GB1421602A - Hull for sailing boats - Google Patents

Abstract

1421602 Plastic boats H STOBERL 12 Jan 1973 [12 Jan 1972] 1785/73 Heading B7A [Also in Divisions B4-B5] A hull for a sailing boat made of fibre-reinforced plastics having a double-skin shell and deck with rigid foam filling between the skins, is produced by applying at least one layer of synthetic plastics to each of two complementary mould parts, allowing the layers to harden at least partially and applying a further layer thereover, applying a fibrous multi-layer inlay thereto and subjecting the inlay to a vacuum to press the inlay into and partially embed it in the further layer, bringing the mould parts together to close the mould and filling the cavity between the two mouldings with a foamed material which penetrates the inlay up to the further layer, driving air out of the mould cavity through a vent in one or both mould parts. As shown in Fig. la, the hull 100 consists of a shell 101 having an inner bottom skin 106, a bow 104 and stern 103 and a doubleskin deck portion 102. The inner bottom 106 has a central supporting portion 129, Fig. la. Foam material 9 is charged between the skins and bonded thereto on all sides, the construction also including reinforcing laminations, e.g. 141, 141a. The hull also has a recess 132 to receive a keel 105, a spinnaker funnel 107 and guide 109, forestay sail 142 and guide 108, mast aperture 111 and foot 139, cockpit aperture 118, and bushed rudder post tube 122. In moulding the shell portion, the outer mould half 10, Fig. 2a is coated with resin 5 and fibrous layer 1 and vacuum bag 8 applied thereto, vacuum being drawn through connection 18. Bag 8 has a sealing rib 8a located in groove 16 in mould half 10 and held by vacuum drawn through passage 12. Passages 13-15 allow venting of air. Upper mould half 11 having similarly prepared multilayers 1, 5 thereon is then placed on half 10, the ends being joined by shell connector 25, and the cavity between the shells filled with foam material through tube 20. The layer 1 may comprise a strength layer (2, Figs. 7, not shown) e.g. of glass fibre, an intermediate fleece layer (3) and a coarse thread layer (4) e.g. of coarse, curled fibres. Thick threads of the coarse layer may be needled through outer layers to form loops (3a, 4a) to improve bonding. The mould parts, Fig. 5f, may comprise inner and outer shells 10b, 10c, 11b, 11c, containing support inserts 10d, 11d, e.g. end-grained wood blocks, foam material blocks, honeycomb structures &c. located to withstand radial forces.