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Flooring Cramp

lever, joist, board and piece

FLOORING CRAMP. A machine invented by Mr. Andrew Smith, for laying down floors, so as to make very tight and close joints with great facility. The annexed engraving shows a perspective view of the machine as in opera tion, by which its construction and the mode of using it are both made apparent. a is a lever of the second class, about 2 feet 6 inches long, with a handle at the upper end, and forked at the lower so as to be attached to two of the opposite sides of a block of cast iron b, by bolts at e. The block b is about 6 inches square, and 3 deep, with a large groove capable of being increased or diminished in its depth for the reception of joists of different sizes. For this purpose, it has on one side a shifting loose cleat or plate e, kept in its place by stout pins; and on the other end, on the other side of the joist, there is another groove d, which contains two pieces of metal, with wedge-formed surfaces; between thew the long driving wedge f is forced by a alight blow with a ham mer, which compresses the joist between the metallic surfaces, which are jagged or armed with short projecting teeth, that fix themselves into the wood, and gripe it very fast; g is a movable piece of cast iron, made to press against the edge of the flooring board, with its broadest side ; the two other sides or parts of this piece are stout square bars, at right angles with the other, which are inserted a part of their breadth in shallow grooves, one on each side of the block b, and serve to guide the former in its action. It will be observed that the

two forks of the lever a pass through the side bars of p, which therefore gives it motion. To use this machine, it is put upon the joist, and pushed up to the board laid down ; a slight blow upon the wedge / fixes it firmly to its place; the handle of the lever is then pulled workman towards the boards causing the sliding piece g to press the of the boards together with as much force as to render their junction imperceptible; the stay k is jointed loosely to the back of the lever a, and following the motion of the lever, the jagged end of its lower extremity sticks into the joist, holds the lever in the position it was drawn, and preserves the pressure against the board, while it is nailed down by the workman. To remove the cramp, all that is necessary is to strike the wedge on the opposite side, which loosens the whole, when it is ' drawn back to take the next board, which is operated upon in a similar manner.