BAND SAWS, wood saws consisting of a continuous band of steel carrying saw teeth on either or both edges and mounted on two wheels arranged above and below or at either side of a work-table. Power is applied to one of the wheels, moving the band at a high rate of speed, the other wheel being so mounted as to permit it to be moved away from the power wheel to insure tightness of the band during the cut. One of the first applications of the band saw principle is recorded in the British patent office, in connection with a patent issued to William Newberry in 1808. The development at first was slow due to the greater cost of manufacture in comparison to the circular saw. As the need of conserving lumber became more apparent the great saving, as much as 6o% in favour of the band saw, hastened its develop ment and adoption.
There are several forms of the band saw. The scroll saw, a simpler form, has an adjustable table for sawing bevels, and has the wheel bearings mounted on a column. Blades as narrow as -kin. are used and it is possible to turn the work as it is being cut so that intricate designs of small radius may be obtained. The band rip saw is equipped with a wider blade suitable for ripping any length of stock at high speed, and with feed rolls which grip the stock above and below. A variation of this type has an end less feeding chain in the table and with feed rolls above insures ripping on a straight line. The band re-saw has only a very narrow worktable, and thick planks are fed through to be cut into thinner boards. A variation of the re-saw consists of two blades offset so as to cut a plank into three boards at one passage. The largest form is the band mill saw which is used in the first cutting of timber into planks. The size of the wheels are often as much as i of t. in diameter and the blades as wide as 14 inches. The car riage upon which the log is mounted moves the timber sideways after each cut, an amount equal to the thickness of boards being cut, and draws it away from the band after the cut to prevent the band being pushed off the wheel. Some mills are made with teeth on both edges of the blade and a cut is made on both the forward and return movement.