After several days of building and mechanical tests, here is the (almost) Automatic Gantry Crane. Indeed, the inversion mechanism travelling the cabin required parts that I did not have and my version did not work well. So I opted for a simple reversing movement of the motor that proves conclusive, helped by my better control of the chain transmission. I kept the automatic hoisting which turned out to be very simple and smart. This is one of my biggest models MECCANO (although I had to lower the gantry of few inches for lack of bands and angle girders).