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In the construction of a letterpress "form" older methods of
image making involving cast metal, plated molds, and other media have been
replaced with photopolymer relief plates in those instances where
letterpress equipment is still functional There are a few presses still
availing themselves of old type and casts, and using ancient type-making
machines (like linotype) but there are few persons alive today who know
how to operate, much less keep them in functional repair.
The usage of cast metal type was replaced in some instances with
typewriter generated "cold type", by the Varityper, Friden
Justowriter, IBM Selectric Composer and these were replaced in part by
photographic and then electronic platemaking. The development of
photopolymer relief plates began to replace all of the above when
letterpress hit its prime, and is now the most economical platemaking
method available.
As letterpress usage grew, it became obvious that for long runs of the
same copy, duplicate plates would save time and money. Stereotype,
electrotype, rubber and plastic duplicate platemaking thrived, but are no
longer widely used for letterpress work. The more economical and faster to
produce photopolymer plates are extending the life of letterpress printing
to some extent.
Photoengraving, at one time thought to be the last word in platemaking,
is still in use to a limited extent, however photopolymer plates are less
expensive, quicker to make, and supply fewer chemical residues, as a
result the equipment to make photopolymer plates and the plates themselves
provide an undeniable cost saving without jeopardizing the quality of the
finished product. Chemical engraving has taken a back seat to mechanical
and electronic computer driven engraving methods because of environmental
reasons as well as cost and speed. Typesetting is also being done by
computers, and films, where used, are often laser generated.
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