Decking is the process for sorting the logs by species, size and end use (lumber, plywood, chips).
Logs are scaled either on the way to the mill or upon arrival at the mill. Logs are taken by logging truck, rail or a log drive to the sawmill. After trees are selected for harvest, the next step in logging is felling the trees, and bucking them to length. 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.Ī 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. 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. By 1900, the largest sawmill in the world was operated by the Atlantic Lumber Company in Georgetown, South Carolina, using logs floated down the Pee Dee River from the Appalachian Mountains. The arrival of railroads meant that logs could be transported to mills rather than mills being built beside navigable waterways. Scrap lumber from the mill provided a source of fuel for firing the boiler. An early improvement was the development of a movable carriage, also water powered, to move the log steadily through the saw blade.īy 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. Generally, only the saw was powered, and the logs had to be loaded and moved by hand. The circular motion of the wheel was converted to a reciprocating motion at the saw blade. 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 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. #SAWMILL CROSSING MANUAL#
The most basic kind of sawmill consists of a chainsaw and a customized jig ("Alaskan sawmill"), with similar horizontal operation.īefore 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 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 "portable" sawmill is simple to operate. 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). Early 20th-century sawmill, maintained at Jerome, Arizona.Ī sawmill ( saw mill, saw-mill) or lumber mill is a facility where logs are cut into lumber.
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