LONDON ZOO TROPICAL AVIARY CLOCK
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DESIGN
I
don’t usually live a jet set life, but I first called in at the zoo to discuss
the idea en route to the Makers Faire in San Fransisco. I’d sent in advance a
contraption I’d made in 1981 called Air
Raid. Two seagulls swirl around
overhead and shit polo mints when you press the fire button. This obviously
influenced the design for the zoo.
The
zoo’s offer had come from a wealthy sponsor who was already funding 50% of the
tropical birdhouse renovation. He had recently expressed interest in adding a
bit more to make it really special. Did I want to design something to tempt him?
I knew immediately that I did – I liked both the location and the theme (the
Victorians attitude to animals), but coming up with an idea was more tricky than
I’d expected.
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It didn’t have to be a
clock, but I like
clocks. People naturally gather to watch a performance on the
hour. Clocks are also fortunately too ‘nerdy’ to count as fine art.
My first idea was to make a clock in a cage, but I was quickly told that
this would not do – the zoo was busy removing cages and certainly didn’t
want any new ones, even if it was only a clock inside. I then started exploring
the rotating bird idea. I had a number ideas for mechanisms, scenes,
ingredients, but they obstinately wouldn’t distil into anything simple. At the
back of my mind was the Southwold pier clock
– which often isn’t working
perfectly, but as long as the boys trousers drop and they pee, the audience is
perfectly happy. At some point I realised that a unifying strand was birds
escaping, and this helped hone the design, but it still refused to reduce to
anything simple. |

Rejected caged clock idea
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One of many early designs
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Eventually,
with the deadline looming, my enthusiasm to do the job got the better of my
reluctance to submit a complicated design. I go through a cycle building
something really elaborate, and then relaxing with more straightforward stuff
for a while. The last project that had really stretched me had been my Mobility
Masterclass arcade machine three years ago so perhaps by now I was ready for the
next challenge. Anyway, the mysterious sponsor liked my crude animation of the
clock, so suddenly the job became a reality. I always feel flattered and keen
when a proposal is first accepted, and in this case my enthusiasm has continued,
so I guess I wasn’t such a bad design – even though I remain nervous about
its long term maintenance.
INFLUENCES |
Saul
Steinberg was an American cartoonist who most famously drew for the New Yorker
in the 1950s and 60s. My dad was a fan and his enthusiasm infected me. Most of
his work is now a bit dated but I’ve remained obsessed by one of his cartoons
depicting the American way of life in a Victorian setting. It portrayed the
state of the nation as an imposing pedimented statue, reminiscent of the Albert
Memorial in London. The idea of capturing the spirit of the age in this manner
really appeals to me. I tried my
own cartoon version a few years ago. Anyway, with Steinberg strongly in my mind,
the concept of a statue celebrating the victorian’s confidence about their
mastery over the animal kingdom seemed totally appropriate and appealing as a
project.

The 1951 Festival of Britain Guinness clock,
(note the toucans pecking the tree behind the doors)
In the late 1940’s a cartoonist called
Roland Emett was drawing ‘fantasy’ machines. He then started working with an
engineering company to make his cartoon machines into physical contraptions.
Guinness commissioned him to make a clock for the 1951 Great Exhibition,
featuring the Toucan they used in their advertising. The clock was a hit and
Emit made several more for English seaside resorts. The original London clock
was moved to Battersea Park and I vaguely remember being taken to see it as a
child and demanding to go back to see it again and again. I now can’t remember
what it looked like, but the connection between toucans and clocks is obviously
indelibly imprinted.

The entrance to Hagenbeck's zoo in Hamburg, c1910. Hagenbeck
was a flamboyant character who supplied zoos and circuses with wild animals and
native people. His zoo was the first to remove cages and build fake scenery and
mountains so the animals could be seen in their 'natural' habitat. The entrance
expresses the victorian confidence in their command of the natural world
perfectly.
AUTOMATA
AND FILM
The process of making a clock like this
is surprisingly similar to making a film. I’ve done both. Both tell stories.
Both start with research, followed by a broad outline to sell the idea. Once the
cash is agreed it’s a technical process of creating the material. Both are
finished by a process of editing, which with this clock involved programming all
the pneumatic rams and adding sound. The timing of each action is surprisingly
critical, get it wrong and it jars in the same way as a clumsy film edit. Both
film and clock involve disappointments and delightful unexpected surprises along
the way. Both only come to life right at the end of a long and expensive
process. The clock was certainly transformed by fine tuning the timings of the
rams and adding the bird sound track. I’d never expected the finished result
to feel emotional.
Personally, I prefer making a clock to a
film because the process of filming a scene is far more wearing and less
satisfying than making a part for a machine. Filming is frustrating because
it’s expensive and usually everything has to be done in a hurry. It usually
involves lots of people and lots of energy motivating them all to get the
result. I have done it and my films have been quite successful, but only on a
few special occasions have I ended a day filming feeling content.
