The Technique of FURNITURE MAKING

GLUING THE GROUNDWORK/ SUBSTRATE

Hide glue, shoemakers' paste, dextrin, casein and Cascamite One Shot glue can be used for laying leather, leathercloths and baizes, while wood glue is useful for edges. Animal and paste glues call for very quick working, while if the surface is a large one it may be necessary to glue and lay half the sheet at a time. If the ground-

work is aborbent it should be sized with weak hide glue, while casein and resin glues should be fairly thin and allowed to air dry until they have begun to tack before laying. Particular care must be taken to dust the work thoroughly with a stiff brush before spreading the glue which must be free from lumps or gritty particles, and to work the glue well into the shoulders of the inset. If air bubbles cannot be smoothed out before the glue finally tacks off, prick the bubbles with a needle and cover with a padded weight. Where the leather has to be worked over and round the edges (306:2) glue and lay up to the edges, glue the edges and coax the leather over, stretching it gently and evenly and temporarily securing it with fine pins. Rounded edges tend to puff or belly out, and the edges should be repeatedly smoothed over with the thumb. A flexible leather will probably flow over well-rounded corners, but sharp edges are always difficult and the leather will have to be cut. Figure 306:3 shows the most satisfactory method with the cut at an angle and not on the edge of the corner; while 306:4 illustrates a neat method of finishing off underneath, using a hardwood strip which is glued in after the leather has been fixed and allowed to dry. Leather can be worked round acute bends if it is first dampened, but the grain texture is lost and the colour may be affected, therefore it should be avoided if possible.

PVC leathercloths are laid in exactly the same way, but they must be cut to size if method (b) above is adopted as there is not the same measure of elasticity, while rounded corners will have to be tailored. Baize is also laid in similar fashion but certain precautions must be taken: there must be no surplus glue and pressure must be very gentle or the glue will soak through, leaving hard white patches which cannot be eradicated. Cheap quality cloths may also shrink back considerably as they dry, and a preliminary test should be made to determine the extent, if any, of the shrinkage.