PLANE, a perfectly flat surface. In mechanical manipulation, a tool or instru ment for producing a straight even sur face. It consists of it cutter, which is placed in an oblique position in a wooden stock, whose under surface is perfectly straight, the edge of the cutter protruding slightly through the face of the stock. It is principally used for wood, and is laid fiat on the surface, and worked backwards and forwards by the workman, every for ward movement taking off a shaving. PLANING MACHINE. A machine for planing either wood or metal. The wood planing machine is, on account of the immense consumption of timber, one of the most valuable machines in use in the United States, as almost all the plank used is planed by it, and except in joiners' work, it may be said to have almost su perseded the hand plane. The first planing machine ever used was the inven tion of Jeremy Bentham, of England, and was patented in that country towards the close of the last century. It consisted of planes nearly similar to the hand plane, driven hack and forth by machinery, the hoards being held down on a suitable bed by pressure. The next machine was in vented in 1801, by Joseph Bramah, of London, the celebrated mechanician, and inventor of the hydrostatic press ; in this machine the cutters are attached to a re volving disc, the boards being laid par allel to the face of the disc, and moved by suitable means longitudinally, during the time the cutters are passing across their faces. The "Bramah disc," as it is term ed, is in common use in this country at the work day, and for some kinds of work is better than any other arrange ment of cutters.
The best machine for general purposes, particularly for planing flooring boards,: is known as the Woodworth machine. The cutters in this machine are arranged at intervals apart, around a cylinder, or in cylindrical form, the edges being par allel with the axis. The boards are car ried past the revolving cutters, between rotating pressure rollers, or as they are termed " feed rollers." There are other
revolving cutters, somewhat resembling thick circular saws, arranged so as to cut rebates in the edges of the boards, and form a tongue on one edge, and a groove in the other, at the same time as the face is being planed. These cutters are how ever used for the same purpose in other machines, in combination with different planing cutters. This machine is the in vention of William an Ame rican, and it was patented in this country in 1828. The patent was extended at its expiration, for an additional term of four teen years, and it is said to have yielded a profit to the assignees, who now hold it, of three hundred thousand dollars a year, for the last four or five years. Some idea of its value may be farmed from the above statement, which is made on good authority. It is intended at the next ses sion of Congress to apply for a further extension of the Patent, which expires in 1856 ; but it will be strongly opposed, as an usurpation of public right without a precedent. There are various other ma chines differing but slightly from it, and almost as good.
The planing machine for metal, consists of an iron bed, to which the pieces to be planed are secured by clamps or dogs, Aud which receives a reciprocating motion under the planing tool, which is secured in an adjustable rest attached to a station ary head. The tool is and as the work moves under it, it planes off a nar row shaving, and then requires moving transversely to the direction of the move ment of the work, to plane another sha ving. A surface is thus planed in a series of narrow strips. The operation is some what slow, but very perfect, and is adapt , able to cast or wrought iron, and even to steel. This machine is one of the most useful employed in engineering and ma chine making establishments.