Patent GB-763251-A (GB)
Title: Improved and simplified method of reinforced laminated fibre construction
Filed: 1953-11-12
Abstract: Articles are made from, or repaired or sheathed with, reinforced synthetic resin by a process in which: (i) fibrous reinforcement and a supporting structure therefor are given the required shape, the supporting structure being deformable but stiffer than the reinforcement, (ii) the fibrous reinforcement is impregnated or coated with synthetic resin before, during or after the shaping, (iii) at least part of the setting of the synthetic resin is effected without the use of a mould.  The supporting structure may either carry the fibrous reinforcement or be interspersed with it.  In one form the supporting structure is a metal network or grid, or perforated or unperforated foil, and is preformed by hand or in a press.  In another form the supporting structure is of metal filaments which are wound on a suitable forme.  The supporting structure may be of synthetic resin, previously moulded.  Fibrous reinforcing material, felted or woven, may be attached to the supporting structure by adhesive, sewing or clips, or chopped fibres may be blown on, and synthetic resin sprayed on the supporting structure.  The support, instead of being preformed, may take the form of wire or synthetic resin filament woven with the reinforcing material, the support and the reinforcement being shaped together. The synthetic resin, which may be of the cold setting type, may be applied by spraying, brushing, pouring or dipping.  Thermosetting resins which require heating to cure them are preferably heated by infra red radiation, which is especially suitable when the supporting structure is metallic.  The curing time may be reduced by mixing metal powder in the resin.  Alternatively an electric current may be passed through a metal supporting structure, or high frequency induction heating may be used.  The invention may be applied to the repair of a hole, e.g. in the hull of a yacht, using wire netting as the supporting structure, secured over the hole and shaped to the contour of the hull.  Layers of cold-setting resin-impregnated fibrous cloth are wired to the wire netting and another wire netting support placed on the other side, the outside covered with woven glass fibre cloth and low pressure applied to each side of the patch by inflated rubber cushions.  When used for sheathing or coating, e.g. of the bottom of the hull of a dinghy, wire is threaded through the mesh of pieces of woven glass fibre which is then laid on the hull and a cold setting resin applied by brushing.  Alternatively the resin may be partially cured and the cloth pressed before application.  In a typical process for making an article, e.g. a wash basin, wire netting is shaped on the surface of a dismountable wooden former, removed, felted glass fibre cloth soaked in cold setting resin applied to the surface of the former, the wire netting structure placed on the cloth and covered by a second layer of resin-soaked cloth, after which the layers are consolidated by light rolling and the resin left to set.  Articles such as bowls are also made by pressure between dies, the supporting structure being filaments of synthetic resin threaded through the fibrous reinforcing cloth.  For motor-car bodies wire is woven with asbestos cloth, the sheets shaped in a press, sprayed with thermosetting resin, pressed again to consolidate the resin and subjected to heat, e.g. in a heated chamber.  Alternatively the resin in the impregnated sheets may be partially set before pressing.  Ship hulls may be constructed from cloth woven from steel wire and asbestos fibres, in several layers, using a set of female moulds supported on a temporary wooden structure.  Bulkheads and decks are prefabricated from sheets of combined reinforcing and supporting material cut to shape and impregnated with synthetic resin, the requisite number of layers being used for the thickness required.  Structural members may be formed by bending lengths of material made according to the invention when partly set.  Other articles mentioned in the first Provisional Specification are trunks, troughs, pipes and shelves.