magneticly driven thus reducing friction and shaking due to outside movement The extrusion head then begins to release the material onto the platform which is vacuum. The material, which is vacuum held in order to further reduce movement solidifies within 0.1 seconds after leaving the extrusion head. After a layer is pored, the platform moves to the next position and the material is pored again. This continues until the entire design is complete.
While the product is being made, the system monitors the position of the extrusion head, and any sort of interference that occurs to maintain repeatability. Once the part is made, the user is notified at their workstation, the vacuum hold is released, and the platform slides out of the machine for easier removal of the part. This entire production process occurs within a matter of minutes to a few hours to complete making FDM a very rapid prototyping process.