In contrast, making parts in a shed is cheap, so
it doesn’t have to be done to a tight schedule, and there’s a satisfying
physical object to show for almost every day’s work. I know I’m a bit odd,
but I feel alive with the smell of the oily machine tools, the sparks of the
angle grinders and the white hot metal of the welding. To me it’s all much
more sensual, battling against physics and the elements to get the result. It
seems infinitely preferable to a hot film set, charming a group of people to get
the result. If I worked as a complete loner, I would feel limited, but I have
the luxury of working with a few other enthusiasts. And because there’s little
or no status attached to this sort of work, they only do it because they enjoy
it like I do.
INDUSTRIAL
AUTOMATION
Today, we are used to mass produced
machines which have all have been through many prototype stages and
modifications in production to make them reliable. It’s always really hard to
make a one-off machine reliable. Trying to make a first prototype 100% reliable
is virtually impossible. Sometimes my friend Will jokes that what we do for a
living is to make unreliable machines.
Fortunately we are not alone. A lot of
machines are built as one-offs, particularly for industrial automation. If an
industrial automation robot or conveyor system stops working a factory loses a
lot of money. Nothing is being produced but the factory is still paying the
staff and the overheads. In the UK, food factories spend in a particularly
extravagant style to fix their production lines as quickly as possible.
Unlike consumer machines, the long term
reliability of industrial machines is more important than initial price. Also,
industrial automation companies have to try and make it possible for engineers
to make reliable one-off machines using their stuff.
I like the industrial automation kit of
parts, and use them for almost everything I make. My machines are still pretty
unreliable to start with, but they usually settle down after a year or two and
then become at least manageable if not respectably reliable.
My enthusiasm often gets the better of me so my machines are usually far
too complicated and I sometimes have to go back to a machine twenty times to get
it to this state. (My ‘Expressive Photobooth’ was the worst ever – I went
back every week for two years, then rebuilt it and went every week for another
year….but then it was built round a PC (consumer product), not a
PLC(industrial automation product).
For people used to programming microcontroller
chips and making their own printed circuits the industrial automation kit must
seem ridiculously expensive and curiously old fashioned, as there’s no
soldering, the components all have screwed terminals and are connected to
astonishingly large DIN rail terminals. My control boxes are usually at least
600mm square, the one for the clock is 800mm by 1,000mm. But to me it seems
eminently sensible. Although I often solder my own printed circuit boards, when
I’m trying to get a complete machine to work I have to swap seamlessly from
software to hardware, a screwdriver is a more practical tool. If a control board
is too crowded, I can only see it clearly when its on the bench, not when its
installed in a machine in a typically awkward position. If
I need to add an extra wire, I simply pull the covers off the trunking and
screw it in place.
TECHNICAL
DETAILS
Pneumatics
I had the idea of using pneumatic rams
to drive everything early on, but at first wasn’t even sure if they would work
outdoors in all weathers. The rams are made of aluminium and stainless steel so
they would be fine but I wasn’t sure about the plastic tubing and flow valves.
My local pneumatics company assured me they had quite a few outdoor
installations so I went ahead. Apart from plastic being affected by UV there is
also the problem of condensation. The rapid changes of outdoor temperature means
a lot more water then normal gets sucked in. The problem is that if any
water reaches the control valves, it blocks up the tiny air passages and they
stop working. It is possible to buy refrigeration devices to remove all the
water, but these are expensive and bulky, so I was recommended a cheap
alternative which spins the air in a vortex, throwing the water out.
The pecking toucans
Having decided to use pneumatics, the
two main technical challenges were getting the toucans to peck the pendulum
reliably and getting the birds to fly and return to their cages without bumping
into anything. Industrial automation parts don’t solve problems like these
without some additional ingenious mechanical design. Both problems went though
several prototypes before finding solutions.
I first thought the toucans should each
have a string connected to a small ram to pull them back.
The string could pull when the pendulum was on the far side of its swing
and release when the pendulum touched the toucan’s beak. The result was that
the weight of the toucans would give the pendulum a nudge every swing. This is
the same principle as a gravity escapement (as used on Big Ben, and many other
tower clocks) so it seemed a good idea at the time. Sadly it was a complete
failure. It didn’t behave like a gravity escapement, more like pushing a child
on a swing. Pushing with any significant force shortens the period of the
pendulum’s swing. I eventually did get it to work by fixing the timing of the
pulls on the toucans’ strings, but still did not feel entirely confident about
it. As the timings were now coming from the logic controller, it was no longer
acting as a true pendulum, and this gave me the idea of fitting a small ram near
the top of the pendulum, giving it regular ‘pulses’ of air. This worked
first time, had easily enough power to nudge the toucans and was self starting.
