I made a wooden barge for my tugs to pull but found this too heavy so I asked my old firm to make me one in 4mm aluminium it has been fully seem welded and is water tight .I got them to powder coat the whole barge in black matt and I just added the red paint. The top just slides off so I can change the cargo I just wish that I had not made this so deep as it sits high in the water unless I add a load of ballast am using a 10 ltr water container at the min and its still work in progress