Special purpose machines are designed and built for a variety of purposes which include assembly, forming, material removal, packaging, testing or combinations of these and other operations. A typical special machine application is for the finish machining of carburettor body castings. A special machine of this type would consist of a variety of "stations" to automatically position, mill, drill, tap screw threads, deburr and perhaps perform a final inspection or test of the finished part. Special machines often use conveyor systems to transport parts from station to station.

The automotive industry is one of the biggest users of special machines. Connection rods, carburettors and oil filters are among the many products that are machined or assembled on this type of equipment. Special machine builders use all of the skills of the toolmaker, plus a thorough knowledge of electric motors, hydraulics, gear drives and wiring.
Assembly and testing systems are often applied in highly regulated medical device manufacturing environments