This paper describes the conversion of an existing full-scale 5-ton payload crane into a semi-automatic “Handling Robo”. By its size, degrees of freedom, and mode of operation this crane resembles typical construction cranes, which can be enhanced in the same manner. The new control system allows operation of the crane in either a manual or a semi-automatic mode, and it can be taught to memorize up to 50 different benchmarks, i.e. particular points at the construction site, as well as safe routes among them. The major components of the system include: a programmable controller, three speed regulators, three encoders, several limit switches, a wireless remote control set, and a user-friendly MMI (Man-Machine-Interface). Most of the components can be installed externally in the vicinity of the crane's joints and inside the cabin, with minimal intervention in the original wiring. Following the physical retrofitting of the crane, a series of tests examined performance, accuracy, repeatability, and safety aspects. They demonstrated a 15-50% shortening of typical work cycles, high accuracy and repeatability, and a generally safer operation due to pre-tested paths and smoother movements with less sway and swing of the load.