So now it’s a complete fraud, the pendulum is a fake and its not even powered
by the toucans. But its reliable, looks great and makes a nice tick-tock sound.
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The Flying birds
There was no satisfying eureka moment in
getting the birds to fly and return reliably. My initial problem was that
the birds needed to be significantly bigger than my drawing to have any
presence when flying. This meant the wings would have to unfold. I tried
several unfolding and flapping mechanisms, but they all had problems. It
was during one of these tests that I tried the curved supporting rods with
the pivots on the rotating arm further out. This just looked great when
the birds were flying so it remained. The eventual solution for the wings was to
shape them so that they folded by themselves when they bumped into the
cages. I could then use their air supply, intended to power the wings, for
two cylinders on the ends of the arm. These pull the support rods inwards,
pulling the birds into their cages, so their normal position is just far
enough out to avoid all obstacles. I’m now amazed that they even seem to
work in quite a high wind without crashing into things. |
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Unexpected disasters always
happen. At one point we decided to cut down the plinth by 150mm. While lowering
the frame with a turfer, a rope slipped, dropping the clock hard and bending the
frame. We eventually straightened it by welding some short 100mm box section
pieces together to make a 'beam' which we used with a car jack to apply an
opposite force on the frame. How I would love to have a crane always ready in
the yard.
Near the end of the project I had a
software problem getting the clock to start at the right time every day and keep
good time – it just seemed very unpredictable. Logic controllers (like
computers before they were connected to the internet) just don’t keep accurate
time. The spec of my controller was an error of up to 45sec a month, about 10
minutes a year. It is bizarre that such sophisticated digital contraptions
can’t keep time – I used to think quartz crystals were almost as good as
atomic clocks but really they’re not much better than mechanical pendulums. I
was aware of this , so I had incorporated a cheap radio wall clock to correct
it, and it took a while to discover that this was the main source of the
problem. It had been struggling to get a strong enough signal, surrounded by the
metal clock frame and so was occasionally resetting itself, throwing everything
into confusion.
In the long term, I’m worried about the
lifespan of the valves and cylinders powering the pendulum. They have to do 10
million strokes a year! I’m also worried about the lifespan of the compressor.
Despite running everything at only 50psi, the clock uses a lot more air than I
was expecting and the compressor runs for 8-10 minutes every hour.
Postscript,
five years later:
After
the first few months I fitted a master valve which turns off the air supply to
all performance rams, except when performing. This greatly reduced the time the
compressor runs and its still going fine, currently 1500 hours since new. I
finally had to change the cylinders that work the pendulum and escapement last
year, they had done 50 million cycles. The valves were still working, but I
swopped them with two of the performance valves which don't have such a hard
life.
The worst maintenance problem to date was the clock becoming unpredictable in
chiming and sometimes not starting up in the morning. It took months and many
visits to find the problem was just a loose collar on the hour hand which caused
the hour hand sensor to fail intermittently.
METALS
AND PAINT
I’ve never liked paint. Probably
it’s because the first job I was given when starting at Magnadove, (the industrial
modelmakers I worked for after leaving college) was to paint their sign board. I
spent two weeks painting and sanding the background white colour, every time
being told to start again – when I started I’d no idea it was possible to
get a hand painted surface completely flat and shiny like a sprayed one…and by
the time I’d finished, it was really flat and shiny, but I never wanted to
paint anything ever again.
But I also dislike paint because it looks great when
its new, but then just gradually looks worse and worse. To me, paint is usually
a bad option when there are so many surfaces which improve with age – wood,
most exposed metal and even some plastics. Surfaces which wear gracefully, like
the metal on my southwold pier clock on are
always more practical and more appealing than those which deteriorate
ungracefully.
So I decided to do without paint on this
clock. The alternatives – anodising and electroplating, both involved
chemistry, and I enjoy messing about with chemicals.
Particularly industrial chemistry which avoids the disappointment of so
much school chemistry! Industrial chemistry is chemistry that has been proved to
work. It still involves a lot of trial and error, but the results are never
unobtainable. Industrial processes never catch on if they aren’t reliable and
easily reproducible.
Finding out about
specialist techniques like anodising and electroplating would have been tricky
in the past. The boss of my local electroplating company is certainly not the
type to encourage DIY forays into his territory. But this is where the internet
is so fabulous. For every speciality, however obscure, there is an enthusiastic
expert. I bought an anodising kit from a man in Wisconsin, a gold plating kit
from a man in Bath (England) and sent ‘Mr Titanium’ from New Mexico a
donation for his site, as it described the process of anodising titanium so
clearly. Experts like this assume
their customers are enthusiastic amateurs like me. The kits were great fun to
try, and the experts all responded enthusiastically whenever I had problems. The
processes I used also shared a surprising amount. The electroplating power
supply was also perfect for anodising the aluminium. The giant vat of sulphuric
acid for anodising the aluminium was also perfect for pickling the copper prior
to electroplating. Chemistry is such a great subject, its baffling to me that it
is possible to make it quite so dull at school.

