Type casting (typography)

[1] Although using matrices was a technique known well before his time, Johannes Gutenberg adapted their use to a conveniently adjustable hand mould, enabling one to easily and accurately cast identical multiple instances of any character.

The ultimate product of manual typecasting were letters, known as sorts for letterpress printing, and the process starts with the installation of a matrix with the impression of a particular glyph into the bottom of the hand mould which is adjusted for the width of the body and locked in preparation for casting.

Molten type metal alloy would be carefully poured into a straight-sided vertical cavity at the top of the mould.

Although the Linotype (1886) and Intertype (1914) approach to mechanical typesetting produced cast slugs that usually represent the complete line instead of individual characters, it still made use of individual bronze matrices stored in a magazine at the top of the machine, dispensed one per keystroke, assembled, sent to the caster where the slug was cast and the matrices re-distributed using a clever V-shaped keying mechanism.

The Ludlow display typecasting system is similar, in that it is also a linecasting process, although all the typesetting operations (matrix assembly and later distribution) are executed manually by a compositor.