A sawmill is a facility where logs are cut into boards. Logging is the process in which Trees are cut down for Forest management and Timber. Lumber or timber is Wood in any of its stages from felling through readiness for use as structural Material for Construction, or
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Sawmill process
A sawmill's basic operation is much like those of 100 years ago; a log enters on one end and dimensional lumber exits on the other end. Lumber or timber is Wood in any of its stages from felling through readiness for use as structural Material for Construction, or
- Logging fells (falls) the trees, and log bucking cuts them to length. Logging is the process in which Trees are cut down for Forest management and Timber. Bucking is the process of cutting a felled and delimbed tree into logs
- Logs are taken by truck, rail or river to the sawmill.
- Logs are scaled either on the way to the mill or upon arrival at the mill. The log scaler is an occupation in the timber industry The Log Scaler measures the cut trees to determine the scale (volume of the wood to be used for Manufacturing.
- Decking is the process for sorting the logs by species, size and end use (lumber, plywood, chips). Plywood is a type of Engineered board made from thin sheets of Wood, called plies or veneers
- Debarking removes bark from the logs.
- The head saw, head rig or primary saw, breaks the log into cants (unfinished planks) with a smooth edge. A head saw, gang saw or head rig is the saw that makes the initial cuts in a log at a Sawmill, turning a log into cants or planks of wood
- Edging will take the cant and trim off all irregular edges leaving four-sided lumber. A lumber edger is a saw used to straighten and smooth rough Lumber or bowed stock by making a cut along the sides of the boards Lumber or timber is Wood in any of its stages from felling through readiness for use as structural Material for Construction, or
- 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. Kilns are thermally insulated chambers or Ovens in which controlled temperature regimes are produced
- Planing smooths the surface of the lumber leaving a uniform width and thickness.
- Shipping transports the finished lumber to market. [1]
History
The earliest known reference to a working sawmill comes from a Roman poet, Ausonius who wrote an epic poem about the river Moselle in Germany in the 4th century AD. This article is about the Roman poet Ausonius For John Ausonius the Swedish murderer see John Ausonius. Moselle is a ''département'' in the east of France named after the Moselle River. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. At one point in the poem he describes the shrieking sound of a watermill cutting marble. It is likely that watermills of all kinds were well used in the Roman period from references given by Vitruvius in 25 BC and Pliny the Elder in 77 AD. This article is about a type of structure For other locational uses see Milldam. Marcus Vitruvius Pollio (born c 80–70 BC died after c 15 BC was a Roman Writer, Architect and Engineer (possibly praefectus fabrum Gaius or Caius Plinius Secundus, ( AD 23 – August 25, AD 79 better known as Pliny the Elder, was an ancient Author
Sawmills were widespread in the medieval period, as one was sketched by Villard de Honnecourt in c. Villard de Honnecourt lived in 13th century France and may have been an itinerant master-builder of Picardy in northern France. 1250. [2] They are claimed to have been introduced to Madeira following its discovery in c. History See also History of Madeira Pre-Portuguese times Pliny mentions certain Purple Islands the position of which with reference to the 1420 and spread widely in Europe in the 16th century. [3]
The sawmill was also described by the Dutchman Cornelis Corneliszoon (1550-1607) by applying a pitman arm onto a wind mill, which converted a turning motion into an up-an-down motion. Cornelis Corneliszoon (c 1550 - c 1600 was the inventor of the Sawmill. The Pitman arm is a Steering component in an Automobile or Truck. Corneliszoon patented the sawmill on December 15, 1593 and the pitman on December 6, 1597. Events 533 - Byzantine general Belisarius defeats the Vandals, commanded by King Gelimer, at the Battle of Events 1060 - Béla I of Hungary is crowned king of Hungary 1240 - Mongol invasion of Rus: Kiev He built the first sawmill there in 1594.
