Жылқыштарды кесу орны Ағаш кесетін завод

Facility where logs are cut into lumber

A sawmill (saw mill, saw mill) or lumber mill is a facility where logs are cut into lumber. Modern sawmills use a motorized saw to cut logs lengthwise to make long pieces, and crosswise to length depending on standard or custom sizes (dimensional lumber). The "portable" sawmill is simple to operate. The log lies flat on a steel bed, and the motorized saw cuts the log horizontally along the length of the bed, by the operator manually pushing the saw. The most basic kind of sawmill consists of a chainsaw and a customized jig ("Alaskan sawmill"), with similar horizontal operation. Before the invention of the sawmill, boards were made in various manual ways, either rived (split) and planed, hewn, or more often hand sawn by two men with a whipsaw, one above and another in a saw pit below. The earliest known mechanical mill is the Hierapolis sawmill, a Roman water powered stone mill at Hierapolis, Asia Minor dating back to the 3rd century AD. Other water powered mills followed and by the 11th century they were widespread in Spain and North Africa, the Middle East and Central Asia, and in the next few centuries, spread across Europe. The circular motion of the wheel was converted to a reciprocating motion at the saw blade. Generally, only the saw was powered, and the logs had to be loaded and moved by hand. An early improvement was the development of a movable carriage, also water powered, to move the log steadily through the saw blade. By the time of the Industrial Revolution in the 18th century, the circular saw blade had been invented, and with the development of steam power in the 19th century, a much greater degree of mechanisation was possible. Scrap lumber from the mill provided a source of fuel for firing the boiler. The arrival of railroads meant that logs could be transported to mills rather than mills being built beside navigable waterways. By 1900, the largest sawmill in the world was operated by the Atlantic Coast Lumber Company in Georgetown, South Carolina, using logs floated down the Pee Dee River from the Appalachian Mountains. In the 20th century the introduction of electricity and high technology furthered this process, and now most sawmills are massive and expensive facilities in which most aspects of the work are computerized. Besides the sawn timber, use is made of all the by products including sawdust, bark, woodchips, and wood pellets, creating a diverse offering of forest products.

A sawmill's basic operation is much like those of hundreds of years ago: a log enters on one end and dimensional lumber exits on the other end. After trees are selected for harvest, the next step in logging is felling the trees, and bucking them to length. Branches are cut off the trunk. This is known as limbing. Logs are taken by logging truck, rail or a log drive to the sawmill. Logs are scaled either on the way to the mill or upon arrival at the mill. Debarking removes bark from the logs. Decking is the process for sorting the logs by species, size and end use (lumber, plywood, chips). A sawyer uses a head saw (also called head rig or primary saw) to break the log into cants (unfinished logs to be further processed) and flitches (unfinished planks). Depending upon the species and quality of the log, the cants will either be further broken down by a resaw or a gang edger into multiple flitches and/or boards. Edging will take the flitch and trim off all irregular edges leaving four sided lumber. Trimming squares the ends at typical lumber lengths. Drying removes naturally occurring moisture from the lumber. This can be done with kilns or air dried. Planing smooths the surface of the lumber leaving a uniform width and thickness. Shipping transports the finished lumber to market.

[[File:Römische Sägemühle. svg|thumb|Scheme of the water driven sawmill at Hierapolis, Asia Minor. The 3rd century mill incorporated a crank and connecting rod mechanism. Water powered stone sawmills working with cranks and connecting rods, but without gear train, are archaeologically attested for the 6th century at the Byzantine cities Gerasa (in Asia Minor) and Ephesus (in Syria). The earliest literary reference to a working sawmill comes from a Roman poet, Ausonius, who wrote a topographical poem about the river Moselle in Germany in the late 4th century AD. At one point in the poem he describes the shrieking sound of a watermill cutting marble. Marble sawmills also seem to be indicated by the Christian saint Gregory of Nyssa from Anatolia around 370–390 AD, demonstrating a diversified use of water power in many parts of the Roman Empire. Sawmills later became widespread in medieval Europe, as one was sketched by Villard de Honnecourt in c. 1225–1235. They are claimed to have been introduced to Madeira following its discovery in c. 1420 and spread widely in Europe in the 16th century. Prior to the invention of the sawmill, boards were rived (split) and planed, or more often sawn by two men with a whipsaw, using saddleblocks to hold the log, and a saw pit for the pitman who worked below. Sawing was slow, and required strong and hearty men. The topsawer had to be the stronger of the two because the saw was pulled in turn by each man, and the lower had the advantage of gravity. The topsawyer also had to guide the saw so that the board was of even thickness. This was often done by following a chalkline. Early sawmills simply adapted the whipsaw to mechanical power, generally driven by a water wheel to speed up the process. The circular motion of the wheel was changed to back and forth motion of the saw blade by a connecting rod known as a pitman arm (thus introducing a term used in many mechanical applications). Generally, only the saw was powered, and the logs had to be loaded and moved by hand. An early improvement was the development of a movable carriage, also water powered, to move the log steadily through the saw blade. A type of sawmill without a crank is known from Germany called "knock and drop" or simply "drop" mills. In these drop sawmills, the frame carrying the saw blade is knocked upwards by cams as the shaft turns. These cams are let into the shaft on which the waterwheel sits. When the frame carrying the saw blade is in the topmost position it drops by its own weight, making a loud knocking noise, and in so doing it cuts the trunk. A small mill such as this would be the center of many rural communities in wood exporting regions such as the Baltic countries and Canada. The output of such mills would be quite low, perhaps only 500 boards per day. They would also generally only operate during the winter, the peak logging season. In the United States, the sawmill was introduced soon after the colonisation of Virginia by recruiting skilled men from Hamburg. Later the metal parts were obtained from the Netherlands, His wind powered sawmill used a crankshaft to convert a windmill's circular motion into a back and forward motion powering the saw, and was granted a patent for the technique.