Patent ID: 6997698

Claim:
A system that executes a process to create three dimensional products, the system including a plurality of subsystems, wherein: each of the subsystems is configured to: perform one of a first subset of N 1 of a plurality of stages of the process by printing products layer by layer, where N 1 is greater than 1; and to change the stage of the subset being performed on receipt of a change instruction; in the event that one of the subsystems fails, at least one of the remaining subsystems is configured to synchronously change to performing the respective stage of the failed subsystem without requiring transfer of data relating the respective stage to the said at least one remaining subsystems; and when a subsystem changes to performing a different stage, the system is arranged to reconfigure the subsystem to be capable of performing a second subset N 2 of the stages, where N 1 and N 2 have the same number of stages.