Design Nomenclature / Surface & Material

Grain

Also called wood grain, paper grain, film grain, rolling direction

The directional structure a material carries from how it was made — fibers aligned in wood and paper, silver halide in film, the rolling direction in sheet metal. Because it is directional it has a with and an against, which is why paper tears straight one way and wood planes clean one way and tears out the other.

A sheet of paper seen face-on, its fibers lying predominantly along one axis, with that axis dimensioned beneath as the grain direction. Two tears, deliberately running different ways. One runs parallel to the fibers, parting them rather than breaking them, and holds a line. The other runs across them, has to break every fiber it meets, and wanders from side to side as it goes.

In practice

Grain direction is a spec, not a description. Bind a book across the grain and it will never lie flat, and no amount of pressing fixes it.

Not to be confused with

How this term connects

Abrasive finishingAnisotropyBrushed finishLap jointMortise and tenonNapSheet metalTear-outTextureToothGrain
Related Confused with