WhenLetter to the Censors arrived at Tate
there were a number of damages and loses. It was not clear at what stage
these had occurred, but it was obvious that this work was highly vulnerable
to damage both whilst on display and in transit. With works which are
this fragile, the risks inherent in transit and display mean that conservation
involves a high level of hands-on treatment; with the conservator on
standby to nurse and repair delicate elements.
Two new packing cases were designed to safely store
this extremely fragile work and to minimise the risk of damage occurring
during transport.
After much discussion it was decided that the architectural model should
be packed on its own in one crate and not be wrapped in tissue. The
risk of the tissue catching and breaking the fragile details was greater
than the protection offered. The model rests on foam blocks made from
a stable closed-cell polyethylene designed to absorb vibration and shocks
during transit. All other constituents are packed in crate two. All
the small elements such as the figures and lanterns are kept in plastic
boxes which are packed in a storage bin.
The electronic equipment and the metal frame with
the fans are removed from equipment space inside the model and packed
separately for transit.
During transit the relative humidity and temperature
conditions inside the crate are monitored by Tinytag data loggers.
Due to the fragility of this object it is unlikely
that the work can be moved without minor damages occurring even in the
newly designed cases. In the following clip the conservator Neil Wressel
discusses the difficulties in safely transporting this work.
Neil Wressell, Conservator
Describes the difficulties of transporting the work
It is part of Tate’s standard practice for the conservation
of video to hold a preservation master in an uncompressed component
video format which can be migrated every 5 to 6 years onto new stock,
and if necessary new formats, to ensure its long term preservation.
In order to create this preservation master, Tate borrowed material
from the artist. In this case the video elements had been compiled by
the artist onto Mini DV but without the soundtrack. It was therefore
necessary to work with the artist to ensure that the preservation master
held by Tate was an accurate record of both the final video and audio.
Although the preservation master material is stored
uncompressed, the exhibition format of the compiled audio and video is
a compressed format called MPEG-2. MPEG-2 is the name of the compression
algorithm which is also used for commercial DVDs. In Letter to the
Censors the MPEG-2 files are played back using a small computer based
MPEG-2 player. The projector used is a DLP projector made by DreamVision.
These devices were chosen because they are small and reliable and would
fit in the restricted space above the foyer.
During the operation of the projector air is circulated
to cool the lamp and warm air is expelled. This caused the temperature
inside the space, above the foyer, to rise. The increased temperature
caused the roof to warp and the joints of the construction to open.
Temperatures above 40°C also affected the electronic equipment causing
it to overheat.
A Tate conservation technician, Karl Bush, carried out
a series of tests in order to explore ways of lowering the temperature
within the roof space which held the equipment. The cooling system which
was developed consisted of seven fans intended for computers. These fans
are designed to run quietly allowing the noise levels to be kept low.
The fans are attached to a freestanding metal frame inside the equipment
space. The roof of the cinema is positioned so that there is a small gap
which allows the movement of air between the cavity and the outside.
Initially, the fans were tested with a mock up of
the ceiling cavity until conservation was sure that they could achieve
temperatures below 40°C. The cooling system allows the work to be displayed
safely, without permanently altering the model. During the display the
temperature and relative humidity (RH) are monitored with a Tinytag
data logger inside the model to check that the system is working effectively.
A temperature sensitive automatic switch, which will cut the power to
the equipment, is currently in development and will be installed the
next time the work is displayed.
Tina Weidner, Conservator,
Describes the design of the cooling system
The factory-made light boxes were
fabricated so that the fluorescent tubes inside the units could not be
changed when they failed. The metal clips, which hold the fluorescent
tubes, were bent and had been soldered to the pins at both ends of the
tubes. Although the published life span of these lamps was approximately
2 and a half years some of the lamps had already failed and needed to
be replaced. The solder was removed and the clips were then replaced allowing
the lamps to be easily changed when necessary.
When the model arrived at Tate it had suffered a number
of breaks and losses. Many of the loose elements were located inside
the model making it necessary to dismantle some of the elements. As
well as dealing with damage, a decision was made to upgrade the wiring
and change the light source for the chandelier.
