. Appleton's dictionary of machines, mechanics, engine-work, and engineering. ill remainpretty straight and rigid; but the whole of the shrinking will take place on g h, the width, which isslender, flexible, and disposed to become curved from any unequal exposure to the air; the fourmarginal lines of abed, are not likely to alter materially in respect to each other, but they willremain tolerably parallel and square, if originally so formed. A dovetailed box consists of six such pieces, the four sides of which, AB CD, Fig. 3944, are inter-laced at the angles by the dovetails, so that the flexib
. Appleton's dictionary of machines, mechanics, engine-work, and engineering. ill remainpretty straight and rigid; but the whole of the shrinking will take place on g h, the width, which isslender, flexible, and disposed to become curved from any unequal exposure to the air; the fourmarginal lines of abed, are not likely to alter materially in respect to each other, but they willremain tolerably parallel and square, if originally so formed. A dovetailed box consists of six such pieces, the four sides of which, AB CD, Fig. 3944, are inter-laced at the angles by the dovetails, so that the flexible lines, as g h, on B, are connected with, andstrengthened by, the strong lines, as c d, on A, and so on: the whole collectively form a very rigidframe, the more especially when the bottom piece is fixed to the sides by glue or screws, as it entirelyremoves from them the small power of racking upon the four angles, (by a motion like that of the iointed parallel rule,) which might happen if the dovetails, shown on a larger scale in Fig. 3945, wereoosely fitted. 3945. r^ Tt D e When the grain of the four sides A B 0 D runs in the same direction, or parallel with the edges oithe box or drawer, as shown by the shade lines on A and B, and the pieces are equally wet or dry,they will contract or expand equally, and without any mischief or derangement happening to the work ;to insure this condition, the four sides are usually cut out of the same plank. But if the pieces had thegrain in different directions, as C and D, and the two were nailed together, D would entirely preventthe contraction or expansion of C, and the latter would probably be split or cast, from being admissible, it is therefore usual to avoid fixing together those pieces, in which the grain runsrespectively lengthways and crossways, especially where apprehension exists of the occurrence otswelling or shrinking. A wide board, Fig. 3945$, composed of the slips ABODE, (reversed as in Fig. 3942,) i
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Keywords: ., bookcentury1800, booksubjectmechanicalengineering, bookyear1861
