There is a simple miter clamp commercially available that g excellent results when it is possible to bore half holes in the back of the mi Other satisfactory homemade jigs will be explained later under picture fr; construction in Chapter 2. In general, joints in hardwood should remain clamped 2 or 3 hours longer t those in softwood. The minimum drying time depends upon the room temperal and the type of glue, with the casein and plastic glues setting in from 4 to 7 ho A full 12 hours of setting will insure a sound fit. At least 24 hours should be lowed for seasoning. Finally, it must be realized that although glue will fill gaps it cannot be re upon to tighten loosefitting joints, because it cracks when hardened in the Because of the shrinking and expanding effects of temperature on wood, pai should never be glued in their grooves, nor should the shoulders of tenons touched with the glue brush. Successful gluing operations are insured when clamps are opened to their approximate size before the even film of glue is app to both members of the joint. Waxed paper used freely under the jaws of clai will prevent sticking as the glue dries. 40 . copying patterns SQitaras Working drawings show the shape of curved or scrolled parts by graphing out that portion of the design into equal squares, as shown in Figure 1.39. Since the legend indicates that each square measures 1 in. on a side, a fullsized pattern can be laid out in squares of the indicated size. The points where the lines of the pattern cross the horizontal and vertical lines of the graph or squares are spotted on the drawing and transferred to the fullsized pattern. By connecting these spots the design is reproduced. When only half a pattern is graphed out into squares, the opposite, identical portion can be reproduced by folding the pattern over. To enlarge the drawing, or distort it into a different proportion of length to breadth, it is only necessary to extend the baseline and one side to the required distance and mark off a graph whose spacings total those in the original drawing. The reverse is, of course, true when a drawing is to be reduced in size. r \ 1 \ \ \ \ 1 \ • Fig. 1.39. Enlarging by squares. Fig. i40. Enlarging? a complicated pattern by use of a CABINETMAKING Where the detail of a drawing is rather complicated, the diagonal method often be found to be a speedier means for accurate copying. This is because diagonal lines are added to the horizontal and vertical lines to intersect a gre number of curved and irregular lines in the original matter, as shown in Fi 1.40. Although these diagonals can be added to the simple graph squares, it prove more desirable to outline the original design with a squarecornered "fra whose sides measure in units easy to multiply or divide.