SAW, an instrument which serves to cut into pieces several solid matters, as wood, stone, ivory, &c. The best saws are of tempered steel ground bright and smooth: those of iron are only hammer-hardened: hence, the first, besides their being stiffer, are likewise found smoother than the last.
They are known to be well hammered by the stiff bending of the blade; and to be well and evenly ground, by their bending equally in a bow. The edge in which are the teeth is always thicker than the back, because the back is to follow the edge.
The teeth are cut and sharpened with a triangular file, the blade of the saw being first fixed in a whetting block. After they have been filed the teeth are set, that is, turned out of the right line, that they may make the fissure the wider, that the back may follow the better. The teeth are always set ranker for coarse cheap stuff than for hard and fine, because the ranker the teeth are set the more stuff is lost in the kerf.
The saws by which marble and other stones are cut have no teeth: these are generally very large, and are stretched out and held even by a frame. The workmen who make the greatest use of the saw, are the sawyers, carpenters, joiners, cabinet-makers, ebonists, stone-cutters, carvers, sculptors, &c. The lapidaries too have their saw, as well as the workers in mosaic; but these bear little resemblance to the common saw.
But of all mechanics, none have so many saws as the joiners; the chief are as follows: the pit saw, which is a large two-handed saw, used to saw timber in pits; this is chiefly used by the sawyers. The whip-saw, which is also two-handed, used in sawing such large pieces of stuff as the hand-saw will not easily reach.
The hand-saw, which is made for a single man’s use, of which there are various kinds; as the bow or frame saw, which is furnished with cheeks: by the twisted cords which pass from the upper parts of these cheeks, and the tongue in the middle of them, the upper ends are drawn closer together, and the lower set further apart.
The tenon-saw, which being very thin, has a back to keep it from bending. The compass-saw, which is very small, and its teeth usually not set: its use is to cut a round, or any other compass-kerf: hence the edge is made broad and the back thin, that it may have a compass to turn in.
The surgeons also use a saw to cut off bones; this should be very small and light, in order to be managed with the greater ease and freedom, the blade exceedingly fine, and the teeth exquisitely sharpened, to make its way more gently, and yet with great expedition, in cutting off legs, arms &c.
Saws are now generally used by butchers in separating the bones of the meat; the divisions by the saw are neater than those by the chopper, and there is a certain saving, as the chopper splinters bones the parts of which cannot be included in the weight.
The British Encyclopedia, or, Dictionary of Arts and Sciences – 1809