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Portable SawmillPortable 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 interest in small woodlots and in self-sufficiency. Prior to the advent of the portable 'mill, small-scale sawmills were generally cobbled-together affairs constructed and operated by (almost always) two men with a penchant for tinkering. This was, and remains, a traditional occupation for Amish men; unlike most mechanical systems, small sawmills typically do not use electricity. The portable 'mills represented the first effort at careful engineering and design. Unlike traditional mills, they used a resaw blade of the type used on a band saw rather than a circular blade, which reduced weight and cost, and reduced the size and weight of the bearings and support blocks. It also allowed for a different design where the head, consisting of the blade and a power source, moves back and forth while the log being cut remains stationary. This is in contrast to traditional mills where the log moves on a trolley while the blade remains fixed. Portable mills can be trailered and set up on site, next to the trees being cut, though in practice this is sufficiently time-consuming that it is rarely done. There is a good degree of shimming and alignment to get the rails set up straight, and this takes time. Some business transport their mill to harvest urban timber where moving the logs would be impractical. Larger mills have recently come on the market which are portable only in sections. These are faster and can handle larger logs. Uses The portable mills can cut lumber with speed and accuracy, though the subsequent steps of planing and drying must still be performed to produce finished lumber. Commodity lumber in standard sizes can be made this way. Occasionally, this is done. The more common use, however, is in the production of specialty timber products not readily available through lumber yards. Portable mills are particularly effective for truing up logs for use in log construction, replacing the traditional use of a drawknife, which is inordinately time-consuming. They are also used for low-volume production of specialty hardwoods used in furniture, and can be used to produce the large timbers used in post-and-beam framing techniques. Related machinery Jigs are commercially available that allow a chainsaw equipped with a ripping chain to be used like a sawmill.
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