Prior to the invention of the sawmill, boards were rived 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. A saw pit or sawpit is a pit over which lumber is positioned to be sawed with a long two-handled saw by two men one standing above the timber and the other below Sawing was slow, and required strong and enduring 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. A water wheel is a means of extracting power from the flow (or fall of water otherwise known as Hydropower. 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 (thus introducing a term used in many mechanical applications). In a reciprocating Piston engine, the connecting rod or conrod connects the Piston to the crank or Crankshaft. A pitman is similar to a crankshaft, but in reverse; a crankshaft converts back-and-forth motion to circular motion.
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 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 Baltic states (Balti riigid Baltijas valstis Baltijos valstybės or Baltic countries are three countries in Northern Europe, all members of the Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page 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. The United States of America —commonly referred to as the The Commonwealth of Virginia ( is an American state Hamburg (English, German: ˈhambʊɐk local pronunciation Low German / Low Saxon: Hamborg) is the second-largest city in Germany Later the metal parts were obtained from the Netherlands,[4] where the technology was far ahead of that in England, where the sawmill remained largely unknown until the late 18th century. The Netherlands ( Dutch:, ˈnedərlɑnt is the European part of the Kingdom of the Netherlands, which consists of the Netherlands the Netherlands England is a Country which is part of the United Kingdom. Its inhabitants account for more than 83% of the total UK population whilst its mainland The 18th century lasted from 1701 to 1800 in the Gregorian calendar, in accordance with the Anno Domini / Common Era numbering system The arrival of a sawmill was a large and stimulative step in the growth of a frontier community.
Early mills were taken to the forest, where a temporary shelter was built, and the logs were skidded to the nearby mill by horse or ox teams, often when there was some snow to provide lubrication. As mills grew larger, they were usually established in more permanent facilities on a river, and the logs were floated down to them by log drivers. Log driving is a means of log transport which makes use of a river's current by letting the current move floating Tree trunks downstream to Sawmills It was
The next improvement was the use of circular saw blades, and soon thereafter, the use of gangsaws, which added additional blades so that a log would be reduced to boards in one quick step. Circular saw blades were extremely expensive and highly subject to damage by overheating or dirty logs. A new kind of technician arose, the sawfiler. A sawfiler is a person who maintains and repairs saws in a saw mill Sawfilers were highly skilled in metalworking. Their main job was to set and sharpen teeth. The craft also involved learning how to hammer a saw, whereby a saw is deformed with a hammer and anvil to counteract the forces of heat and cutting. The circular saw was a later introduction, perhaps invented in England in the late 18th century, but perhaps in 17th century Holland, Netherlands. The 18th century lasted from 1701 to 1800 in the Gregorian calendar, in accordance with the Anno Domini / Common Era numbering system As a means of recording the passage of Time, the 17th Century was that Century which lasted from 1601 - 1700 in the Gregorian calendar The Netherlands ( Dutch:, ˈnedərlɑnt is the European part of the Kingdom of the Netherlands, which consists of the Netherlands the Netherlands Modern circular saw blades have replaceable teeth, but still need to be hammered. The circular saw is a Metal disc or Blade with Saw Teeth on the edge as well as the Machine that causes the disk to [5]
The introduction of steam power in the 19th century created many new possibilities for mills. A steam engine is a Heat engine that performs Mechanical work using Steam as its Working fluid. The 19th century of the Common Era began on January 1, 1801 and ended on December 31, 1900, according to the Gregorian calendar They could be built away from water and could be far more mechanized. Scrap lumber from the mill provided a ready fuel source for firing the boiler. Efficiency was increased, but the capital cost of a new mill increased dramatically as well.
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 as far as the edge of the Appalachian Mountains in North Carolina. Georgetown is the third oldest city in the US state of South Carolina and the County seat of Georgetown County. The Pee Dee River, also known as the Great Pee Dee River, is a River in North Carolina and South Carolina. The Appalachian Mountains ( often called the Appalachians, are a vast system of mountains in eastern North America. North Carolina ( is a state located on the Atlantic Seaboard in the southeastern United States
A restoration project for Sturgeon's Mill in Northern California is underway, restoring one of the last steam-powered lumber mills still using its original equipment.
