The carpentry workshop and wood

Sawn materials are obtained by sawing logs: plate, board, lath, beam, sleeper and others. Sawn material must have two parallel flat faces. A board planed on at least one face is called a planed board. The suitability of wood is found by testing: appearance, hardness, density and resistance to outside effects. A simple test of hardness is to drive a nail into it: an ordinary nail cannot be driven into hard woods such as elm, oak, pear and acacia, but goes easily into soft ones such as willow, poplar and pine. If water leaves a drying log unevenly, cracks, twisting and bending appear; so wood is weighted down and dried with air touching it evenly.