The Technique of FURNITURE MAKING

Perspex

Perspex or acrylic sheet (polymethyl methacry­late) is readily obtainable in clear transparent, pastel shades, full colours, and transfusing and fluorescent colours in thicknesses from V25 in (1 mm) to V2 in (12.5 mm) in colours, and up to 2 in (50 mm) in the clear sheet. It is also supplied in clear rod and tube up to 1 in (25 mm) diameter. Although not as hard as fused glass it has the same clarity and appearance and can be cut very easily with circular saw, band-saw or very fine-toothed handsaw, using low speed and light pressure and feed. It is easily drilled with the normal twist-drill lubricated with a trace of thin oil, and can be bent to simple curves at a temperature just short of boiling water (201° F; 94° C). For accurate bending a wood form should be used, the perspex sheet heated in front of an electric plate or similar source of heat, bent over the form, covered with a cloth and held in position for from one to two minutes to cool and set. Cut edges can be bonded together with simple heat, chloroform or ether, or special perspex cement, and frameless show­cases are now made almost exclusively by this method, with the meeting edges either butted and polished (wet and dry paper, burnishing pastes, etc.) or mitred together, both methods giving invisible joints if well done. There is a growing tendency also to design carcass furniture in flat sheets and simple chair forms in moulded resin, for it is an excellent structural material with outstanding qualities of clarity, strength, rigidity, stability and durability under quite severe conditions of wear, as witness its use in aircraft-work. It is, however, relatively expensive, although no doubt constant research and development, as with all other plastics, will eventually cheapen costs.

28 Drawer unit with sliders in medium impact polystyrene. (By courtesy of Prestige Caterers)

Nylon

Nylon (polyamide) has universal uses as a fibre material for it can be cold drawn to five times its original strength, thus straightening the chain molecules and imparting great strength and excellent wear resistance. It is also invaluable as a sheet material and for castings, mouldings and extruded sections for it is tough, resilient and provides noiseless and frictionless surfaces invaluable for furniture guides, sliders, rollers, etc. It is also used in knock-down fittings, while barbed or serrated nylon dowel-pegs can be glued into such loose-textured materials as chipboard to provide secure anchorages for screws. As it is a thermoplastic without the hard brittleness of the thermosetting resins it can be cut, shaped and drilled with normal hand-tools.

For particulars, manipulating data and sources of supply of other plastics readers are referred to the manufacturers concerned, lists of whom can be obtained from the various periodic journals devoted to the subject and to the standard textbooks available at most libraries.