Manufacturing
Processes and Grain Direction
Paper fibers have certain characteristics that depend upon the
nature of the composition of the fiber and the way in which
it is milled. As climate changes, the fibers can expand and
contract considerably in their thickness, but, in terms of length,
they remain virtually unaltered.
The way that paper
fibers are laid down in sheets during manufacturing determines
the grain direction.
Machine-Manufactured
Paper
Paper produced by machinery—vat machines or long web machines—has
a pronounced grain direction because the fibers align themselves
parallel to the direction of movement on the machine.
Hand-Made Paper
The highly diluted pulp of a hand-made paper is evenly spread
over a web through manual shaking which causes the fibers to
follow a random orientation. For this reason, there is no discernible
grain direction in hand-made paper, and the effects of expansion
and contraction are virtually identical in both directions.
