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Sawmills In The United States
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 of simple operation. 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 follow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cutting Wood With A Portable Sawmill
Cutting is the separation or opening of a physical object, into two or more portions, through the application of an acutely directed force. Implements commonly used for cutting are the knife and saw, or in medicine and science the scalpel and microtome. However, any sufficiently sharp object is capable of cutting if it has a hardness sufficiently larger than the object being cut, and if it is applied with sufficient force. Even liquids can be used to cut things when applied with sufficient force (see water jet cutter). Cutting is a compressive and shearing phenomenon, and occurs only when the total stress generated by the cutting implement exceeds the ultimate strength of the material of the object being cut. The simplest applicable equation is: \text = or \tau=\frac The stress generated by a cutting implement is directly proportional to the force with which it is applied, and inversely proportional to the area of contact. Hence, the smaller the area (i.e., the sharpe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