Current trends
In the twentieth century the introduction of electricity and high technology furthered this process, and now most sawmills are massive and extremely expensive facilities in which almost every aspect of the work is computerized. A computer is a Machine that manipulates data according to a list of instructions. Today a mill can make many hundreds of thousands of boards per day.
Small gasoline-powered sawmills run by local entrepreneurs served many communities in the early twentieth century, and specialty markets still today.
The latest trend is the small portable sawmill for personal or semi professional use. Portable sawmills became popular in the United States starting in the 1970s when the 1973 energy crisis and the Back to the land movement had led to renewed Many different models have emerged with different designs and functions. They are especially suitable for producing limited volumes of boards, or specialty milling such as oversized timber.
Technology has changed sawmill operations significantly in recent years, emphasizing increasing profits through waste minimization and increased energy efficiency as well as improving operator safety. The once-ubiquitous rusty, steel conical sawdust burners have for the most part vanished, as the sawdust and other mill waste is now processed into particleboard and related products, or used to heat wood-drying kilns. A cone is a three-dimensional Geometric shape that tapers smoothly from a flat round base to a point called the apex or vertex A wood waste burner known as a teepee burner or wigwam burner in the United States and a beehive burner in Canada, is a free-standing conical Particle board, or particleboard, (called "chipboard" in some countries is an Engineered wood product manufactured from Wood particles such Kilns are thermally insulated chambers or Ovens in which controlled temperature regimes are produced Everything is used. While the bark may be ground for landscapine barkdust, it may also be burned for heat. Sawdust may make particle board or be pressed into wood pellets for pellet stoves. The larger pieces of wood that won't make lumber are chipped into wood chips and provide a major source of supply for paper mills. Wood by products of the mills will also make Oriented strand board paneling for building construction, a cheaper alternative to plywood for paneling. Oriented strand board, or OSB, or waferboard or Sterling board (UK is an Engineered wood product formed by layering strands (flakes of
Additional Images
 Inside a modern sawmill equipped with laser-guided technology |
 Wood traveling on sawmill machinery |
 Sawdust waste from the mill |
 Wood from Victorian mountain ash, Swifts Creek |
See also
References
- ^ Lumber Manufacturing. Swifts Creek is a rural community located between Omeo and Ensay on the Great Alpine Road in East Gippsland, Victoria, Australia A band saw uses a blade consisting of a band of toothed metal and may be powered by wind water steam electrical motor or animal power The circular saw is a Metal disc or Blade with Saw Teeth on the edge as well as the Machine that causes the disk to Portable sawmills became popular in the United States starting in the 1970s when the 1973 energy crisis and the Back to the land movement had led to renewed A sawfiler is a person who maintains and repairs saws in a saw mill Bucking is the process of cutting a felled and delimbed tree into logs Logging is the process in which Trees are cut down for Forest management and Timber. A saw pit or sawpit is a pit over which lumber is positioned to be sawed with a long two-handled saw by two men one standing above the timber and the other below Lumber Basics. Western Wood Products Association (2002). Retrieved on 2008-02-12. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 1429 - English Forces under Sir John Fastolf defend a supply convoy carrying rations to the army besieging Orleans from attack by the
- ^ C. Singer et at. , History of Technology II (Oxford 1956), 643-4.
- ^ Charles E. Peterson, 'Sawdust Trail: Annals of Sawmilling and the Lumber Trade' Bulletin of the Association for Preservation Technology Vol. 5, No. 2. (1973), pp. 84-5.
- ^ Peterson, 94-5.
- ^ Norman Ball, 'Circular Saws and the History of Technology' Bulletin of the Association for Preservation Technology 7(3) (1975), pp. 79-89.
External links
- Steam powered saw mills
- The basics of sawmill (German)
- Nineteenth century sawmill demonstration
- Database of worldwide sawmills
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