Computer Aided Modeling

Computer Aided Manufacture (CAM)

CAM uses computers to automatically control the machinery performing various manufacturing processes.

Computer Numerical Control (CNC): A CAM technology using computers to control cutting machines such as milling machines to cut specified three-dimensional shapes. CNC has been used since the early 1970s. You'll notice the milling maching in the photo (left) is a 4-Axis machine that removes material via its milling spindle to create a 3-dimensional model.

Another popular technology associated with CAM is 3D printing. A layer manufacturing technology in which the layers are formed by using a printhead-like device to distribute an adhesive to bond the surface of a powder in the desired shape. (photo right)

This process uses stereolithography technology to slice a computer model into hundreds or thousands of very thin slices that the printer will build layer upon layer until the piece is complete.

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Similarly, another technology that relies on stereolithography to create models is based upon the principle of Photopolymerisation.

A photopolymer is a polymer that changes its properties when exposed to light, often in the ultraviolet spectrum.

Like a 3D printer these machines create a model layer by layer until complete. The resolution for this process is higher and is often the choice for intricate or very fine designs.(polymer models left)

A 3D printer builds the layers on top of each other starting with a baseplate. A  machine that uses photopolymers builds the model upside down with each layer emerging from a pool of polymer. 

There are advantages and disadvantages for each of these technologies. Cost and speed can play a vital role role in selecting which technology to use for each design. A very simple but larger design may work more efficiently with a CNC mill where a very intricate pattern may be best for a photopolymer.