TECHNICAL CATALOGUE ICR PRODUCTS IN THE GRP BOATS PRODUCTION PROCESS Plugs
Usually, the framework of the plug is assembled and thewooden panels fixed to the garboards with thixotropic glue with a high bonding power and low shrinkage.The shaped wooden panels are coated with stopper that canbe easily applied by boat knife. It can also be easily sanded and worked within a reasonable time.When the marine putty has fully polymerized, the articles are sandedwith abrasives. At the end of the process, the surface of themodel will be even and very hard, ready to be coated withsprayed finishing stopper: this product must be quick to apply, easily sanded and polished in order to be the ideal base forthe construction of the mould. To get an even better surface quality, putty can be overcoated with a glossy top coat. Assembly
All the GRP laminates of a boat are assembled together with very hard, low shrinkage thixotropic glues.The hull and deck are always fixed together with bolts andrivets. To ensure the watertight, hull and deck are sealed outside with structural adhesives or long open time glue and have to be banded with fabrics outside.The bulkheads, which are normally built of marine plywood(small boats) and with sandwich panels for medium-large craft, are positioned with glue. After this, the bulkheads are laminated along their entire perimeter with resin-impregnated fabric. Lamination Bodywork
After the gelcoat has been applied, the next phase in theproduction of a GRP laminate is the stratification with matand fabrics of different characteristics and weight. Theselayers are impregnated with resin until the required thickness has been obtained.Some of the linking radius are undersized in many articles:owing to lack of space, the operator will be unable to position the first mat in direct contact with the gelcoat. Special, very hard, easily workable glues that do not shrink are used to get over this processing error, which often gives rise to bubbles and defects requiring great labour to eliminate them. To reduce the weight of the articles while maintaining excellent mechanical characteristics, sheets of light and resistant core materials (such as PVC, balsa, termanto) are glued to the external skin. Specific bonders withhigh adhesive power and low weight density (from 0.7 to 1.3kg per liter) are used to fix these.The laminate is completed by stratifying the “internal skin”which will be subsequently reinforced with floor plates and longitudinal members: these medium-density polyurethane structures can be positioned with glue and then laminated with resin-impregnated fabrics. For the joining of the laminates, hard and thixotropic glues are applied for filling the space; to form a continuous and uniform surface, low shrinkage putties are then applied before the touching up with gelcoat. . 4