The Technique of FURNITURE MAKING
Heat-resistant qualities
Standard quality laminates are resistant against the surface temperature not exceeding 302° F (150° C) but will not resist intense localized heat, such as neglected cigarette butts, etc. Incorporating a metal foil in the laminate will tend to spread such localized heat over a wider area, and a cigarette-proof grade is available which gives reasonable protection. Such heat - resistant grades are not suitable for continuously damp situations (kitchen-sink fixtures, etc.), and will not bend so readily as the standard grades.
Real wood laminates
Plastic laminates in which the top sheet is true wood veneer instead of printed paper are available (Belfort, etc.). The sheets have the authentic depth, warmth and natural beauty of wood, although the grain is filled with resin and the natural texture is lost. In all other respects, methods of manufacture, toughness, durability, resistance to heat, moisture, acids, stains, etc., and cutting and gluing/bonding procedures are identical, while the cost compares favourably with that of other laminates.
LEATHERS
Natural cowhides, specially dressed, and softened by a crimping action which pushes the fibres over each other so that they can slide easily giving the requisite suppleness, are extensively used in upholstery, and are commonly known as furniture-hides. They are slit from the tanned hides to a usual thickness of about 1/16 in (1.5 mm). pigmented or dyed, and dressed with a spray coat of synthetic lacquer.
Second quality hides are often grained between rollers. The grains can be heavy, medium or light textured, and are done either to accentuate the natural grain texture, or to even out the applied colour and to mask the inevitable defects which occur in every hide, i. e. barbed-wire weals and punctures of the 'prick' or warble fly which, it is estimated, cost the tanning industry millions each year in spoilt hides. The coloration can be an opaque dressing, sealed with a little gum arabic, or straight aniline dyes which penetrate the hide and yield a clearer finish than the heavy
30 Cowhide measurements
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pigments which lie on the surface and tend to show as white cracks if the hide is heavily pulled or dressed. The advantage of leather, apart from its intrinsic beauty, is its tolerance of wetting, pulling and stretching over acute compound shapes, while it has a natural resilience which will accommodate considerable deflection. A typical cowhide will contain from 50 to 60 sq. ft (4.645 to 5.574 m2) measured out to all edges, and Figure 30 shows the dimensions to be expected from an average hide (the standard allowance for waste in cutting to final dimensions should not be less than 60 per cent). Goat-skins—Cape Levant, Morocco, Niger, etc.—are much smaller and more expensive, and usually reserved for table linings, small seatings, etc. They are either aniline or vegetable dyed, and native skins are invariably untextured. Skivers (sheep-skin), calf-skin, etc. are rarely used in furniture as they are more delicate and wear too easily. Shagreen (shark's skin) is only used in small panels for ornamental boxes, etc.; and occasionally other exotic leathers are used as fashion dictates, but cowhide and goat-skins are the mainstays, with plastic-coated cloths (leathercloths) a fair substitute. A description of table-lining methods is given in Chapter 33.
PLASTIC COVERINGS, LEATHER - CLOTHS, ETC.
Besides the innumerable transparent or patterned sheet materials, polyvinyl acetate resins (PVC) are coated on a variety of base materials, wool (Yana), cotton twill and jersey fabric (Lionide, Ambla, Flexknit, etc.), to yield light-, medium - and heavyweight cloths which have all the advantages of true plastics, i. e. long flex life without ageing, resistance to spilt acids, stains and greases, water resistance, etc. Some are produced as impregnated woven fabrics for upholstery, etc.. similar in all respects to natural woven materials, while others are close coated and grained in so exact a simulation of natural leather that it is sometimes difficult to tell the difference unless the edges are examined. These have a rapidly expanding use in wall coverings, spring and foam-covered seating, etc., with the added advantages of cheapness and continuous widths free from all defects, although they lack the beauty of the natural material, and have not the same recovery value under seating pressure as good leather.
