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dust press tiles

updated fri 5 mar 04

 

Stephani Stephenson on thu 4 mar 04


In 1840 , in Great Britain , a man named Richard Prosser took out a
patent for a technology which could press buttons from clay dust.
Herbert Minton took a share in the patent and used the technology, a
hand operated flywheel press which compacted clay dust between metal
dies, to press tile.
One skilled person, with an assistant can make about 3000 tile per
day with this type of press. The presses had a reputation for being
dangerous, as they did not have guards, and the flywheels could come
down with such force and velocity it could mash fingers...Each press
was operated by one person only , to avoid a timing mistake which
would lead to injury.. Also a handle attached to flywheel could bean
anyone who moved the wrong way at the wrong time.
I have read that optimum moisture content of clay dust for pressing
is 10%-20%, and humidity and moisture regulation are needed to make
consistent tiles.
One way the dust body is prepared is by pumping clay slip into a
filter press, where clay cakes are produced which are then dried and
crushed. Another way is to spray slip into a cylinder shaped drier
where is hit with hot air and dried instantaneously. In this method
the particles are dried separately and so do not have to be crushed,
but instead are sent down a conveyor belt, moisture content held
constant to the presses.
At the press, the cavity part of the die is filled with dust and
leveled and then the other part of the die is brought down on it,
often twice....
Though the original flywheel press itself is studio scaled, dust
pressing is done for the most part on a large scale, with multiple
tiles pressed at once and it is largely automated,.....
the flywheel press and Minton tile brought tile making into the
industrial age.
Until that time, the mid eighteen hundreds, tile making was a craft
based or studio based occupation.
Interestingly this invention and change came about at a time in Great
Britain when there was a resurgence of interest in everything Medieval
, i.e. the Gothic revival. Tilemakers were sought after by churches ,
abbeys and cathedrals to find ways to repair and replace some of
their beautiful encaustic tiled floors, originally installed in the
middle ages.
The increase in tile production, due to the introduction of dust
pressing, also led to an increase in availability, and also... demand.
Tile became the rage. I have seen photos of some beautiful tiled
Dairies in Great Britain.
Of course periodically there have been revolts against the
industrialization of it all... the Arts and Crafts era saw many
tilemakers turning to studio and smaller scale tile making, using moist
clay once again, rather than dust pressed clay, and even today, bucking
the trend of large scale tile manufacture are both traditional clay
workers who make tiles or building blocks of clay in countries where
the methods and technology may not have changed in centuries, and the
modern throwbacks who live in countries like the U.S. , and who, like
wheel potters who live here, have rediscovered the craft or studio
traditions in making tile, and who are finding niche markets for it.

. Stephani Stephenson
steph@alchemiestudio.com