Work update
June '01
Matrimandir's glass inner skin
For many months research has been
ongoing in Matrimandir's "inner skin workshop" on
site, to identify and solve the problems of providing a glass
cladding which will line the sphere of the Matrimandir from the
inside. The manufacture of the big peach-coloured triangular
panels - 800 of them, covering 3,000 square metres in total -
will be needed to complete the work.
In order to give our viewers some idea of what is involved, we
post here a progress report, even though it is not really a
regular 'work update'.
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Experimentation in the glass workshop |
Large triangular glass panels
A large kiln, whose internal dimensions
are 4 x 3 mtr x 2 mtr high, was built in 1999 for the purpose of
fusing colour onto the surface of 8 mm thick float-glass panels.
After being laminated to a second sheet of clear glass for
reasons of safety, these panels will be used for the inner skin
of Matrimandir. Some 800 panels are required, each triangular in
shape and roughly measuring 3 mtr at the base and 2.4 mtr high.
(Even though the height of each triangle is the same, the shapes
differ considerably.)
4 x 3.6 mtr silk-screen frame
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The 4 x 3.6 mtr silk-screen frame (largest in the world?) |
The colour being used is an oil emulsion
containing a mixture of orange and yellow cadmium and other
oxides. The emulsion is passed through a homogeniser to produce
a very fine paste suitable for silk-screen application.
Before the method of using a silk-screen was selected, other
methods of applying the colour were tried, such as spraying.
This tended, however, to give a spotty surface and excess
evaporation, so was discontinued. Once small-scale silk-screen
tests proved successful, a full-scale approach was adopted. For
this purpose a very large silk-screen frame measuring 4 x 3.6
mtr was imported from Germany, such a large screen being
unavailable in India.
This silk-screen frame is mounted horizontally just above the
surface of the glass, and a special table with a movable rubber
applicator was built to accommodate it.
Work of great precision
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Moment of precision: as the upper frame is evenly moved over the glass beneath the silkscreen, the paint is squeezed down through the screen onto the glass. |
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After the silkscreen
procedure |
Once the colour has been applied, the glass triangle is placed
on a trolley and wheeled into the oven for fusing. It was found
that the evenness of the layer of pigment was as important as
the firing itself in yielding the precise colour.
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The glass panel on the way to the kjiln |
Another particular problem has been how to clean the silk-screen
after use. Given the size of the frame, the initial cleaning
method involved standing in front of the vertically positioned
screen and using turpentine or NC thinner to remove the residue
of orange paste. Subsequently, we have found a simpler method
which allows for the frame to remain in a vertical position
while a long-handled brush is used to clean the surface using
kerosene. The kerosene can be recycled since it collects in a
catchment under the frame; once the residue settles and
separates, it can be siphoned off and used again.
Lamination
Before the coloured glass produced in the
oven can be used, it has to be laminated with a second sheet of
plain glass of the same size and shape in order to produce a
safety glass. This is necessary because the spherical shape of
Matrimandir's shell means that large sections of the inner glass
surface will be suspended above the heads of those moving around
in the building's interior. Thus safety glass is absolutely
necessary. The two-glass sheets will be laminated using a resin
made specially for such purposes.
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The mounting of one of the panels on the inner surface of
Matrimandir's spaceframe |
White glass from Germany
During the first half of this year,
several preliminary samples of full-scale panels have been made
and mounted inside the Matrimandir. We have been focusing on the
thorough testing of the firing sequence, and details of fixation
of the panels to the concrete beams which make up the
space-frame of the Matrimandir. The panels will be mounted on
aluminium profiles imported from Germany.
As for the glass, efforts to identify the
best supplier of the white glass needed to achieve the most
satisfactory results in terms of the colour have directed us to
Germany once again. They may soon be forthcoming.
Next row of discs
To come back to the structure itself: a
team is busy finishing the set of stainless steel horizontal
catwalks that encircle the Matrimandir at the equator. These
ladders will provide for access to the outside of the building
for cleaning and maintenance for years to come. The platform on
which the team is perched has been in its present position for
about six months. Everyone is keen to finish work at this level
and move downward: everyone wants to see the rows of discs
appear beneath the equator. There is no shortage of discs, 85 %
of the discs is ready, and from this, 50 % is already fixed,
another 35 % is hanging in the stock. (If we can keep up the
present pace of production, all discs may have been produced by
November this year.)
June 15, 01
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