The chandelier is made of clear
plastic with separate beads and swags. Originally the chandelier was lit
with a single small bulb but there were concerns about how this would
be accessed when it needed to be changed. The artist was consulted and
it was decided that the lighting should be ‘twinkly’. After some experimentation
by Sue Shepherd of the company Neon Circus, thirty-two fibre optic strands
were used as a substitute for the original bulb. An optical fibre is a
thin transparent strand made of glass or plastic which transmits light
along its axis by internally reflecting it. Each fibre can be clipped
at any point, revealing a light beam of the same diameter as the fibre.
These fibre optic strands were threaded through and around the perimeter
of the chandelier. Where necessary, the fibres were tied to the chandelier
with nylon thread, with the intention to position the ends of the fibres
to imitate a three-tier chandelier when lit.
The brass wire, which holds the chandelier in position,
is pushed through the hole in the ceiling together with the fibres and
is tied around a screw next to the hole. The fibres were then connected
to its light source, which is placed in the projection space allowing
for easy access should the lamp fail and need to be replaced.
The chandelier was repaired using Balsa cement, a
cellulose nitrate adhesive, chosen because it enabled the conservator
to reattach the broken parts without applying weight. This was essential
due to the chandelier's fragility.
There are twenty-nine miniature lanterns made from very thin
balsa wood which hang on brass wire brackets attached to the outside
of the model. Several of the brackets had become loose during transit
or were lost and needed to be re-adhered or remade. Of the twenty-nine lanterns,
half had been broken or had missing elements. All the loose pieces were
re-fixed and missing elements were replaced using thin balsa wood
which was stained with water colours to match the originals.
Balustrade, finials, columns, pilasters and
scaffolding
There were numerous areas of loss and damage to the
architectural details of the model. In some cases repairs could be made,
whereas other elements had to be re-carved. These were carefully documented
in the conservation report so it would be clear in the future which
elements were original and which had been remade.
Elements within the censor’s office had become loose.
The silver coins, which represent reels of film, had spilled from the
shelf onto the floor. The old adhesive was removed and the ‘cans’ were
arranged back onto the shelves, loosely following a pattern recorded
in a photograph supplied by the artist. The adhesive used was Paraloid
B72 an ethyl methacrylate copolymer.
The readagraph, which displays the title of the work,
the ‘director’ and the cinema’s opening hours at the front entrance,
was repaired as some of the letters and the wires which are used to
attach it to façade had become loose.
The figures were analysed by
Conservation Science at Tate using FTIR (Fourier Transform
Infrared Spectroscopy) and were found to be made from beeswax and chalk
with a dark green pigment added for colour. This modelling material, similar
to Plasticine, deteriorates with age as the beeswax becomes brittle and
shrinks with oxidation. The figures were modelled using this material
and then coated with a varnish.
The figures which are permanently attached underneath
the arcades and in the foyer are particularly vulnerable, as these can
not be stored or shipped separately. During transport eight figures suffered
broken limbs and/or heads. All of the broken pieces were reattached
with a cynoacrylate adhesive. This proved very efficient in that it
dried fast and did not cause any distortion in the figures.
The conservation team were concerned about the hand-modelled
figures as they were known to be made from an unstable material. The figures
are finely detailed, each one displaying individual character. The permanently
fixed figures are at risk of repeated damage during transport and the
loose figures have proved susceptible to theft. The surface of the figures
remains slightly soft. This makes them vulnerable to damage from handling
and encourages the build up of dust which obscures the details of the
modelling.
The risk of loss to this key part of the work was
significant. The conservation team and curator felt that one way of
preserving the figures would be to make replicas for display enabling
Tate to preserve the original figures in a controlled environment for
future reference. Although this would represent an unconventional approach,
these objects are so vulnerable that such a solution was worth consideration.
In collaboration with the artist, Tate Conservation
explored different options for the preservation of the original figures.
Producing replicas by casting the figures
Remodeling the figures by hand out of a more stable material
Remodeling the figures using 3-dimensional scanning and rapid prototyping
The idea of producing cast replicas was dismissed
as impractical given the fragility of the original figures.
Initial tests were carried out to re-model the figures
by hand using Milliput superfine white – a two part epoxy putty which
is commonly used by plumbers. It quickly became clear that it was going
to be both difficult and time-consuming to replicate the individual
gestures of the figures using Milliput.
The third option explored was 3-dimensional laser
scanning and rapid prototype modelling, a technique that enables exact
replicas to be made.
