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This model is
very loosely based on the Meccano Super Model leaflet Number 29
published in 1934, the cover of which is shown above. The model is one
of only a handful of designs Meccano published that used part no. 167
the geared roller bearing. This was the largest and most expensive part
produced by the company. Introduced in 1928 it was never a big seller,
priced at £1.00 it was a very expensive part. Most of the
published plans using the G.R.B. were in fact reworking of models
designed earlier that used a roller bearing made up from part No. 119
channel segment. Production of the G.R.B. ended with wartime
regulations in 1941 along with that of all other Meccano products. The
G.R.B. was unfortunately not in the range of parts when production
resumed in 1945. The one I used on the crane is a modern
reproduction made by Ashok Banerjee and finished in 1950s red and green .
I did intend when I started construction to build the model as
illustrated but decided the design of the boom was too simplistic
compared to the prototype cranes. In fact the "L outfit" had many more
parts than the instructions used and a much better model could have
been designed. My model is not a scale model but based on the
proportions of the original Meccano model and various pictures of the
original cranes. I also borrowed the basic design and construction of
the boom from Bert Love's Electric Dockside Crane published in The
Meccano Magazine, in two parts, July and October 1978. The main
difference being I continued the double bracing throughout the entire
length of the boom. This is balanced with 1.5 kg. of cast lead weights.
The model is driven by three electric motors, one for each of the
movements, Slewing, hoist and crab trolley. Again I followed Bert's
design for the hoist and trolley. The slewing movement is driven by a
Swiss Escap motor with built in reduction gearing driving
directly through connecting drive shafts to the spur gear rotating
around the geared roller bearing. The motive power of the
original cranes would also have been electric motors.

The prototypes of this type of crane were built between the
1900s - 1970s and can still seen be at navel dockyards and ship
builders around the world. Although referred to as "Hammer Head Cranes"
the more correct term would be a "Giant Cantilever Crane". There
are fine examples on Clydeside, Cowes, Halifax Nova Scotia and Sydney
Australia. They were designed to be used for very heavy lifting during
the
fittingly out and repair of large ships. Many of the cranes were
capable of
lifts of over 250 tonnes. Their use was some what restricted as they
were
built in a fixed position on the dock side. The black and white picture
(right)
is
the Govan shipyard crane, Glasgow one of five cranes of this type on
the Clyde.
The colour photograph above is of the
250
tonne hammer head crane at the Captain Cook dry dock in Sydney.
The
crane took six years to build and was completed in 1952. The main boom
is 83 metres (273 ft.) long. The tower is 43 metres (141 ft.)
high from dockside to the underside of the boom and is 15.25 metres (50
ft. ) square. The tower rests on foundations 27.4 metres (90 ft.) below
the sea bed. During the trial erection, the cantilever boom
was assembled upside down this was done to avoid the great deal of
shoring that would have been necessary because of the tapering of the
cantilever. I built the boom in the same way on my model.
I shot the picture in the early morning
of March 19 2002 on the first day of an Australian vacation.
The crane on the left is the 80 ton crane at Cowes on the Isle
of Wight. The crane was designed and engineered by
Babcock and Wilcox in 1911 and was the only crane of this type they
ever built.
It is one of the earliest cranes of this type still existing. I took
the photograph in the late afternoon, April 2005.
The picture below is from a wartime publication
"Britain's Merchant Navy" circa
1943 and shows a hammer head crane at a fitting out yard where
pre-fabricated (Liberty) ships were assembled.
For more
information about The
Cowes Giant Cantilever Crane click here.

The completed Meccano crane pictures were taken January 21 2004
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