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A ‘floating’ Meccano crane

The compound Meccano ball bearing unit on which the heavy superstructure revolves. Right: The Meccano model is faithful to the original in scale and appearance. Photos: Joseph N. Attard

The compound Meccano ball bearing unit on which the heavy superstructure revolves. Right: The Meccano model is faithful to the original in scale and appearance. Photos: Joseph N. Attard

A crane built in 1915, and which can still be seen today in the port of Genoa, was recreated using a popular model reconstruction system

Joseph N. Attard with the model crane in its elevated position.Joseph N. Attard with the model crane in its elevated position.

Sometimes events combine to make us eat our words. In June 2010, I thought that it was reasonable to write Enough Cranes in the prestigious hobby magazine Constructor Quarterly. Besides a number of smaller Meccano models, I had already built two large crane models; but fate decreed otherwise.

While on a cruise in the Western Mediterranean, I took a tourist ferry ride around the port of Genoa (incidentally, the cruise was on the ill-fated Costa Concordia). Coming round a headland in the harbour, there loomed a majestic floating crane. I took a series of photos of it but soon forgot all about it.

Once back home, I realised that crane was very similar to the one I had photographed in the Panama Canal in 2004. A bit of research revealed that these two cranes had been built by the same company. The Genoa crane was built by Demag of Duisburg way back in 1915. It was first put into service in the port of Bremerhaven, Germany, where it was used for heavy lifting in the fitting out of such ships as the famous Graf Spee and Tirpitz. At the time, it was the largest floating crane, and was even depicted on German bank notes. After World War I, the British claimed the crane in reparation, but faced with the difficulty of transporting it to Britain, they left it in Wilhelmshaven.

After surviving two World Wars, in 1945 the crane was taken over by the US Navy, again as war reparation, and was used extensively in the recovery of war wrecks. The two original 1000HP steam engines were replaced by four diesel engines in 1955, and subsequently the diesel-electric plant operated all crane movements. Between 1958 and 1980 the crane was used by the Federal Republic of Germany, but mounting running and maintenance costs forced the return of the crane to the Americans.

The main attraction of a serious Meccano model lies in it working as closely as possible to the original

In 1985, the crane was sold to an Italian company, which transported it from Bremerhaven to Sardinia on a 10,000-ton barge towed by tug boats. In 1990, it was again sold to a private owner, who took it to Genoa for work on the construction of new ships. Finally, in 2002, it was declared by the Italian government as a “Monument to Industrial Archaeology”.

The large floating crane, known as the Langer Heinrich (Long Henry), in Genoa Harbour.The large floating crane, known as the Langer Heinrich (Long Henry), in Genoa Harbour.

Works to restore it to its former glory were initiated in 2005. These included the replacement of much corroded steel structures and thousands of steel rivets. A general refit was carried out, and a lot of fittings such as pipes, cables, etc, which had badly deteriorated over a period of 90 years were replaced or refurbished. After three years of intensive work, in 2008 it passed its test by lifting 275 tons, thus obtaining a five-year certificate to operate at its design maximum of 250 tons. It is due for retesting this year.

Some technical data for the crane: the crane floats on a 50 by 30-metre self-propelled pontoon, which is divided into 41 compartments, many of which can be individually flooded for counterbalance. The jib towers 84 metres when fully raised, and 56 metres when lowered. The crane superstructure can be turned through 360 degrees. Two side-by-side hoists lift 250 tons in combination, with a further hoist at the tip of the jib lifting 50 tons. A smaller 20-ton hoist runs on a trolley under the jib. All movements are controlled from an operating cabin high on the main tower. Most of the control systems are original, including a gravity-operated mechanical inclination indicator in the operator’s cabin which gives an audible bell warning if inclination is over four degrees. No electronics here! The crane has a deadweight of 2,393 tons.

Little by little, I started to be attracted by the idea of modelling the crane in Meccano. The original blue prints of the crane had been destroyed during the war. Thus, the series of high-resolution photos which I had made proved to be crucial in determining much of the smaller details of the crane. As an example, the numbers and paths of the hoisting wire ropes from the machinery rooms to the various pulley blocks could only be correctly determined through these photos, and that only with great difficulty after repeated study of the blown-up pictures. The counterbalance, a massive block (estimated at over 100 tons) rolling up and down the back of the main tower, was a novel and challenging feature to replicate.

So, where to start? Luckily, I found scale drawings of the crane’s main structures on the internet, and it was thus possible to work out all other principal dimensions. Scale has to be respected as much as possible if the result is to look realistic; for this model, a scale of approximately 48:1 was established.

The crane essentially consists of three main rigidly built substructures: the pontoon with its fixed pyramid-shaped support tower; the central ‘bell’ section, including machinery housings, which fits on, and rotates about, the said tower; and the jib. The pontoon and fixed pyramid tower were constructed first. The real crane revolves on a massive taper roller bearing, estimated from old fuzzy pictures to be about four metres in diameter, with a central shaft six metres long. It proved to be very difficult to replicate this in Meccano, but eventually I built a sufficiently strong roller bearing out of real Meccano parts.

Next came the construction of the “bell”, which is the part revolving around the tower fixed to the pontoon, and which also carries the machinery rooms and the counterweights. Suffice it to say that very small tolerances had to be allowed so that the superstructure turns easily on the top bearings. The jib was then constructed, with four tapering main members as in the prototype.

The main attraction of a serious Meccano model lies in it working as closely as possible to the original. So now I set about replicating all the relevant machinery. Without going into unnecessary detail, every movement of the crane is operated by a separate small motor through appropriate reduction gearing. There are six independent movements: the three hoists, the running small hoist carriage, the lowering and raising of the jib (called luffing), and the revolving of the whole superstructure. The six motors are remotely controlled by a hand-held switch box. The rising and falling counterweight is made out of scrap lead which I melted down into a scale cuboid. Guided by rollers, this block rises and lowers by means of two screwed rods.

A lot of thought was given to all the crane’s various speeds. A compromise had to be reached between the actual speeds of the original, and the realistic speeds for a model. Not too fast, but neither as slow as perhaps is strictly correct but which would have spectators yawning. As an example, one revolution on the original crane took up to eight minutes, and jib luffing could last 17 minutes!

Finally, the three main sub-assemblies were brought together.

An epilogue to this saga was unexpectedly provided by nature. I had taken the model out on to the roofed open terrace where I do most of my photography in natural sunlight. I thought it was safe to leave it overnight, covered by a plastic sheet against the dew. But an unexpected very heavy storm during the night flooded half of Malta. The model was drenched throughout. Hours spent wiping, oiling, blow-drying was not enough to prevent many bolts from rusting.

Well, what do you expect out of a model of a 100-year-old crane?

• The model can be seen in action on You Tube at www.youtube.com/watch?v=jR8yRlS8qpU For more information about the crane’s history and restoration visit www.langerheinrich.it/it/index.php or www.colsub.it/ video.php?id_video=99

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