I built this crane from one set M8, plus four extra motors (three sets 2.1 and one set 2.2) , one for each track, one for turning tower of the crane, one for beam , and one for hook (fifth motor comes with M8). Each motor comes with original control panel, but I did home made integrated panel for five motors in one box with ON-OFF-ON momentary switches. As power suply for the crane I use small 4.5V 1500mA DC transformer, so I can control all motors at the same time.
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