A bandsaw (also written band saw) is a power saw with a long, sharp blade consisting of a continuous band of toothed metal stretched between two or more wheels to cut material. They are used principally in woodworking, metalworking, and lumbering, but may cut a variety of materials. Advantages include uniform cutting action as a result of an evenly distributed tooth load, and the ability to cut irregular or curved shapes like a jigsaw. The minimum radius of a curve is determined by the width of the band and its kerf. Most bandsaws have two wheels rotating in the same plane, one of which is powered, although some may have three or four to distribute the load. The blade itself can come in a variety of sizes and tooth pitches (teeth per inch, or TPI), which enables the machine to be highly versatile and able to cut a wide variety of materials including wood, metal and plastic. Almost all bandsaws today are powered by an electric motor. Line shaft versions were once common but are now antiques. History The idea of the bandsaw dates back to at least 1809, when William Newberry received a British patent for the idea, but bandsaws remained impractical largely because of the inability to produce accurate and durable blades using the technology of the day. Constant flexing of the blade over the wheels caused either the material or the joint welding it into a loop to fail. Nearly 40 years passed before Frenchwoman Anne Paulin Crepin devised a welding technique overcoming this hurdle. She applied for a patent in 1846, and soon afterward sold the right to employ it to manufacturer A. Perin & Company of Paris. Combining this method with new steel alloys and advanced tempering techniques allowed Perin to create the first modern bandsaw blade. The first American bandsaw patent was granted to Benjamin Barker of Ellsworth, Maine, in January 1836. The first factory produced and commercially available bandsaw in the U.S. was by a design of Paul Prybil. Power hacksaws (with reciprocating blades) were once common in the metalworking industries, but bandsaws and cold saws have mostly displaced them. Types Residential and light industry Many workshops in residential garages or basements and in light industry contain small or medium-sized bandsaws that can cut wood, metal, or plastic. Often a general-purpose blade is left in place, although blades optimized for wood or metal