We present an outline of a self-replicating machine concept that utilises in-situ resources on the Moon with which to construct itself - this represents the ultimate bio-inspired system. In attempting to deal with the practical engineering issues with such a machine, there are a number of biomimetics lessons to be learned, the most important being the requirement to synthesise itself from local raw materials. The self-replicator may be envisaged as a mobile rover mounting a suite of 3D printers, drills, etc - this bears similarities to the upcoming Resource Prospector mission to the Moon to demonstrate in-situ resource utilisation. 3D printing of mechatronic components will be key to 3D printing of robotic machines. It will be partially demonstrated that electric motors and neural circuits can be 3D printed. On the assumption that almost any functional structure can be 3D printed, 3D printing motors and electronics constitutes a demonstration of universal construction capability.