One of the most crucial parts of manufacturing is fixing the workpiece. Proper fixturing enables accurate machining, assembly, etching, etc. Most modern fixturing devices are static and difficult to adapt to varying workpieces. This letter introduces a new concept for a fixturing device–the SIMJig–that automatically adapts its structure to fix a given workpiece. Custom fitting the jig clamps to a workpiece can greatly improve the stability and accuracy of the manufacturing process. Reconfigurability is achieved by a unique clamp and gear design, as well as one of two optional external driving mechanisms. In total, the SIMJig only uses three actuators to control multiple clamps. The design of the SIMJig, as well as the two external drivers, are fully detailed. The method of operation is described, along with explanations of how the SIMJig is initialized. Two algorithms are presented that detail how the clamp configuration is derived from the workpiece model, and how the SIMJig derives the optimal reconfiguration scheme to achieve the clamp configuration. The SIMJig doubles as a turntable, which allows it to collaborate with robotic arms to vastly increase their workspace. This is illustrated for a notoriously difficult task of gasket insertion, using the SIMJig and two robotic arms.