Prototype anodised titanium wing.
No dyes, just painting with electricity
I hadn’t imagined the birds ending up
so bright and intensely coloured but the processes were so successful they just
seemed to make everything bright. Fortunately I’d just been to zoo on a really
dark winter’s day. Everything looked grey, except for the parrots. Their
colours looked even brighter in comparison with everything around them. So
bright seemed right.
ZOOS
I’ve wanted to
make something for a zoo for a while. I really enjoy
looking at animals, they are astonishing to see in the flesh, so different from
any photo or nature film. On one trip to London Zoo as a child, a tiger pissed
on my cousin Nicola – the volume and force was amazing, like a fire hose, and
she smelt of tiger all day. Nothing on TV can compete with experiences like
this. However, I was increasingly told that zoos were cruel places and that
animals shouldn’t be kept in cages. I still sometimes feel this when I see an
animal restlessly pacing. I don’t like London Zoo’s new gorilla enclosure
because the gorillas still look so sad, though that maybe me anthropomorphising
their normal expression. But as I’ve read more about zoos, I now feel the anti
zoo position is narrow minded. The books and papers use exactly the same
phrases, like some sort of party political line. Nowhere does it really address
the fact that we are ‘naked apes’, members of the animal kingdom, and that
mutual curiosity and interaction are ‘natural’, even if unequal.
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The tiger is actually behind thick glass
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Zoos have greatly improved since my
childhood. Cages have largely disappeared, replaced by more subtle barriers like
moats and electric fences. I’m not sure this makes any difference to the
animals, but it certainly does help visitors feel less guilty. Zoos have got
better at selecting species that thrive in captivity. I spent a day drawing a
bunch of squirrel monkeys a couple of years ago. They have such a busy social
life, with parents, grandparents, children, delinquent teenagers, their life
appears to be a manic soap opera, certainly not lacking in stimulus. Then the
keepers now often talk to the public. It’s really interesting finding out
about the individual animals from the person who looks after them.
Watching the penguin feeding time at London zoo was hysterical because
several penguins were more interested in cuddling up to the keeper than grabbing
the fish. She explained this was because they had been hand-reared, and she then
revealed why the penguins had been moved out of Lubetkin’s 1930s grade one
listed concrete enclosure to an ordinary looking pond. The poor birds had been
developing arthritis from walking on concrete all day. (I’m not sure any
architecture so completely unfit for purpose be grade one listed but this is a
digression.)
Zoos also now stress their importance in
conservation. The number of animal species in danger is certainly scary. Not
everyone believes zoos are any help – they say the gene pool in zoos can never
be large enough for a species to survive exclusively in zoos. But even if this
is true, zoos now champion their role in education, showing us wonderful and
extraordinary animals to encourage us to care about their survival in the wild.
Sometimes this comes across as too worthy for my taste, but the older I get, the
animals
themselves just seem more and more astonishing and worth preserving.
The disapproval of UK zoos in the last
few decades may have been a great asset. They have been starved of cash and so
have avoided the numbing bureauocracy of worthy institutions like the London
Science Museum. Zoos, like seaside piers, have miraculously managed to avoid
becoming part of ‘culture’. People of any age or background go to them with
no pretentions, zoos are just instinctively enjoyable.
A painter I met recently described his
problem with culture, or more precisely cultural institutions. He enjoyed
working in unlikely places, observing and drawing everything happening around
him (which I entirely sympathise with). He said that seeing his finished
paintings in an art gallery always felt disappointing. His rich experiences lost
their power when transported into the tasteful white environment. Maybe culture
has been captured by bureaucrats so its now all presented in standard formats.
Perhaps the root of the problem is that there’s so much ‘culture’ now that
most of what’s in art galleries just isn’t very good. Then culture can also
be a form of snobbishness. Anyway, whatever the reason, personally I just feel
happier working in places like piers, hospitals and zoos.

19th century travelling menagerie
Zoos are far more ancient
than museums or art galleries. The Pharos had collections of exotic animals.
London Zoo started as the king’s collection of animals, on public display at
the Tower of London. In the 18th and 19th centuries zoos
were often part of ‘pleasure gardens’ and travelling menageries often
featured at street fairs. The animals were badly treated so things had to
change, but today zoo animals are well treated, and I suspect the popular
delight in watching animals may be returning. Particularly because more and more
stuff is digital and virtual, experiencing real stuff is becoming more and more
special. My clock was commissioned because it fitted the zoo’s education
aspirations, but I also hope it also celebrates a return to zoo’s showmanship
and sense of fun that was part of the 18th century pleasure gardens.
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